In her book Delusions of Gender (which I have not read though am intrigued to do so), cognitive neuroscientist Cordelia Fine places several modern studies of early differences in brain anatomy/function into a long line of sexist explanations for supposed differences in male and female behaviors.

The basic argument is that there has been no convincing connection made between any measured structural differences (which she argues might not exist) to behavioral differences. Just another case of correlation (maybe) and not causation.

Here’s a description of study that you might already be familiar with and Fine’s take on it:

Dr. Baron-Cohen’s lab conducted research on infants who averaged a day and a half old, before any unconscious parental gender priming. Jennifer Connellan, one of Dr. Baron-Cohen’s graduate students, who conducted the study, showed mobiles and then her own face to the infants. The results showed that among the newborns the boys tended to look longer at mobiles, the girls at faces.

Dr. Fine dismantles the study, citing, among other design flaws, the fact that Ms. Connellan knew the sex of some of the babies. Because it was her face they were looking at and she was holding up the mobile, Dr. Fine says, she may have “inadvertently moved the mobile more when she held it up for boys, or looked more directly, or with wider eyes, for the girls.”

Although I am unsure about the scientific merits, it is refreshing to see a new viewpoint in this debate. It provides some food for thought on this interesting topic:

Summarizing the research, she writes, “Nonexistent sex differences in language lateralization, mediated by nonexistent sex differences in corpus callosum structure, are widely believed to explain nonexistent sex differences in language skills.”

What all this adds up to, she says, is neurosexism. It’s all in the brain.

I think this chapter might be helpful for neuroscientists outside of the lab. Often a dinner table discussion has moved to the idea of “quantum consciousness” or “quantum free will”. Often, someone will mention Roger Penrose, who has become something of a poster boy for this idea that quantum indeterminacy (eg. Heisenberg’s uncertainty principle) is one possible way that free will is really free. And then, people look around and say, “Well, you’re a neuroscientist. Do we have free will?” (And that’s when I take another big drink or bite while I figure out something semi-coherent to say.)

Sompolinsky does a nice job of evaluating such claims (in the end, he says we cannot rule out the possibility that the brain is an indeterministic system but it seems unlikely) and provides nice scientific insight. In his view, it is far more likely that the brain’s apparent randomness (eg. individual cell spike rasters vary across repeated presentations of the same stimulus) is more simply explained by thermal noise (think of varying channel gating properties) and chaotic brain dynamics. (Recall, a chaotic system is still deterministic; it simply exhibits aperiodic behavior due to exquisite sensitivity to initial conditions. It is difficult to predict the long-term behavior of chaotic systems. The more we know the initial conditions in detail, the better our prediction.) On the other hand, he argues that the relevant length and time scales for neurons (micrometers and milliseconds) are far larger by many orders of magnitude than those of quantum noise. Chaos might amplify such quantum events, but this is far from being the simplest, most parsimonious explanation. Given the current level of neuroscience understanding, this is almost idle speculation. Regardless of the (in)determinacy of the world, Sompolinsky effectively argues against any non-physical, purely mental (ie. dualistic) agent of causation.

Thus, in sum, the world and our brains might not be determined but, even given that, there’s no reason to believe we have any causative ability to change things in the sense of traditional free will. These observations seem right on the mark to me. I hope they bring some insight for others. Or at least a way to fend off the dinner-table-free-will-conversation barrage of questions.

I saw this somewhat more favorable review a few weeks in the NYT and was intrigued by the book. As an undergrad, I majored in cognitive science and English and, naturally, was fascinated by the cultural differences of academics in these disparate fields.

As in the Salon article, I also think attempts to unify the “two cultures” (ie. arts and sciences) are misguided. A work like Lehrer’s book (which I have not read) will need to work hard to “prove” its thesis and likely sound very forced. What can we really say about arts vs. sciences? For that matter, is it important to make value judgments on this topic? I’d say, no. We seem to have a natural urge to categorize our activities and then try to order them. Science is more worthwhile. Art is a more creative endeavor. Are these blanket generalizations productive?

But there is overlap between the two cultures and those regions seem more and more important to me. And I think neuroscience in particular has a lot to say here, too. If we know what makes good art good (in a scientific way), will we stop appreciating it or enjoying it? (This is similar to the idea that if someone told you free will was simply an illusion would the illusion be any less powerful than it is right now?) Often, the surprise of creative thought underlies the best science and the best art. Okay, there’s my attempt at a unification!

