Sunday, May 31, 2009

Summer Research - Drafted May 31st

Tomorrow I start my summer rotation in the Neuroscience program at the University of Iowa. I am working with Dr. Jean Gordon on two projects, one entitled "Phonological neighborhoods in aphasia" and the other entitled, "The Relationship between Language Use and the Perception of Wisdom." I am very excited to begin working on these research projects. A few thoughts before I begin this work. I can't believe that I have come this far. It is something special to accomplish a goal that you have worked a majority of your life for. However, I am not satisfied just making it here. I need to continue to learn and accomplish and set higher goals. This is a chance to challenge myself and to go for bigger and better things ahead. I feel as though I have entered the field at one of the most exciting times. I think that we are on the brink of some major discoveries and about to open the door to hundreds of new questions. The advances in technology and our increasing abilities to attack the questions of the mind are placing us at an interesting time.

One problem with the speed of our discoveries and our advancements is our ability to recognize the impact and the consequences of our actions. There are many ethical questions to deal with when we confront these new discoveries. How are we supposed to understand and handle these things which are so new to us and deal with the most personal aspects of ourselves? In understanding the mind and how it works, we are understanding ourselves. Do we truly want to know everything about ourselves? Or maybe more appropriately, do we want others to know everything about us? Issues with genetics, how we think and why we think will make our personal lives very public.

This is where the topics of one of the research projects applies. We need to look to the wisdom of those who have come before us in applying and using our new discoveries. Although the frontiers that we are entering are unlike any that we have approached before, we must tread carefully in these times. I too will look to the mistakes of those who have come before me and seek counsel from those who have experienced all that I am about to. I look to the experience with excitement and nerves but know that while it may be hard at times, that it is one of the most exciting experiences I will have.

Thursday, May 28, 2009

Memory

Tomorrow I start the real journey. I will arrive in Iowa in the afternoon, unpack and begin to figure my way around a new city and a new life. I am excited for the opportunity to follow my dreams. However, because of this excitement and moving, I will be lazy and post a sweet paper on memory that I wrote earlier this year.

