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Are humans unique?

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We have all interacted with animals, seen them at zoos, marveled at them (watching Nat Geo documentaries). If you are like me, you may have wondered whether they are programmed automatons (“fixed action patterns”) or alternately have a “rich” inner life (don’t accuse me of anthropomorphism just yet). I have always held they view that while animals are well adapted to survive their niches, they are able to do more than execute programmed actions.  Also, along the way, I have tired of the notion that “man was made in the image of God”, in the sense that humans are unique and special, given our extraordinary “cognitive” capacities. But then we humans have succumbed to “confirmation bias” by only looking at evidence that confirms this view (as in the tremendous achievements ranging from agriculture to space research). But we also need to review our history of violence and catalog our behaviors collectively as a species (witness terrorism, territoriality, in group/out group, biases, etc.,) and it becomes quickly evident that our “mental” apparatus has a lot in common with other species.

Frans de Waal argues, that this is indeed in the case, in his essay “What I learned from tickling apes” that appears in the NYTimes. Well worth a read. As always, I find it informative to also peruse the reader comments .

Social Neuroscience

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The 1990s were designated as the “decade of the brain”.  This spurred significant advances in basic brain research.  It also spawned a new discipline called cognitive sciences or cognitive neuroscience (a multidisciplinary approach to study brain function – yours truly was one of the early graduates of this fledgling field of study). A critical development out of this interdisciplinary approach was functional Magnetic Resonance Imaging (commonly referred to as fMRI). fMRI has proved to be a very important tool in advancing our knowledge of the brain. With this tool, researchers have been able to peer into functioning brains. Over the last two decades, there has been prolific output from a multitude of labs across the country and the world. Beautiful, psychedelic pictures of brain slices color coded by intensity of activity has filled the pages of journals and popular press.

That the human brain is highly modular in function has been known for a while (thanks to studies involving individuals with lesions in very specific regions of the brain – check books by Oliver Sacks for fascinating stories).  fMRI further reinforced this fact and extended it in important ways by revealing more nuanced modularity in the brain.

 

Alison Gopnik, a professor of psychology and philosophy at UC, Berkeley, has this to say in a recent article entitled – How the Brain Really Works  

 

For the last 20 years neuroscientists have shown us compelling pictures of brain areas “lighting up” when we see or hear, love or hate, plan or act. These studies were an important first step. But they also suggested a misleadingly simple view of how the brain works. They associated specific mental abilities with specific brain areas, in much the same way that phrenology, in the 19th century, claimed to associate psychological characteristics with skull shapes.”

Her insinuation is that this modern day phrenology is not sufficient to explain how the mind works. In fact, she goes on to cite some newer research that demonstrates multiple areas of the brain being engaged in certain activities. More importantly the pattern of activity changes depends on context and focus of attention. She writes

 

People often assume that knowing about the brain is all that you need to explain how the mind works, so that neuroscience will replace psychology. That may account for the curious popular enthusiasm for the phrenological “lighting up” studies. It is as if the very thought that something psychological is “in the brain” gives us a little explanatory frisson, even though we have known for at least a century that everything psychological is “in the brain” in some sense. But it would be just as accurate to say that knowing about the mind explains how the brain works.”

It turns out Gopnik is arguing for the importance of her own profession: Psychology, for brain research and making a case for why she should get a raise.

 

Joking apart, her arguments have important implications in a broader societal context. In a previous post, I wrote about neuroscience and the law.  There I warned about Neuromarketing. Now there is an established discipline called Neurocriminology. A psychiatry professor, Adrain Raine, has written a book called, the Anatomy of Violence. He has peered into the brains of murderers and found evidence for reduced functioning in certain brain areas compared to “normal” folks. The upshot is there is predisposition to violence in certain individuals and it can be picked up in brain scans. You can read his take in the article – Neurocriminology: Inside the Criminal Mind.  It tackles issues related to the implications of neurocriminological (that must be a new word) research for crime, punishment and the law. Very interesting. A interview with the author can also be heard on Fresh Air – Criminologist Believes Violent Behavior is Biological .  This is a must hear, Terri pins him down on his own contradictory beliefs vis-a-vis what his own research means.  Gazzaniga (cited in my previous blog- link above), has reviewed the book, and he offers this assessment