On a separate note, there certainly seems to be a hunger amongst the reading public for neuroscience books, despite our incomplete picture of how the brain works. For those frustrated with slow progress in research, maybe we should just go write a book.

The concept that the brain holds maps of the surface of the body in the primary sensory and motor cortex is a fascinating but well known fact to the field of neuroscience since the early work of Wilder Penfield. What is less broadly appreciated is the concept of “peripersonal space”. A new book by Sandra and Matthew Blakeslee describes peripersonal space in the following way:

The maps that encode your physical body are connected directly, immediately, personally to a map of every point in that space and also map out your potential to perform actions in that space. Your self does not end where your flesh ends, but suffuses and blends with the world, including other beings. [...] Your brain also faithfully maps the space beyond your body when you enter it using tools. Take hold of a long stick and tap it on the ground. As far as your brain is concerned, your hand now extends to the tip of that stick. [...] Moreover, this annexed peripersonal space is not static, like an aura. It is elastic. [...] It morphs every time you put on or take off clothes, wear skis or scuba gear, or wield any tool. [...] When you eat with a knife and fork, your peripersonal space grows to envelop them. Brain cells that normally represent space no farther out than your fingertips expand their fields of awareness outward, along the length of each utensil, making them part of you.

What I appreciate about this, besides the stretchy comic book characters that it makes me think about, is that it provides a powerful perspective to begin piecing together a mass of disparate neuroscience data, which the Blakeslee’s capitalize on.

You’ll recognize the name Sandra Blakeslee from her co-authorship with Jeff Hawkins in On Intelligence and with V.S. Ramachandran in Phantoms in the Brain. This new book continues in the spirit of illustrating the broader significance of surprising findings in neuroscience. It covers a lot of recent neuroscience research, including mirror neurons, place cells and grid cells, the insular cortex and neuroprosthetics. For anyone looking to get the quick picture of these frontier research areas, this book serves as an excellent primer. It does an excellent job of making connections to socially relevant topics such as the secrets of athletic excellence, underlying causes of eating disorders and the modern obsession with plastic surgery. I have come to believe that neuroscience will eventually provide concrete explanations for the metaphors we use and the spooky phenomena we believe in but science cannot prove. Along those lines, this book does a great job of describing brain mechanisms that may underly paranormal phenomena like auras and out-of-body experiences.

One of my favorite parts is chapter six, a short chapter with a Phantoms in the Brain feel that presents some extremely jarring clinical examples of neurological problems potentially caused by body map disorders. It describes cases of individuals who want to have their limbs amputated because they feel like they don’t belong to them, individuals who no longer get feedback from their limbs as if they have disappeared, as well as cases of one woman who felt like she had three arms and three legs. That these cases exist are fascinating in their own regard; that there exists a systems-level conceptual framework with which we might understand the underlying causes for them is utterly incredible.

The implications of these ideas to AI are significant. What kinds of intelligent systems can we build by assuming that they have ego-centric representations of objects in their peripersonal space, or by assuming that their motor intentions are tickled by watching the movements of other creatures? The implications for computational neuroscience are also significant. What kind of system of neuronal processors is capable of producing cells that are sensitive to peripersonal space? What information must flow into those cells, and where is that information available from in the brain? Along what channels and using which “algorithms” does your brain map the visual information of a person moving their limbs to the motor areas that control your limbs? Perhaps I’ll be able to read about these things in the next Blakeslee neuroscience tour de force.

The Body Has a Mind of Its Own: How Body Maps in Your Brain Help You Do (Almost) Everything Better
by Sandra Blakeslee (Author), Matthew Blakeslee (Author)
Random House Publishing Group

(Full disclosure: Sandra Blakeslee and Random House kindly sent us a copy of the book to review before their release date…thanks guys!)

The first few paragraphs are some basic introductory comments about neuroscience, so start a bit down the page…

Full review is after the jump.