Does Long Term Potentiation (LTP) Equal Learning/Memory?
Learning is considered the acquisition and development of memories and modification or acquisition of behaviors (Sweatt, 2003). It is the product of experience and ranges from simple forms of learning such as habituation to more complex forms such as play. Learning does not stand alone as having its own mechanism, but instead works within the context of both memory and recall. Memory is the process through which learned information is stored while recall is the conscious or unconscious retrieval process through which this altered behavior is manifest (Sweatt, 2003). Current understanding of neurons and the central nervous system implies that the processes of learning and memory correspond to changes in the relationship between certain neurons in the brain (Martin, Grimwood, & Morris, 2000). This can be defined as synaptic plasticity. As certain neurons are used while learning a behavior, the experience and repetitive use of the neurons will lead to the strengthening or weakening of the connections between them and finally the establishment of the learned behavior. However, does the change in neuronal strength or structure actually equal memory? Could there be other mechanisms that are used in the acquisition of altered behavioral responses?
Long-term potentiation (LTP) is the most studied form of synaptic plasticity in the central nervous system (McEachern and Shaw, 1996). LTP has received extensive attention because it shares a number of characteristics with memory, in that they both have a rapid onset and long duration and are strengthened by repetition. In addition, the duration of LTP being correlated with the time course of forgetting (Diamond, Dunwiddie, & Rose, 1988). However, in the thirty years since the discovery of LTP, the mechanisms have not been resolved. Instead, only many intricacies have been uncovered. Although many mechanisms of LTP have been shown to be involved in different learning and memory paradigms, does LTP equal memory and learning? Investigating these questions requires an explanation of learning, LTP, models of learning outside of LTP and finally a discussion of techniques in future research that should be used to investigated whether LTP is the mechanism for learning.
Learning
Learning, the altered behavioral response due to an environmental stimulus is thought to be stored in the cortex for both explicit (declarative) and implicit (procedural) learning (Sweatt, 2003). There are many forms of learning, from more simple forms of learning including habituation to more complex forms of learning, including associative conditioning. These two forms of learning are some of the most studied and best understood. Habituation is the cessation of a response to a stimulus after repeated presentations of the stimulus (Sweatt, 2003). One example of habituation that is well studied is in the Aplysia. The gill of the Aplysia must be thin and have a large surface area because it is where oxygen exchange occurs and this makes it susceptible to damage, so the animal presents many reflexes in order to protect it (Byrne & Kandel, 1996). Typically a touch applied to the siphon every 3 minutes over a period over 4 hours will result in a gradual cessation of the withdrawal response; a phenomenon called habituation (Byrne & Kandel, 1996). Experimenters showed that depression of the synapse between the sensory and motor neurons was the main underlying cause of habituation. Additional experiments showed that this synaptic depression is caused by a reduction in the amount of neurotransmitter released from the presynaptic sensory neurons (Cohen, Kaplan, Kandel, & Hawkins, 1997). There is inactivation of post-synaptic calcium channels and there is a reduction in the number of presynaptic vesicles that are available to release neurotransmitter. The reduction of the calcium channels is regulated by secondary messenger cascades which causes the down-regulation in the expression of the calcium channels. Two other forms of learning associated with habituation were demonstrated in the Aplysia, including dishabituation and sensitization (Cohen et al., 1997). Dishabituation is the full recovery of the original strength of a habituated response after the presentation of a strong, novel stimulus (Sweatt, 2003). Sensitization is the increase in strength of any reflex to a level above its original strength that is caused by one or more strong stimuli other than the stimulus that usually evokes the stimulus. After an Aplysia has been habituated, if the animal receives a strong touch to the tail, the next touch on the siphon will cause the gill to withdraw. Aplysia can be sensitized to a strong touch to the tail. A tap to the siphon, lighter than that used to habituate the animal, will cause the gill to be strongly withdrawn (Cohen et al., 1997).
In associative conditioning, an animal forms an association between two different stimuli (Dayan et al., 2000). One stimulus, the unconditioned stimulus (UCS), normally evokes a reflex. The other stimulus, the conditioned stimulus (CS) usually evokes no response (Dayan et al., 2000). When the conditioned stimulus is presented shortly before the unconditioned stimulus in a series of trials, the animal eventually responds to the conditioned stimulus alone. After conditioning, the animal forms an association between the conditioned stimulus and the unconditioned stimulus. There are two competing theories about how this form of learning works. In stimulus-response theory, the organism learns to form an association between the CS and the UCS. In the opposing theory, called the stimulus-stimulus theory, it is suggested that a cognitive component is required to understand classical conditioning (Rescorla and Wagner, 1972). In relation to the Aplysia, the presentation of the CS, such as the shock would elicit the siphon withdrawal reaction, whereas in the stimulus-stimulus theory the Aplysia would withdraw its gill because the UCS is associated with the concept of the shock. It is through an understanding of the different types of memory, that one is able to understand the biological underpinnings of these mechanisms. Form is often related to function, by knowing what the form looks or acts like (the behavior of memory) we can investigate its functions (the biological processes) which build the form.
Long-Term Potentiation
Several areas of the brain play a part in the consolidation of memories, but the hippocampus has been recognized as playing a vital role. Many of the following experiments involved an exploration of how synaptic plasticity functions in the hippocampus. One of the least understood, but most interesting problems in neuroscience is the attempt to identify the mechanisms which underlie memory. In 1949, Hebb proposed a well-defined rule of synaptic plasticity. He proposed that coincident activity in two connected neurons leads to strengthening of their connection (Chen & Tonegawa, 1997). This specifically increases the probability that they will fire together in the future. Through experimentation, it has been found that activity-dependent synaptic plasticity plays a vital role in sculpting synaptic connections during development (Lynch, 2000). LTP was first identified by Lomo, who reported that a single, short test shock , following an initial period of conditioning test shocks to the perforant path, elicited a potentiated response in the dentate gyrus (Lynch, 2000). After a train of stimuli, an elevated response of EPSPs (as measured by the membrane potential) in the postsynaptic cell (dentate gyrus) were noted. Later, Bliss and Lomo reported in 1973 that trains of high-frequency stimulation to the rabbit perforant path caused a sustained increase in efficiency of synaptic transmission in the granule cells of the dentate gyrus (Lynch, 2000). Chemical synapses are not static. Postsynaptic potentials (PSPs) wax and wane, depending on the recent and long-term history of presynaptic activity. In some synapses PSPs increase during repetitive stimulation to many times the size of an isolated PSP. A gradual rise of PSP amplitude during stimulation is called potentiation (Zucker, 1989). It is these changes in the frequency of firing and the amount of firing that synapses receive or do not receive that causes the changes in synaptic arboration. Subsequentl, it is the changes in the arboration and the interconnections of the synapses which are hypothesized to represent memory. These discoveries have lead to the formation of the synaptic plasticity model (SPM) of learning and memory (Martin, Grimwood, & Morris, 2000). The formal hypothesis of the SPM states that “activity dependent synaptic plasticity is induced at appropriate synapses during memory formation, and is both necessary and sufficient for information storage underlying the type of memory mediated by the brain area in which that plasticity is observed” (Martin, Grimwood, & Morris, 2000, 650). A thorough evaluation of the SPM hypothesis requires experimentation that addresses both the necessity and sufficiency. However, the current shortfall in the model, lies in the lack of experimentation in establishing the sufficiency of synaptic plasticity to induce memory (Martin, Grimwood, & Morris, 2000).
As demonstrated by the experiments in relating LTP in the hippocampus, a majority of the work on the cellular basis for memory has focused almost exclusively on hippocampal LTP/LTD and the belief that these forms of synaptic plasticity are a substrate for memory (Stevens, 1998). However, LTP has been observed in other brain areas, for example, the amygdala. Fear conditioning has been demonstrated to elicit LTP in the amygdala. Most of the evidence on the issue boils down to the observation that blocking LTP/LTD also interferes with the learning of spatial tasks (Stevens, 1998). Before settling upon an answer to whether LTP is the mechanism of memory in the hippocampus or other brain areas, the understanding of LTP itself, needs to be addressed. As LTP is further investigated, more intricacies are discovered, so to be able to conclude the role of LTP in memory, the meaning/definition of LTP needs to be lain out. However, we may be able to conclude that LTP, as currently defined and understood, is a mechanism that is concurrent with memory and memory associated areas.
Other Experimental Models of Learning in Synaptic Changes
Although LTP has established itself as the leading model learning and memory, there are other models that may explain these phenomena, including kindling (McEachern and Shaw, 1996). In kindling, daily trains of sub-convulsive electrical stimuli delivered to brain cortical or limbic sites eventually culminate in behavioral and electrographic seizure expression. A short burst of action potentials (afterdischarge; AD) follows each stimulus, and with additional stimulations, there is a progression of both electrical and behavioral measures of seizure activity. As AD duration increases, the AD localization spreads from the original focus of activation to downstream synaptic connections (McEachern and Shaw, 1996). The kindling phenomenon is associated with long-lasting facilitation of synaptic transmission. With the spread of activation and the facilitation of transmission, the kindling effect leads to increased proliferation (neurogenesis) of neurons. This model of synaptic plasticity is now best known as the model for epilepsy, but it was also one of the first neuroplasticity phenomenon suggested in learning. While it may appear odd that the abnormal firing behavior of seizures could be similar to learning, it may be that they share similar mechanisms or cascades, just with different outcomes (McEachern & Shaw, 1996).
While kindling may not be a close representative of normal neural firing and activity, other models are more subtle in their attempt to explain plastic changes in the brain, including primed burst potentiation (PBP) and spike-timing dependent plasticity (STDP). Two prominent physiological features of the hippocampus, complex spike discharge and theta rhythm are effective in potentiating synapses (Diamond, Dunwiddie, & Rose, 1988). PBP and LTP have common mechanisms in that both are not additive when both paradigms are used to stimulate a synapse and both are blocked with NMDA antagonists (Diamond, Dunwiddie, & Rose, 1988). PBP consists of a pattern of stimulation, a single priming pulse followed by a high frequency burst of pulses (Diamond, Dunwiddie, & Rose, 1988). Since the mechanisms of PBP are endogenous to the hippocampus during learning, it may activate the mechanisms of memory formation. One aspect of PBP which is very important is the dependence on the temporal components of stimulation, and this effect may be relevant to hippocampal-dependent learning, as a model of associative memory. PBP and its temporal nature are similar in aspect to STDP.