 

The belief that violent behavior can be explained—and needs to be understood—is certainly admirable. I join Mr. Raine in believing that it’s our duty to consider all of this research kind of interesting, even though it is going to take a long time to figure out how it all works. And I believe we can learn more about the biological mechanisms of violence, and that we may someday come up with interventions that help us predict with greater accuracy future antisocial behavior: Such knowledge would greatly enhance society’s ability to be more rational, even in such mundane procedures as parole hearings.

But we live in a layered world: There are the physical, the biological, the mental and the social layers, and each builds upon the last. At this point in history they interact in ways we don’t fully understand. Mr. Raine raises this issue, and urges us all to think hard about what steps we should take. When he suggests that we undertake action on the social level—the “top” layer—in order to prevent crime or prescribe individual interventions, I get off the train. In my view, someday, somehow, someone is going to figure out that the social layer simply can’t do all the things we ask of it.

Next stop, Social neuroscience?

Written by asterix98

May 6, 2013 at 3:55 am

Critical thinking.Anyone?

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“ . . . intelligence . . . is in plentiful supply . . . the scarce commodity is systematic training in critical thinking.” –Carl Sagan (requoted from How to become a Critical Thinker)

Recently, when browsing the Health pages of Google News, I was intrigued by the following headline in the sidebar – Couple Addicted to Coffee Enemas, Up to Four Times a Day! If you know anything about enemas, well, the obvious is easily imagined. It turns out this couple are participants in a reality show – My Strange Addiction on TLC. And it is in its fourth season!! Fourth !?! What’s on tap for this season? I quote from the article “….In its premiere of the first of eight new episodes on Feb. 13 at 10 p.m. ET, the show will also highlight Lisa, a middle-aged woman from Detroit who eats cat fur, grooming her pet with her own tongue. In subsequent episodes, a woman is addicted to bee stings and another one inhales more than 30 jars of vapor rub every week. In the season finale, a woman is addicted to drinking blood….”  Really!  The good news here is that there is not much collateral damage as these strange behaviors are restricted to the individuals or their families.

Which brings me to another topic – Preppers! Anybody watch Doomsday Preppers, the reality show on National Geographic channel, no less! A NYTimes article described the show thus “…is more or less a weekly invitation to laugh at lunatics tunneling into mountainsides to escape a Russian nuclear attack. ” Of course, there was a significant segment of the population obsessing over the ill-fated Mayan end-of-the world prediction. Now it gets a bit worrisome because we are talking about larger groups of people who could potentially influence others in their network to think like them and create panic. The potential for collateral damage is higher!

Which leads me to L.Ron Hubbard. I urge you to listen to this interview – Going Clear – on the Fresh Air Program hosted by NPRs Terri Gross. It gives you some great insights into the mind of Hubbard, Scientology, and its practitioners. Essentially, Hubbard’s fight with his own demons gave rise to this cult with no real basis for broad applicability of its tenets to create social good.

