Hormones

In 9^th grade, when I was 14, my rather poor running technique caused me to develop shin splints after only a week or two in gym class.  One trip to the doctor later, and I was prescribed a mild steroid to treat the feeling of knives digging into my shins. 

I don’t particularly remember what steroid it was specifically, nor do I have concrete memory of how it was administered (though I believe it was in pill form).  In any case, taking this anonymous steroid certainly diminished the pain of walking significantly, though I began to notice other, mild changes in my behavior.  Now, one could possibly chalk this up to the placebo effect and my prior expectations of what steroids do (I remember thinking it was strange and oddly funny that I was taking steroids), but I definitely noticed little things.  I remember being more irritable, and I was less inhibited in trying the more “macho” aspects of gym class. 

Again, these were mild steroids, so the effects probably wouldn’t have been anything too significant.  Certainly, I didn’t experience anything close to “’roid rage,” but I was still happy to finally get off of them once my shin splints healed, and my mood seemed to improve noticeably.

A Brief Overview of Emotion

It seems that the answer to the question “what is emotion?” changes depending upon the perspective invoked.  From the perspective of the layman, emotion encompasses various states of mind from happy and sad to angry and fearful.  Explaining what emotions are usually seems to elicit a description of experiencing these feelings without a hypothesis as to what underlies them.

Of course, there are other, more intricate perspectives which are too numerous to explore here.  However, it is perhaps most appropriate to consider emotions from a neuroscientific standpoint, and I think any scientifically useful definition of emotion must draw upon its neurological underpinnings.  The issue is hardly settled, but I’ve seen theories explaining emotion as cognitive interpretations of bodily states as well as heuristics that provide information or motivation without having to refer directly to conscious cognition.  As to whether emotions arise from interpretations of bodily states or are the result of cognitive processes causing these states, I do not know enough to speak.  However, the heuristic model of emotion seems to make sense from an evolutionary perspective.  For example, it would seem more adaptive for an organism to experience fear immediately and react to that motivation rather than having to reason through the situation before responding.

In any case, I believe that a definition of emotion must involve an evolutionary understanding of its function (from its possible role as a social signal as well as its role in motivating action) as well as an understanding of the underlying biology and neurobiology.  

Visual Perceptual Learning via Inception

Well, it looks like Chris Nolan might have been on to something: it appears that learning via inception may actually be possible.  

In this experiment, Shibata et al. used an fMRI online-feedback method to induce visual perceptual learning (VPL) in the absence of real and specific target stimuli.  This online-feedback method recorded "activation patterns corresponding to the pattern evoked by the presentation of a real and specific target orientation stimulus" in order to repeatedly induce similar patterns in participants without their knowledge of what was being learned and without external stimulus presentation.  Participants were subsequently able to perform better in an orientation discrimination task, demonstrating a causal link between induced specific neural activity patterns and VPL.

It’s hard to read this paper without wanting to shout "Inception!", but even the researchers seem to have realized this implication.  In the final paragraph, they say that this fMRI neurofeedback method can "'incept' a person to acquire new learning, skills, or memory."  I personally hesitate in touting the implications of this paper for the types of learning the authors note, however.  It would seem that the ability to "incept" such learning depends on the plasticity of the region of the adult cortex in question, and it is an open question—perhaps out of my own ignorance—as to how plastic certain cortical areas actually are.

The application of this method to other areas of the brain, if possible, would carry significant ethical ramifications: while it would certainly be admirable to augment the brain in such a way that a person could learn more, it could feasibly be used to incept certain maleficent ideas into participants.  Nonetheless, this study is a fascinating example of the possible uses of fMRI technology to do more than simply record brain data.

Ghost from the Machine: A Sketch of an Ideal Brain Scanner

                

If given the opportunity to design any brain- or mind-reading device, it would be difficult to restrain oneself from creating an ideal scanner unconstrained by the limitations of current technology.  To that end, my device would render the highest spatial and temporal resolution possible, and it would not, through some miracle of technology, sacrifice one for the other.  It would essentially be able to read brain activity in real time as well as locate the activity with utmost precision.

 

                I admit that I don’t have the technical expertise to suggest its mechanism with certainty, but I have a hunch it would be based upon measuring the brain’s electrical activity.  It would be a direct measure, similar to an EEG, but the device would be able to locate this activity with a high degree of precision similar to an fMRI.  However, it would avoid the problems inherent in fMRI readings, specifically the fact that fMRI merely measures the correlation between brain activity and blood flow.