STDP exemplifies the importance of the temporal order of pre/post spiking for synaptic modification in the nervous system (Mu, & Poo, 2006). The synaptic strength can thus be bidirectionally modified by correlated pre/post spiking within a narrow time window, with pre-post spiking leading to LTP like modifications and post-pre spiking leading to LTD like modifications (Mu, & Poo, 2006). However, these temporal windows can change in both the time frame that the spiking has to occur within, and also which modifications occur according to the inputs. With the LTP and LTD consequences associated with the STDP, it may be assumed that STDP is simply these two phenomena on the level of individual neurons, however, STDP may serve to be a more parsimonious explanation as the mechanism for memory. The temporal nature of STDP allows for associations to be established. By pairing the modulation of STDP by inhibitory inputs and complex spike trains, STDP appears to use more complex mechanisms to store the differences in cell communication and thus more accurately represent the messages of the cells.
Examples that Challenge the Definition of Learning
While research often has a very anthropomorphic centered idealism, especially concerning research in the brain, it is ironic that much of what is known about the nervous system and the mechanisms of the brain comes from research with invertebrates. As discussed earlier, much of the initial work with LTP was demonstrated in the Aplysia, however, experiments with LTP use many different animal models today. Higher cognitive processes such as more complex forms of learning are thought to be demonstrated in “higher” species. This bias flows throughout the biological kingdom in varying degrees, and is applied to different organisms. Many have thought that it takes a nervous system to be able to learn. However, if the strictest definitions of learning are used, learning has been demonstrated in two species that many would have denied the ability to learn, the paramecium and the venus flytrap.
Learning in the Paramecium
While certain forms of learning are thought to be processes that requires large neuronal development and higher areas of brain functioning, it can also be seen in the single-celled organism, the paramecium. The paramecium does not have any neurons, so the question becomes, how can it learn? The question of whether paramecia exhibit learning has been the object of many experiments which yielded few answers to it. In a recent experiment by Armus et al. (2006), discrimination learning was demonstrated in the paramecium. Prior investigations into the possibility of classical conditioning in paramecium have shown different results. French (1940) reported that the time it took a paramecium to escape a tube decreased with the number of trials and this result was later confirmed by Huber et al. (1974) cited in Armus et al., 2006. Another approach attempted to condition paramecium to stimuli such as brightness or vibration to electric shock or heat. This included experiments, included in a review by Armus (2006) by Bramstedt (1935) and Soest (1937) who reported successful conditioning, while experiments by Best (1954) and Mirsky and Katz (1958) did not.
In the experiment by Armus et al., 288 paramecia (P. caudatum) were trained in a 22 mm long transparent glass trough which was half light and half dark. There was a stainless steel wire electrode that projected 2mm into the water at each end and the shock was provided by a 6.5 V DC with a duration of 60 ms. The subjects were observed through a microscope under 10X magnification. The paramecium were then collected individually from the colony and subjected to 7 periods of training and 3 periods of test. Three groups of 96 subjects differed in their training procedures, including, the experimental group which received a train of shocks when the paramecium was in the cathode half of the trough, the no shock control, and the paired shock control which received a train of shocks whether it was in the anode or cathode half of the trough (Armus et al., 2006). The paramecium are attracted to electrical shocks so learning would be demonstrated by the paramecium’s ability to discriminate between the side on which it received the shocks and the side in which it did not. The paramecium were supposed to associate the level of brightness of the trough with the shock. The results of the experiment showed that the experimental group spent significantly more time in the portion of the trough which was giving the shocks than the control group. However, there may have been confounding factors in this experiment. The shocks may have changed the liquid itself and made that more attractive to the paramecium. The authors addressed this with a second experiment. The brightness level from the training session was switched for the test session so as to eliminate any possibility that some substance that was hypothetically being produced by the shocks wasn’t the thing attracting the paramecium. The experimental group again spent more time in the shock part of the trough than the control group, demonstrating associative learning by the paramecium (Armus et al., 2006).
The results of this and other associated experiments bring into question our current description and understanding of learning. Is learning at its most basic level the change in behavior in response to time? However, where does the paramecium store its past behaviors, how does it associate the past to the present, is it a simple interaction of the molecules in the paramecium to the environment of the trough or is this organism, learning? This raises important points to consider. Can learning or memory be stored in many different ways? Memory may simply be the correlate of an increase in certain biological substances which in certain concentrations cause different reactions to occur. The paramecium may represent the learning or memory storage of one of our brain cells. A stimulus causes a change in the cells biological chemistry which then causes it to “remember” a situation, which could be viewed as either a positive or negative experience. In the view of a human, with many neurons and neural networks, memory and learning may represent the final outcome of a series of checks and balances representing all of the intricacies of an individual situation or experience through positive and negative gateways. It is interesting to consider the ability of organisms to “remember” and learn when none of the usually proposed manners of memory or learning are present.
Learning in the Venus Flytrap
Using the definition of learning as change in an animal’s behavioral response as a result of a unique environmental stimulus allows various nonassociative forms of learning such as sensitization to be included as learning (Sweatt, 2003). This may raise the question of whether sensitization in the venus flytrap plant is learning. The triggering mechanism for closure of the trap was two lobes with their surfaces facing inward each with three trigger hairs (Sweatt, 2003). To eliminate “false alarms,” the plant has evolved a mechanism whereby stimulation of a single trigger hair is insufficient to cause the trap to close (Sweatt, 2003). Two hairs must be stimulated in succession (or simultaneously) to trigger a trapping response. In one circumstance, stimulating a particular trigger will give no response, whereas stimulating the same trigger in another will, showing an altered response due to particular environmental stimuli (Sweatt, 2003). In a study by Volkov et al. (2008), the kinetics and mechanism of the trap closing were studied. Transmission of a single electric charge (mean 13.63 mC) caused the plant to close. A summation of stimuli is demonstrated through the application of smaller charges, if two or more consecutive charges were applied within a period of less than 50s the trap closed when the total of 14 mC was reached (Volkov, 2008). This cumulative character of the electrical stimuli indicates the existence of electrical memory in the plant. This form of learning may be comparable to PBP or STDP. The small background firing of the cell is interrupted by the sudden firing of one of the trigger hairs and this combination of firing patterns enough times strengthens the connections between the cells. Although the changes may not represent a long lasting change, enough stimulations may lead to a chemical change in the synapse which may make the “memories” longer lasting. This type of memory system may be analogous to planarians memory systems, which appear to be based in chemical changes of the entire organism.
The Future
While much of the work so far has been integral to bringing us to where we are today in our knowledge of memory and learning, there is a lot of work left to do. One of the major obstacles in the future remains identifying and establishing all of the phases of LTP, including the biological functions. However, while it will be interesting to discover all of the components and functions of LTP, is this the mechanism of memory and learning? While it may be integral to memory in the amygdala and the hippocampus, memories, appear to eventually be stored in the cortex. Are memories in the cortex stored by LTP, are they reactivated and reconsolidated through LTP or some other mechanism? While research may be years away from understanding LTP, memory and learning, there are many functions and mechanisms that can be further investigated. Future research should continue the use of genetic manipulation and investigation. By manipulating the expression of genes and other proteins, one by one or in conjunction with a series of other genes or proteins, we can piece together the changing and varying effects have a better understanding of the changes from a biological view-point. The use of a combination of methods will also be very interesting and helpful. Combining, PET, fMRI, genetic manipulation and behavioral paradigms will give researchers information and data from so many different views that they will be able to associate how changes in genes, lead to increases in one part of the brain which cause certain behavioral changes. Researchers should also remember to investigate both cases where there is severely impaired memory, but also where there is superior memory. Cases such as S or other mnemonists should be investigated, looking at genes, their biological makeup and their brain activity during learning and recall. Since memory and learning are so complex, we may never have a full grasp on how it works in all situations, but as technology improves and knowledge increases, memory will be better understood.
Conclusions
While much of the research in memory and learning points to the importance and necessity of LTP for memory and learning, other evidence points to the possibility of other mechanisms. Much of the current research points to the hippocampus as the site of memory consolidation, however, it has also been demonstrated that long-term memories are not stored in the hippocampus. If LTP/LTP were the only mechanism for the storage of memory, then memory and LTP should follow a linear relationship that when plotted against each other, shows memory increasing as LTP increases. However, as Sweatt (2003) demonstrates, there are many studies that show that this is not the case. While LTP may appear to be a very functionally sound mechanism for storing memories and also one that appears to fit with many people’s preconceptions of memory, in some cases it may not serve the best function. If LTP were to be the only mechanism for memory and the locations of memories were pinpointed, they could be easily erased with depotentiation of the synapse. However, while these discussions may last for a long time, it may come down to a person’s definition of the related components of the argument. To decide whether LTP is memory or learning or if LTP is just one of many mechanisms, it will take a better understanding of LTP itself, reconsolidation properties and the mechanisms which store memory in the cortex.