Which points to two modern day abusers of their reach and power, one peddles physical health and wellness, Dr.Mehmet Oz, and another peddles, spiritual health, Dr. Deepak Chopra. You can read about Oz’s shenanigans in the New Yorker article – The Operator – Is the most trusted doctor in America doing more harm than good?. From the article, it will be obvious that Oz is a cardiac surgeon with stellar credentials but also a man who gets carried away by his own success and succumbs to peddling advice (taking on a messianic persona) that is clearly outside of his expertise. Hence, the subtitle question. Clearly, lot of folks tune in to watch his show which means he ought to be more responsible. I came across Chopra’s book, back in the early 90s and kind of bought into his holistic medicine philosophy of curing patients, because it made sense. I sampled some of his writings over the years and quickly determined he was losing it. He has truly become, as one blog calls him, appropriately I might add, the King of Woo Woo. He is #72 on the Top 100 American Loons – a place well deserved. He was on KQED’s Forum program recently talking about his new book – SuperBrain . As usual with his gift of gab and condescending voice, he doles out a bunch of nonsense (which compelled me to write this). What is even more surprising, he has convinced academics from Harvard, CalTech, and other prestigious institutions to co-author books with him. This guy utters pure drivel. But then he has a huge following (I have watched him hold audiences in rapture and wondered why they cannot see through his blasphemy).

Which brings me to the main point of this note, the central importance and need for critical thinking in our lives. P.T.Barnum said there is a sucker born every minute. If you don’t want to be one of them, embrace critical thinking with earnest. Just in case someone needs it, there is a lovely primer on Critical Thinking (targeted for high school and college kids).

Written by asterix98

February 11, 2013 at 9:29 am

face recognition in the brain

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One of my heroes in the field of neuroscience is Wilder Penfield. He pioneered the use of electrical stimulation of the brain, prior to surgery for treating epilepsy. The goal was to identify brain functions in the areas surrounding the locus of epilepsy and spare as much tissue as possible, if critical functions had been identified. The most remarkable part of this exercise was that the patient was fully conscious (although under a local anesthetic) and could verbally report sensations and perceptions experienced by the electrical stimulation of the probes. This technique contributed enormously to deriving functional maps of the human brain.

Penfield’s legacy is alive and well.  A couple of days ago, ScienceNow website reported on a study published in the Journal of Neuroscience.  By using techniques similar to Penfield’s, scientists at Stanford Univ, were able to determine the precise locus of face recognition in humans. Huffington Post has also included a really remarkable video of the patient’s experience as he is being stimulated by electrical current.  You must watch it!

That our three pound universe is a constructed reality, is on ample display in the video. Soul theorists, go figure!

What lay people may not appreciate, in this story and the video, is that our ability to recognize faces is confined to a small piece of our cerebral cortex. Destroying this piece of brain tissue only knocks out face recognition. One can still recognize objects (in the video, the perception of the scientist’s suit and tie is not distorted.) In fact, back in graduate school, I had the privilege of meeting a person, who due to an accident in early childhood, lost the ability to recognize faces, even his own! His non-face object perception was intact. He used salient features like a mustache, glasses, or other unique feature to remember and identify people he met.

This study and the video gave me the cognitive high for the day.

Written by asterix98

October 25, 2012 at 6:24 am

The tell-tale human brain

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I just finished reading a book entitled “The tell-tale human brain” by V.S.Ramachandran. [For those of you who do not know the name, Ramachandran, is a world renowned neuroscientist. He is a remarkably gifted scientist and has conducted many path breaking studies that have significantly advanced the status quo in our understanding of the human brain. Some people even think he may be a Nobel prize candidate for his pioneering work in neuroscience]. His research is one of the contributing causes to the many neuroX subdisciplines (neurotheology, neuroeconomics, neuromarketing to name a few) that have mushroomed in academia and industry.

This book is a good synthesis of much of his research. If you ignore his not so great sense of humor and sometimes chest beating, there is a lot of great material in the book to ponder on. What I love about his books is his rich catalog of neurological patients and their attendant deficits. Through their abnormalities, we are lead to an understanding of the inner workings of a normal human brain.  My favorite is the “god center” located in the temporal lobes. Patients with temporal lobe epilepsies see visions of god!! [My advisor used to say, irreverently, that the claims of received wisdom from God are actually manifestations of a hallucinating brain. I must say I agree with him.]