                With a sufficiently advanced degree of precision and knowledge about the brain, it is conceivable that the device could read conscious thought from brain activity.  The advantages of such a device are innumerable and would conceivably allow us, with enough time and experiments, to unlock all or nearly all the secrets of the brain.  We could, for instance, measure the brain activity related to a certain task and determine which aspects of this activity contribute to conscious experience and which are effectively subconscious.  Whether such a device is realistic now or at any point is an open question, but the increasing growth rate of technological sophistication provides plausible enough grounds to think that we can at least approximate this ideal some day.

Derek Paravicini

                

                Since I don’t personally know anyone with a brain injury or disorder, this week I turn instead to the fascinating case of Derek Paravicini.  Derek is perhaps the archetypal idiot savant: he is a prodigiously gifted musician who, while being extraordinarily adept at the piano and possessing an exceptional ear for music, otherwise suffers extreme cognitive and motor impairments.

                Derek is fascinating primarily for the duality of his condition and what it offers to the curious neuroscientist.  His most notable gift is his impeccable ear and seemingly endless ability to assimilate musical idioms.  He can reportedly recall from memory any piece he has ever heard and play it on piano.  Even more astounding, he can interpret the pieces he plays dynamically, taking audience requests and reinterpreting, say, “The Girl from Ipanema” as a Beethoven scherzo.  Furthermore, he has the fine motor control necessary to play the panorama of pieces in his repertoire and the requisite working memory to remember how to play them.

                Of course, these incredible gifts come at a severe cognitive cost.  Derek is blind and severely mentally disabled, showing an inability to remember his own age or even count properly.  More curiously, while he displays the precise motor control necessary to play piano exquisitely, he lacks the ability to perform simple tasks like buttoning the buttons on his shirt.

                It would of course be intriguing to see the inner workings of Derek’s brain to determine the neurological correlates of both his severe deficits and exceptional talents.  Would his prefrontal cortex be less developed than his primary audio cortex, say?  How would his primary motor strip be affected?  Sadly, these are as yet questions to which I can only speculate.

September 6th: Statistics, Journal Articles, and Confusion

                For me, one of the most consistently confusing things about reading empirical science journal articles is the abundance of references to statistical methods and models with which I have little familiarity.  This is generally more a product of my relatively elementary understanding of statistics than any fault of the researchers—though I expect that if they were in error, I probably wouldn’t be able to tell unless it were especially egregious.  I’ve only taken an AP Statistics class in high school, so once the subject matter goes beyond p-values, Bayes’ Theorem, and the like, I’m mostly lost; I find it difficult to understand a lot of the models proposed in the articles this week, for example.  I feel as if I have a good grasp of the conceptual aspects of basic statistics, but it’s certain that there’s more for me to learn.

                Furthermore, the manner in which most journal articles are written can occasionally interfere with my initial understanding of technical points, even if I am usually adept at grasping the main points of experimental design.  Now, I understand that the purpose of such papers is information rather than entertainment, but it often seems that the pervasiveness of passive voice and the density of field-specific jargon do much to obscure the more technical and subtle points in my mind.  Again, this has less to do with the authors—these characteristics are largely matters of journalistic convention—and more to do with the way I am accustomed to reading.  The disconnect between the thrill of scientific discovery and the occasional drudgery of reading journal articles is somewhat disappointing, however: I often wish that most science articles would read as excitingly as the content within, though this fancy is hardly important in light of the enlightenment these papers can provide.

Why Study Neuroscience?

My interest in the field stems from a desire, rooted in philosophy, to know how the brain constructs the world around it.  To that end, my interest in the neuroscience of social behavior arises largely from a preoccupation with the manner in which our brains influence the way we interact in and model social situations. 

My particular curiosity regarding the subject was first piqued when Dr. Harris delivered a guest lecture in my Neuro101 class.  The part of the lecture that remains most prominent in my mind involves how the brain often processes certain individuals—the homeless, drug addicts, and the like—as something less than human, neurologically speaking.  This type of dehumanization phenomena continues to fascinate me, for it offers potentially remarkable insight into how people are susceptible to violating personal codes of ethics and societal norms when faced with these social outcasts: if the brain literally does not process them with the same mechanisms as it does for those of a social in-group—if it does not process them as fully human—this neurological dehumanization makes it all the easier to mistreat them.  Naturally, I’m excited in what this class offers in regards to the prospect of further insights into how the brain constructs the world, particularly how this influences our perceptions of other individuals. 

Moreover, and more practically, I am interested in pursuing a thesis in neuroscience, and the methods-based aspects of this class should familiarize me with the various methods of the field.  In this way, I may have a more fertile intellectual ground from which to pursue a research question. 

Finally, and quite simply and sufficiently for me, neuroscience is fascinating.  Why not study it?