Tuesday, May 26, 2009

Memory

Yesterday's post was permeated with the topic of today, memory. The cases of H.M. and Clive Wearing have contributed much to the study and understanding of memory. Although we are still unsure as to how the memory system exactly works. Through the use of the lesion method and other experiemental methods involving animals and scanning techniques, we have been able to uncover a lot about the memory system. Last year I wrote a case report about Zatsesky (sic), a Russian soldier injured in combat who was the protagonist of the book, The Man with a Shattered World: The History of a Brain Wound., by A.R. Luria. In the book, Zatsesky describes relearning how to do everything and how painstaking it is to recognize that he has lost the ability to remember certain things.

How does memory work? How can we enhance memory? How can we forget unwanted memories?

I will attach a paper on learning and memory and tomorrow...
(dial-up internet and blogs don't work to well together)
I will finish more of this too...

Memory

Yesterday's post was permeated with the topic of today, memory. The cases of H.M. and Clive Wearing have contributed much to the study and understanding of memory. Although we are still unsure as to how the memory system exactly works. Through the use of the lesion method and other experiemental methods involving animals and scanning techniques, we have been able to uncover a lot about the memory system. Last year I wrote a case report about Zats

Monday, May 25, 2009

Lesions

One of the ways that we lose our mental abilities is through the development of brain lesions. Whether from various diseases, traumas, other other sources, they all appear to end the same way, with some sort of disruption of mental facilities. While the lesion can be devastating and disruptive to an individual, it provides the opportunity for researchers to look at the mind that ethics and modern science would otherwise not allow. In experiments, good scientists look to control for every factor that they can. Experimenting with the human mind or brain, there have been temporary ways to knock out part of the brain as in the Wada test or through the use of TMS. However, to permanently remove some part of the brain would be unethical. With lesions of the brain, nature has made these temporary knock-outs permanent and has also made them (generally) very focally. Through the use of brain imaging techniques and behavioral assays, the location of the lesion can generally be identified. When a lesion is identified, testing to see how the loss of a certain part of the brain can begin.

Although some are not exact definitions of the lesion technique, the following names have offered much to the study of the brain through their loss of. Phineas Gage is probably one of the best known examples of the lesion. While working on a railroad in the 19th century, a tamping rod exploded and shot through the skull of Gage. He survived the accident, but his friends would later describe him as, "Gage was no longer Gage." It appears that the part of the brain that was lost in the accident was part of the system for regulating emotions and drive. Another example would include the man H.M. As a boy he suffered intractable seizures from epilepsy. His doctor (Scoville) decided to remove the areas from where the seizures were originating, which happened to be approximately 2/3 of the hippocampus, and surrounding area as well as the amygdala bilaterally. After the surgery it appeared that he had no memory for the present and was unable to form new memories. Years of testing (the rest of his life) has offered great insights into the function of the hippocamus and its role in memory. The last example is similar to H.M. Clive Wearing a former world class musician suffered encephalitis caused by the herpes virus which bilaterally wiped his hippocampus. He currently displays profound amnesia and has been dubbed "memento" (later a movie by the same name).

These are just three examples of thousands which demonstrate the accuracy and the power of the lesion method. Lesions in all parts of the brain are able to demonstrate the power and the function of these certain areas. While it is interesting to think about how the lesion method can teach us, piece by piece how the brain functions, it is also interesting to look at lesions in children. It appears that children are often able to recover and cope with the loss of certain brain areas fairly well. It is amazing to think about the plasticity and the adaptability of the brain at a young age.

The University of Iowa has the largest database of lesion patients. With the collaboration of the University Hospital and the patients themselves, the college is able to watch, learn and research with these interesting cases of the brain. It will be interesting to see what the lesion method can teach me.

Lesions

One of the ways that we lose our mental abilities is through the development of brain lesions. Whether from

Sunday, May 24, 2009

AI

Today's post will be short, but I will pick up the topic sometime soon. I don't have much time since it takes about six hours to celebrate four years of work. I'm graduating!

I have heard a lot of speculation about the new Terminator Salvation movie and have started thinking more about AI. This spring I took Intro to Computer Science as well as Philosophy of the Mind. Almost the perfect combination for talking about AI. In terminator, there is a computer, Skynet which becomes self-aware and decides to terminate the human race with an army of terminators. While this movie may have been made just to entertain us with action and adventure, it does raise some valid questions about the future of humans and our relationship with technology.

According to Moore's law, the rate of computing power growth is exponential and describes the long-term trend of many different computing functions. Mankind has never seen something with this growth pattern that has lasted this long. There is increasing belief that this growth pattern is heading toward "the singularity", the point at which this accelerating change creates superintelligence. It has been theorized that after the singularity, intelligent technology will begin to produce more intelligent technology at a pace more rapid than humans. While this post is not meant to sound prophetic, it is only a look to the future. I find the mind so interesting, that to be able to explore artificial minds would be a wonder.

There will be more to come soon about AI, but for now I have to go graduate.

Saturday, May 23, 2009

Humor - You Make Me Smile

With most of the posts so far, I have either read a couple books or articles or been able to follow some sort of outline of experience with the topic. Here however, that will all change. What makes us smile? Why do we laugh? For what reason did we evolve humor? Why does laughing make me feel so good? Are funny people more attractive because of the way they make others feel? Why are some things funny to some people and not to others?

I love to laugh. I also love people that make me smile. It is amazing to find someone that you just can't stop smiling because of. I think humor and laughter are one of the closest things that we can share with someone. To be able to appreciate or have a similar sense of humor as someone means that you are probably very similar to that person in some sense. I often find that people look for friends that have a similar sense of humor as them. It's odd how we can bond over something that people may call frivolous or silly. Is the purpose of laughter to help us to relax, to make us happy, to put us at ease? The smile seems to be a cross-cultural sign of happiness and openness. So it seems that laughter is born into us.

However, how does laughter and humor actually work in the brain? To be honest, I have no idea (not to say that I have a real grasp on the other topics). If I was to guess, I would say that there would be some higher order cortical reasoning, perhaps in the frontal lobes combined with limbic system activation. But, sometimes when I study or think about something like this, I wonder if I do really want to know. Does learning about how something exactly works give a more full appreciation of something? I often say that I don't want to learn about something because it takes away from the fun and the mysterious aspects. Santa Claus is a lot more fun and intriguing when he is a jolly old man who flies reindeer and lives in the North Pole than when he is your parents. I guess this raises some of the ethical questions regarding neuroscience. Do we want to pinpoint areas in the brain that tell us someone is lying, a racist, ect.? There is a huge power in uncovering the inner workings of the mind. It has been protected by the other minds problem for years. How do we truly know that other people have minds and that they work like my own? By uncovering the mysteries of the mind, we are not only saying that other people have minds, but we are showing exactly how they work and what they are doing.

While these questions are raised, I am too curious to be detered by losing the mystery of the mind. While losing the mystery, it will be far to interesting to see what we can't now. It may also only open up a new realm of questions and mystery. How can we know when the search is over? It is so interesting to at least think that there is an infinite number of possibilities to study and research in the mind. So while I love to laugh and be humerous, today I can just live with that, however, tomorrow perhaps, I will look into how it works.