Some of the topics include mirror neurons and their role in social cognition, neural plasticity, synesthesia (blending of the senses), impostors moms and dads. It is utterly fascinating when we consider the remarkable insight that our unified percept of the external reality is really the orchestration of many interacting functionally specific brain modules [the timing and sychronization of these processes are also extensively studied topics in neuroscience]. Blindsight, a phenomenon, described in some detail, will make you wonder about what we really mean when we talk about consciousness.

Ultimately, the book is about what sets humans apart in the animal kingdom. The book format allows the author to speculate a great deal. If you pick this book up, I urge you to do so with a fairly wide open mind.

Written by asterix98

August 3, 2011 at 2:38 pm

update-g&b

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On Dec.26th, 2010 I had a very interesting lunch/discussion with Margot/David Gleich/Niels vL on Google’s page ranking algorithm and its relevance as a possible framework for studying representation and retrieval in the brain.  Margot is exploring the idea of creating an interdisciplinary group at Stanford to study this further. Exciting! (In half-jest I told her I would sign-on as a post-doc.)

One of the topics of the discussion on synchronization in large scale networks. David Gleich is an expert in this area and helped some researchers, at Stanford Med School, model epilepsy (a case of synchronization gone wild!).  Fascinating subject.  Now I have a lot more to read.

I also threw this idea out to Bruno Olshausen, at the Redwood Neuroscience Institute. Should be interesting to see what he has to say.

Written by asterix98

January 1, 2011 at 6:26 am

Posted in Brain, google

Google and the brain

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Google’s page ranking algorithm solves two fundamental issues in search: how to represent the universe of web pages to yield meaningful search results, and equally important, how to rapidly retrieve this information in response to a query.

Google achieves the first by assigning a number (importance) to each page based on the number of incoming and outgoing links. Each of these incoming and outgoing links are assigned “weights”. However, this number is also modulated by the salience of the linking pages.  The importance of each page can then be represented as a simple summation of all pages linking to it (including itself). Each summation term is the product of the link weights and the importance of each page.

A column vector, constituting the universe of all web pages, can be now be derived, as the product of a giant NxN matrix, representing the weights of all links to every page, and the column vector itself. This giant matrix, then captures, all of the relationships, amongst the universe of web pages.

In the general case, the above discussion has to be expanded to a multi-dimensional space. Rapid retrieval, in this high dimensional space, requires other mathematical techniques such as finding a projection that will reduce the dimensionality of this space while still retaining the interrelationships. This is important to retain accuracy in the retrieved results.

A key idea embedded in this formulation is that representation and retrieval are not separate mechanisms but fundamentally intertwined processes that have much in common.

For mathematical convenience, as well as to handle corner cases, there are numerous modifications to this fundamental formulation. But they are not completely germane to the current discussion so we can ignore them for now.

It turns out that evolution needed to solve the same fundamental issues – representation and retrieval- to facilitate the rich panoply of cognitive processes evident in our brain. If we recast this as a search problem, the mathematics behind Google’s page ranking algorithm, seems to offer a simple and elegant solution to the problem.  

In brain science, numerous theories have been put forth, addressing these issues, but fall short mechanistically.  We can think of the universe of neurons akin to the universe of web pages. Neurons have incoming and outgoing links (remarkably dense).  Importance of each neuron then is a function of its “tuning/content” (things it responds to in the environment) and “context” (incoming/outgoing links). The “search terms” are derived from the statistics of the impinging stimuli (which has the benefit of gravitating towards solutions that naturally preserve salient features thereby reducing dimensional complexity). A second mechanism, for reducing the dimensionality of the external environment, can potentially be achieved through a divide and conquer strategy. In other words, the brain uses modularity.  Pruning (strengthening/weakening) of links is accomplished by mechanisms such as Hebbian learning/temporal synchrony/ correlated firing. Such a distributed representation, also allows for graceful degradation, in case of damage to portions of the neural machinery. Simply put, our brain is a giant matrix!!

Written by asterix98

December 8, 2010 at 7:03 am

Posted in Brain, google

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