Smile - Robert Randolph and the Family Band

Friday, May 22, 2009

Scent

What really makes a memory vivid in your mind? Most of the memories that I have, I can remember what I see, sometimes I can remember some things that I heard. But the memories that are the most lifelike are the ones in which I can remember the smells. The sense of smell, olfaction is closely related to taste and also has a very strong influence on emotions. However, beyond these functions smell is also essential for finding food, avoiding dangerous things and finding a mate. I think that smell is often the most overlooked sense that we possess. If you have ever asked someone what sense they would give up, it is often between taste and smell for the sense that is given up. Often people don't recognize the importance or the experience of smell until they are sick and have a stuffed nose. I want to take the time now and talk about how important this sense is to me.

I first started to understand the importance of smell a few years ago when I read the book, The Emperor of Scent. The story describes a scientist (who is also a connoisseur of the nose) proposing a theory about how we smell and the process that he goes through to publish and also propose his theory to the scent makers. It was here that I began to recognize all that I take my sense of smell for granted for.

Olfaction actually occurs through the binding of molecules to the olfactory epithelium. This ligands stimulate olfactory receptors on the dendrites of olfactory receptor neurons. This occurs either through diffusion or through binding to specific proteins. This action triggers a cascade of second messengers mediated through g-proteins. The specific pattern of conformational changes of the proteins paired with the specific pattern of chemical changes maps onto a cognitive map of axonal activation which describes a broad range of aromas. The activation of certain projections will produce the sense of different smells depending on which projections are stimulated or depressed. The sense of smell is interesting because to some extent it is the only sense which uses direct stimulation of the nerves. The projections of the olfactory neurons combine to form the olfactory nerve. The synapsing of the projections in the olfactory bulb begin the process of divergence for the projections of the olfactory system. Some projections continue on to the olfactory cortex, while others converge into glomeruli which are composed of Mitral cells. These cells synapse onto five other area of the cerebrum, including most importantly the amygdala and the entorhinal cortex. The entorhinal cortex projects to the amygdala which is involved in the emotion of the sense of smell and it also projects to the hippocampus which is involved in the memory of smell. The close ties of the olfactory system with the limbic and memory systems place the importance of smell in emotional and place memory.

Before going into deeper detail here, I want to mention some of the other functions of smell. Combining the sense of smell with the sense of taste produces flavor. It is amazing to think that there are essentially five different tastes but hundreds of smells, thus to produce a certain flavor, a different combination of smells is used with a base layer of tastes. This technique of alteration is how we are able to produce countless numbers of candies and soft drinks.

Another important function of olfaction is the detection of pheromones. Pheromones are a chemical signature which causes a reaction in other members of a species. Related to humans, I speak of sexual pheromones. During ovulation a women's sense of smell is the strongest. This relates to the results that olfaction is used to detect the MHC genes which are useful in the immune system. Partners look for a partner to have a different MHC gene combination so as to strengthen the immune system of their offspring.

Back to the emotional and memory connections of smell. Its odd how a quick whiff of a smell can almost literally transport you back in time to a specific memory. The use of smells in certain situations seems to take advantage of the emotional connections of smell and memory. From the use of perfume or cologne for special occasions or the cooking of special meals for occasions help to strengthen memories by using this olfactory pathway which connects the amygdala and the other memory systems. Smell seems to be the only other sense which can elicit such strong memories in my mind besides hearing, specifically music. There are a few songs which seem to be able to take me back to a memory, but it is the smell of certain odors which seem to bring me back and almost relive a memory. While the perception of smell is not understood completely, it will be very interesting to uncover the mysteries of the sense. It is interesting however, to take advantage of the effects of smell on memory, one that can be useful creating great memories for life.

That Smell - Lynyrd Skynyrd

Thursday, May 21, 2009

Beliefs and Finding Truth

How do we believe in our knowledge or the facts which we hold true? What leads me to believe in something? Are there certain inherent truths which make some things more believable than others? Belief is often treated as a simple from of mental representation and is part of the earliest parts of conscious thought. In an earlier post I mentioned the possibility of the existence of thoughts which do not necessarily have the physical control of neurons and which are instead controlled by thoughts themselves. This has a large impact on neuroscience, because if the concept of belief is incoherent or indefensible then any attempt to find the underlying neural processes which support it will fail. To find an area of the brain that is responsible for belief would be very political and potentially problematic in nature. If one is able to manipulate someone's beliefs or one is able to provide evidence for certain beliefs being only in our head, ramifications would spread far beyond just the discovery of something very interesting.

I actually started thinking about this topic because I stumbled across a documentary about the occult and magic. I wonder what it is about illusions or what people say that makes us believe in them. This then reminded me have a paper I read recently entitled, "Scientists See God on the Brain." Essentially parts of the brain are more active while thinking about religious beliefs. I also found a related article here in which SPECT was used to determine regions of the brain which responded to altered states of consciousness during prayer and deep meditation.

So, is belief something that is simply caused by the activity of certain brain regions. Is a belief in something a sort of self deception sometimes or a way for the brain to try to make sense of what is occurring in the world? What makes beliefs so hard to let go? Is it that we have put our faith and trust into something that we cannot allow ourselves to think that we are wrong? Is is because our brains have wired the beliefs into our selves?

So my basic question about beliefs are whether they are formed by processes in the brain or whether they are created in the mind. If they are created in the brain, does that take away from beliefs? Is a thought which is just a pattern of neural activity somehow less personal? We would like to think that our believes are something that is earnest and something that we are truly connected to. This leads us to want to believe that our beliefs are created in the mind and part of something that is more than just biological. For many people, belief in something creates a foundation from which they can live out the rest of their lives. While I have my beliefs and thoughts on things, to me they are my opinions and if they can be shown otherwise, I will try to change my thoughts.

I wonder what can make us believe certain things? Are there things that you don't know why you believe in them? Are there things that you wish to be true but you doubt? I am not worried if beliefs are a combination of neural processes, I believe that they are there for a reason.

Belief - John Mayer

Thinking Thoughts

In the last paper that I wrote for my undergraduate education, I wrote on the mind-body problem. How are the mind and the body connected? How do they interact with each other? However, while that might be the heart of the problem, for me, it raised other questions. In the paper I conclude that the mind arises from the physical processes of the brain and that there are emergent properties which are created in the mind which would not necessarily be predicted in the simple physical processes. So from this conclusion, I wonder how some thoughts and feelings are created.

Are there thoughts or ideas that can then be created by the emergent properties of the mind and not be directly traced back to physical causes?
How do you understand thoughts that are not directly caused by physical means?
What are some examples of these thoughts?
Could one example be how do we miss someone?

As humans, we naturally believe ourselves to be better than other creatures and thus like to believe that we are the only animals to have some of the cognitive abilities that we have. It is these abilities that we would naturally like to apply to the emergent properties of the mind. I wonder whether this is actually true or not. It is interesting to wonder what thoughts we have that might be created by other thoughts.

I want to explore missing someone. We have thoughts about a person, different feelings, experiences, memories, opinions, ect. But it is not these that actually make us miss them. There are thoughts about these are thoughts. What is it to miss someone, a wish for someone to be with or near you? How long does it take for a person to be gone to miss them? Can you miss someone who is with you? When you miss a person, you have a wish or a desire for that person which is not fulfilled. We may assume that there could be a biological basis behind having thoughts about wanting something and feeling bad for not having that thing. However with a person, I think that there is so much more. There is reflection and thinking about that person which brings to mind the reasons why you may miss them. When thinking about these reasons, and realizing that the impetus of those memories or thoughts isn't there creates a feeling of loss. So while I concluded that the mind arises from the brain, it appears that there are emergent properties of the mind that can inturn interact with the brain. It is interesting how these good thoughts and memories when combined with a person not being there can make someone feel not as good, to make them feel that the miss someone.

I'll end this post by attaching my paper...

Bridging the Mind/Body Gap?

The mind-body problem may be one of the oldest problems in the philosophy of the mind. In its most general form, the problem arises from the description of the relationship between the mind and the body (brain). Generally philosophers have gone one of two ways, by claiming either a physical or nonphysical connection in this relationship. Theses answers to the question of how the brain and mind interact are broadly addressed by dualism (nonphysical), monism (physical) and phenomenology (focuses on experience). At stake to answering the question of the mind-body problem are consequences to how we frame and answer questions related to what is a person/what is an identity, do we have free will, and what is the self. In the hundreds of years, since Descartes formally posed this question, many theories have proposed solution to the problem. Dualism (as an umbrella term for related theories), favored by Descartes, monism (including the physical theories) and phenomenological theories have been proposed as solutions to the problem. However, none of these alone provide a satisfactory answer to the question nor resolve the problem. It is proposed here, however, that an explanation of the mind-body problem does exist. By first recognizing a linguistics problem in the way that the problem is posed and then adopting an emergent biological naturalistic approach to the problem, we find a theory, “eliminative materialism,” which is both satisfactory and that resolves the problem.
When a theory is described as “satisfactory” and “resolving” one must be careful to describe the connotations and implications of what that means. Here satisfactory is taken to mean that the theory is not perfect in all respects, however, as a whole, or along the right lines the theory is correct. Resolving is thus taken to mean that a straightforward solution is provided by the theory at hand. The previous theories proposed as solutions have their respective supporters and doubters, but they all have flaws and problems that do not make them the best candidate for solving the mind-body problem. Although the theory here may have its doubters, it provides a concrete and realistic explanation of how the mind and body relate.
The main issue or contention with the mind-body problem is not definitively how the mind and body relate, but in whatever way that they do meet, how does this affect other parts of life and person. There are many different subjects that are discussed in the philosophy of the mind, including but not limited to, death, perception, personhood, emotion, free will and the self. When adopting a certain frame of the mind-body problem, certain restraints are placed upon you in how you view and perceive these related topics. It is difficult to adopt a position and be able to defend all parts of what we often hold special as humans with just that position. The variety of theories of the mind-body problem appear to have various tradeoffs based on their strengths and weaknesses in describing the relationship at interest. The problem of the mind-body problem appears to be that as humans, we want our cake and to eat it to. This anthropocentric view of human kind as being special beings means that we want everything to work as we wish it. Man wants to consider himself special, as he is the only one to be born or possess this special characteristic of consciousness, unwilling to assign it to creatures or objects, not like himself. Most people believe that they want to be responsible for the choices that they make, that they know that other people are themselves conscious and that it is not through a serious of miracles that we live our everyday lives.
Specifically related to free will, it is generally contested that monists (who view the mind and body as arising from the same substance) follow a path which leads to determinism, which states that decisions are determined by natural laws, which would indicate that people are not free (in their decision making). Dualists on the other hand, view the mind and body as separate thus allowing for the mind to act independent of the body and thus act upon it. However, if the mind is separate from the body, and the mind only interacts with one specific body, how do we know that other people are conscious creatures like ourselves? Phenomenology on the other hand, brackets the questions that are largely at stake in the mind-body problem and instead attempts to offer an objective description of experiences. So until this point it appears when choosing a theory of the mind-body problem, one has to be mindful of the tradeoffs made in choosing a certain theory. The following theory proposes satisfactorily a resolution to the mind-body problem.
Since each attempt to answer the mind-body problem encounters substantial problems, it is of contention that perhaps there is a misunderstanding of the conceptual framework of the problem. It is perhaps not a “problem” it may be that the mind and body are the same thing, not necessarily in the ways described in monism, but in that the human experience can be described in metal and physical terms. It becomes a problem when the descriptions are used interchangeably or in the field opposite of where they should describe. This view is similar to the mind-brain identity theory in that the mind and brain are viewed as two sides of the same token. The example of sense (mental) and reference (physical) is used to describe this theory.
At this point in the theory we understand that the mental and physical are two sides to the same concept. However, it is the contention of this theory that it is the physical from which the mental emerges. Here one might confuse this point as Hasker’s middle way, “emergent dualism”, however, it is actually the inverse, “emergent materialism.” One can view the conscious from the top down or the bottom up. In the first of many analogies, a fire can be viewed from above and be seen as smoke, which is analogous to the mental states, or one can view a fire from the ground and see it as a fire, the physical. Many have heard the phase, “there is no smoke without a fire,” and in this analogy, it means that there can be no mental states without the physical. While this does not directly go back the other way, the physical does depend on the mental states which are them selves physical. By not placing the mental outside of the realm of the physical, it can be stated that the mental and physical interact. Another analogy for emergentism is that of water. When hydrogen and oxygen gases combine to form liquid water, new properties emerge that would not have been predicted from the materials that it emerged from. Thus the physical properties of the brain give rise to the mental states.
In Hasker’s middle way he decides to reject materialism, stating that materialism cannot account for a unity of consciousness if consciousness is simply neurons firing synchronously. However, in this present theory, biological materialism is fully supported. It is the view of this theory that mental phenomena are caused by neurobiological processes in the brain and that the brain is able to produce intentionality. Although the process about how this occurs is not exactly known, it should not be assumed that we will never know. McGinn states that we cannot resolve the mystery of the mind-brain problem. Although he too supports a naturalistic approach to how consciousness arises, he claims that cognitive closure does not allow us to ever fully grasp the mind-body connection (more on this later). Two propositions for how consciousness arises are proposed in the present theory. In one view, there is a specific coalition of neurons which act and fire in a specific way for stimuli both in the environment and internally. In the other view, neurons in the brain fire in synchrony and assemble to arise as a cohesive units from moment to moment while incorporating feedback from the body.
It is the argument of this essay that “emergent materialism” is a theory that is sufficient and resolves the mind-body problem. To summarize the argument of the theory, one should be reminded of the three parts that compose the theory. First, “emergent materialism” states that there is a linguistic problem with how the mind-body problem is stated and that from this linguistic problem arises a misunderstanding in how questions and answers are framed. Second, a materialist position is taken in this theory, meaning that it is believed that the mind arises from the physical brain. This point leads to the last point of the theory. The actions that produce the mind, produce an emergent property of the mind which is different from the properties which are actually creating the mind. The mind and its emergent properties then feedback and affect the properties and materials that give rise to it.
Any time that a new theory is proposed in any realm, it is often met with skepticism, and it will be the point of the rest of the essay to explain how this theory is better than the other theories of mind and also how it satisfactorily resolves the mind-body problem. When considering the other theories of mind, the author first rejects the notion of any theory that has dualist notions. Dualism fails to resolve the problem because its answer is fielded in an area which can neither be confirmed nor rejected. By placing the possibilities of an answer outside of the physical realm, where measurements and observations cannot be made, we can neither confirm nor deny the correctness of this theory. This makes the theory unsatisfactory as an explanation when its validity cannot be tested. While “eliminative materialism” takes a materialist approach to addressing the mind-body problem, it does not necessarily agree with the other materialist theories. They were insufficient in their attempts to explain the problem and also generally were met with criticism for not addressing free will. Lastly, the author will not address the phenomenological approach to the mind-body problem. This approach “brackets out” the questions at hand and instead concerns itself with the description of our experience. When the theory does not concern itself with the question at hand, the relationship of the mind and body, the author does not find as a sufficient explanation of the problem.
With the rejection of these theories, similar criticisms may be stated against “eliminative materialism,” however, the theory stands up to the criticism. Since the theory is rooted in materialism, the same criticisms of materialism should be addressed for this theory. The most common criticism of materialism is the failure to acknowledge and account for free will. The present theory addresses these through the terminology of emergentism. Since the mind emerges from the brain, and through this process of emergentism gains properties which are not of the physical properties that create the mind. It is through this creation process that the mind gains the possibility to have free will. This is now a physical explanation that is not deterministic which accounts for free will and does not use dualist notions of the physical and non-physical interacting. One other objection to the theory is that we do not know the exact methods by which the brain creates the mind. This issue is addressed by McGinn who states that we will cannot grasp how the mind and body are connected. He states that cognitive closure prevents us from ever knowing how the mind works. However, to state that we will never no something is an interesting way to address the problem. By stating that the problem exists in the physical world, we are aware that we have the tools and the knowledge to measure the necessary variables included in consciousness. While the exact way that the mind and body are connected is not yet known, it is the impression of the author that this problem will be addressed soon.
In conclusion, it is proposed that “emergent materialism” is the theory that satisfactorily resolves the mind-body problem. Where other theories are faced with various criticisms for not satisfactorily answering the question at hand nor taking into account some of the consequences of how the mind-body problem is answered, “emergent materialism” faces the criticisms and is able to account for the consequences of how it frames the answer. By placing the mind and body as two sides to the same concept, the theory is able to argue for the justification of a materialist position of how the mind arises from the brain. The debate of how free will is then dealt with is acknowledged through the use of emergentism of the mind from the brain in which new properties are created when the physical properties of the brain combine to form the mind. This theory appears to fill in the holes present in past attempts to solve the mind-body problem. While the exact properties of how the mind arises from the physical brain are not yet know, research is on the doorstep to understanding how these relate.

Wednesday, May 20, 2009

Minds Thoughts

This is going to be a quick one today. I just am wondering if there is the possibility that there are thoughts that are simply created by the mind.

Tuesday, May 19, 2009

Measuring the Mind

The are hundreds of ways in which we measure varying parts and functions of the human body. With almost all of them, we can say, "because this is happening, these other things are happening." While that was not very eloquently stated, the point of it is describe how we are not exactly sure what the measurements of the brain mean. To elucidate the point further, take heart rate for example. We can measure the heart rate and state that a higher rate means that the heart is pumping blood more quickly, while a slower heart rate means that the heart is pumping blood more slowly. There are many different techniques to measure the activity of the brain, but what does each of them say about what is occurring in the mind?

There are really two different ways to go about measuring the brain, structurally and functionally. To measure the brain structurally, there are a few different techniques including MRI and CAT/CT scans. MRI uses magnetic fields to detect radiation from certain molecules which are present at varying levels in different tissues. The fluid contrast between structures in the brain can be visualized and is helpful in viewing brain neuroanatomy. A CAT/CT scan on the other hand uses x-rays to produce an image of the brain. While these measures of the brain are interesting and can demonstrate information about the structures or abnormalities of the brain itself, it does not show us how the brain is actually functioning.

Functional imaging of the brain does help to elucidate how the brain is functioning. To view images of activated brain regions by detecting the indirect effects of neural activity on local blood volume, flow, and oxygen saturation, you can use fMRI. To measure brain activity, you can you EEG. However, what are these actually telling us? A rise in blood volume, meaning greater activity, meaning that the brain area had more neural activation at the time that the measurement was taken as compared to the baseline measurement. How do we know that the baseline measurement is actually an average measure of the brain activity? How do we know that a change from baseline necessarrily means a correlation between that brain area and the task or the measurement that is occuring. The difference in the wiring of people's minds also has to play apart in how different people accomplish the same task. There seems to be inherent problems in using these techniques and observing the behavioral outputs as correlates. I believe that an effort to lessen the time scale of these measurements, as well as the use of hybrid models, in which multiple techniques are tested against eachother will be helpful in actually pinpointing what is occuring in the brain.

This summer as I start my Ph. D. program and venture into the world of these functional scans, I hope to keep on ongoing dialogue about what these scans are actually telling us. I remember a story last year, in which statistical significance was found in a "noise" and that that raises questions of the validity of using these scans to draw some conclusions. It will be interesting to always ask about the reliability of the test. While I think that it is a very powerful tool, it is one that needs refining and also one that needs to be used with other methods. As of now I am somewhat apprenhensive about what the scans are actually telling us, but only time will tell.

The brain controls all that we do through the communication of neurons, the changes in firing rates, the changes in the strengths of connections between neurons, and the release of chemical messengers, and hormones all change how are brain functions and what it is trying to accomplish. But what do the changes mean? A rise in a neurotransmitter here, an increase in firing there. These changes are occurring on a time scale of milliseconds, while our measurements are occurring on a much different time scale. While the brain is accoplishing all these physiological activities it is important to remember what is arising from these activities, the mind. We must not forget that while we may be able to measure what the brain is doing, we still have much further to go before we measure what is occuring in the mind. Through contemplation and self reflection we can investigate our own minds. However, this topic can have a post of its own at a later time.

Monday, May 18, 2009

Decision Making

Decision making is a series of cognitive processes which lead to the selection of a course of action among several alternatives. Everyday we make thousands of decisions, although we may not always recognize that we are actively making a decision at that moment. Before getting to far into this, I should start with some questions.
What makes a "good" or a "bad" decision?
What leads us to making a decision?
How does emotion affect decisions?
Are some decisions made for us based on biological predisposition?

The anterior cingulate gyrus and the orbitofrontal cortex are brain regions involved in decision making processes. A recent neuroimaging study, found distinctive patterns of neural activation in these regions depending on whether decisions were made on the basis of personal volition or following directions from someone else.

Another recent study found that lesions to the anterior cingulate gyrus in the Macaque resulted in impaired decision making in the long run of reinforcement guided tasks suggesting that the ACC is responsible for evaluating past reinforcement information and guiding future action.

Emotion appears to aid the decision making process: Decision making often occurs in the face of uncertainty about whether one's choices will lead to benefit or harm. An interaction between emotions and the body states that they cause along with further interaction between the decision making processes. I can understand "rash decisions" this way. Where emotions and the current body state, affect or cloud your ability to make decisions.

Whether we make a decision or not is one thing, but it is not always the decision making that call into question, it is the consequences of our actions. How do we measure a "good" or "bad" decision? Is it how its consequences affect us, how it effects others? It seems that when we are asking whether a decision was good or bad, it is because its effects had an impact in many areas, perhaps including some moral. Decisions seem to be some of the most subjective experiences that we have and often times are are one of the cognitive actions that affect other people. So what guides me in making a decision? My experiences, my volition, my beliefs, the current situation, my emotions and activation of a neural circuit are what guides my decisions. I feel that decisions cannot be judged as good or bad, but the situation and the overall effects of the decision have to be taken into account.

When we start to talk about the morality of decisions and how one should be judged for the decision they made, we start to enter a fairly uncertain, indescribable area of the human mind. It is areas like this where you can really begin to marvel at the power of the mind.

Sunday, May 17, 2009

Emotions - Attractions - Feelings

To begin the posts of reflection, I thought that I would start with something that has been of relative importance within the last few weeks. It started with my philosophy class (Philosophy of the Mind) and was also piqued by two important relationships in my life. This topic is care, and more specifically love. The book in my philosophy class was the Reasons of Love, by Harry Frankfurt. I started thinking that whether we care or not or for what reasons we choose to care about particular objects or people is interesting, but how is this guided within the brain. People often speak of loving with their hearts, does this indicate that these feelings are not guided by conscious thought, but rather something more instinctual. Are we biased, towards caring about or being interested in certain things without any control? Or, are there certain processes that occur in the brain that allows us to develop feelings about particular things?

Some neurobiological theories suppose that the limbic system is the seat of emotions. Certain patterns of neurochemicals in particular areas of the brain generate the physiological reactions of feeling or caring. Emotions are thought to be related to activity in brain areas that direct our attention, motivate our behavior, and determine the significance of what is going on around us. While these neurobiological reactions will have their effects, it is not enough for me to believe that because I receive a flood of NE or Dopamine everytime that I see someone or something that it will make me love that thing or want it. I want to believe that there are some cognitive reflections about why I feel this or that way. How can physiologic symptomology turn into or create certain indescribable feelings or emotions? It is a wonder that we are able to have this large range of emotions which are both physiogical and psychological in nature.

In terms of the other part that was helped in creating this post, I wrote the following about beginning a relationship with someone a few months ago.
"When you meet someone and start to fall for them, the chemicals in your brain actually change. I know that this may be a little neuroscience “geeky” but it is but one of the awesome and amazing things about the brain. When I see you and I get the butterflies in my stomach, sweaty palms, and flushed skin, it is due to increased levels of dopamine (“the pleasure chemical”), an increase in norepinephrine (which stimulates the production of adrenalin), and in phenylethylamine (causes faster firing of cells in the brain). As we become more addicted to the feelings that these chemicals produce the more we fall for the person that is causing these actions. But there’s more, and don’t worry I’ll explain the reason for including all of this. There is another chemical called oxytoxin, which causes a person to want to be physically held and have close contact, it can be stimulated by the simple glance of a lover, or a gentle hand hold. Lastly, sad but true, chemical effects wear off, or more aptly put, the body adjusts to the increase in these chemicals. Do you know why a lot of relationships end after six months, it is because the infatuation chemicals’ effects wear off and the people realize that they don’t have a deep connection with the other person. This is where endorphins come into play. They make a relationship steadier, intimate, dependable, warm and a great sharing experience. It is not the same giddy high, but a calmness and stability. But there is good news, this is the chemical that keeps people together and it is also highly addictive, with a resistance to adaptation. So to summarize, the infatuation love, is the passionate, exciting love, where as endorphins produce the love of loving someone."

It amazes me the way that people are able to elicit a chemical storm in our bodies through somthing as simple as a knowing glance or a gentle touch on the arm. It is also amazing how much we embody their reciprocal emotions. Returning to the Frankfurt book, he states that one must love something before they can love themselves, and that after they love themselves, they can begin to love other things. I take this to mean that one must love themselves to share those feelings and emotions with others. Also returning to an earlier topic, how do we begin to like things. I believe that we find rewarding experience or pleasure in something or see something that reminds us of ourselves, or brings about the best in ourselves and we want to spend more time with that thing or person. It is always so exciting to begin to find something new that has these begginning feelings. I like the giddyness. At the same time, what happens at the end of a relationship with a person? How has the combination of cognitive and neurobiological signals changed? Is there a such a thing as emotions in reverse?

So where does this bring me in neuroscience? I am interested to see what changes in the brain or what is different in the brain between different emotions. Parsing apart love to reveal different types of love would also be interesting. I hope to look further into the cognitive and neurobiogical aspects of emotion and language and how we express our feelings. While searching the mind is difficult in itself, it is even more of a wonder to forge through a tangle of ever changing emotions.

Saturday, May 16, 2009

First Questions...

How is that the human mind is so intriguing to itself? The brain appears to be intrinsically interested in itself and how it works. I have been fascinated with the brain since I was in sixth grade. For our science project, I wrote and essay and presented a poster on the human brain, "the 3 pound lump of mush in our heads that controls all that we do" (Kurczek, 1998). At times we seem to take for granted all that our brain is capable of and what we are able to accomplish with it. It almost seems as though we actually care about the brain more when it isn't working than when it is.

This brings up another reason for my interest in the brain. These disorders of the brain have been widely available in my family. From epilepsy, to brain cancer, to Parkinson's and Alzehiemer's, my family appears to have run the gambit of brain aflictions. These problems and other disorders are some of the most interesting cases of diseases in our world. Nothing is more personal than your own brain turning against you. To be fighting the very thing that is you, I cannot imagine the feeling of watching and experience yourself, lose yourself.

It is the personal nature of the brain, the ready availableness and the constant experience that makes the study of the brain so appealing. The questions of the mind and brain have perplexed some of the most intelligent people in the history of mankind.

What is consciousness?
How do we know others are conscious?
What is language, how do we learn it?
What is learning and how do we store memories?
What is sleep and dreaming for?
How and why do illusions occur?
How is the brain able to adapt itself to injuries?
Can we see thought?
Do we have free will?
How do we think, feel emotions, love, experience pain or sensations?
How can the brain turn against itself with the variety of disorders?
Are certain people doomed to be a certain way because of how their brain is wired?

While the purpose of this is to ask questions, hopefully there may be a smattering of answers. With this blog I'll explore my own experiences and thoughts to reflect on these questions as well as the countless others that are bound to turn up. It is amazing to think that there may exist the possibility that something can figure its very self out. While I may not figure out these questions, it is exciting to be on forefront of experimentation, at the edge of current human knowledge as we look to the abyss that is the mind and boldly take step after step as we continue to search the mind.