Moffett is a medical student who became interested in neuroscience through a neuroanatomy course she took at Stanford. For most people, an interest in neuroscience might spur further reading, contemplation of graduate school, etc. But Moffett decided to talk to several people (neuroscientists, neurosurgeons, and neuro patients) firsthand to satisfy her own neuroscience curiousities. This particular approach has its own strengths and weaknesses: namely, that the book necessarily follows Moffett’s path and her own interests. It is not particularly comprehensive about any one area (nor does that appear to be her intention) but it does a good job of chronicling her intellectual journey with the depth necessary to make it worth the effort of any reader, beginning or advanced. Importantly, it is not a content-poor survey of what’s new and cool in neuroscience. There seems to be a flood of this type of book recently and I am happy to say that Enigma is not to be counted amongst those works.

What makes the book worthwhile is that Moffett has had real, sincere conversations with people in the book and those conversations provide extra insight to the papers and experiments she explains. Her verbal snapshots are fascinating: How a fast-talking neurosurgeon’s day unfolds, undergoing a sleep research study on dreaming as a patient, conversing with different personalities of a dissociative identity disorder patient, and several others.

One of the most fascinating portions of the book details the time Moffett spent with Francis Crick and Christof Koch (in the few months right before Crick’s death). The casual dialogues between Crick and Koch as they hypothesize how the brain assembles information into conscious thought provide a unique viewpoint for Moffett’s nice presentation of their consciousness framework. In this section, she recounts an amusing conversation where Crick is harshly critical of his wife’s naive understanding of electricity and prods the readers to consider if perhaps Crick’s ideas on consciousness — an unabashedly difficult thing to study — might one day be regarded as similarly naive.

Moffett’s strength lies in her ability to not simply present the research as it is but to enhance understanding of the research through her dialogues with those involved in creating it. Anyone who has seen a good talk knows how much more valuable it can be than simply reading the paper, especially at providing context and insight into the researcher’s path of discovery. The same is true with Enigma . Perhaps it was the title more than anything else which shaped my initial, disdainful impression of the book as only one of the many popular, “gee-whiz-isn’t-the-brain-neat” group of recent books. But it is a well-researched work full of insightful conversations and I recommend it highly.

There’s a lot to say about Kurzweil”s new book, The Singularity is Near (book website; book on Amazon). This book is similar to his previous books (Age of Intelligent Machines, Age of Spiritual Machines) in style and research but the thesis here is that we are on the precipice of a major change in human civilization: We are soon going to create entities of superior intelligence in all aspects to our own selves. This is the Singularity.

Full book review after the jump

TSIN is based on the same fundamental idea that his previous books emphasize: The acceleration of the rate of innovation. Ray contends that the time between major milestones, specifically with respect to human-created computational ability, is getting faster and that most people don’t realize that this means the “future” will be here faster than one predict.

Unlike the previous books, Ray talks a lot more about biology in this work and, in particular, neuroscience. He sprinkles the book with quotes from well-known researchers talking about, well, stuff they normally don’t talk about like predictions about the future of neuroscience. (Early on, Kurzweil makes a smart remark about how scientists are trained to be very skeptical and pride themselves on underestimation of the impact of new technologies.)

Most of the neuroscience research is not terribly novel for those who regularly read journals or attend conferences, but that is not what you should be reading this book for. Ray, in the best traditions of the multidisciplinary “renaissance scientist” (perhaps an almost extinct species in these times of ultra-over-specialization), excels at assembling many disparate ideas from different disciplines together. That alone can be a recipe for disaster, but Ray does a nice job of combining ideas and technologies with his constant back of the envelope calculations to show the multiplicity of routes to his central thesis.

There are a few chapters specifically on neuroscience and there are some very nice insights in these chapters. A commendable discussion of levels of analysis in neural systems is presented and elaborates on the difficulties of doing simple estimates, based on number of neurons or synapses, of the computational power of the brain. Sure, the connections within a cortical region might be well understood but what about the local connections within a few hundred microns? Similarly, we might model a set of neurons and their connections but how about the extracellular diffusion of neuromodulators near that synapse or local electric fields or countless other influences? It was a nice surprise to see a relatively accessible book bringing up these issues, even if only briefly.

Ray also tackles the important divide of analytic versus neuromorphic methods in computational neuroscience, a question that I doubt many computational neuroscientists have given careful thought to. He sides with the neuromorphic approach and seems to suggest that studying the genetic basis of the brain might be more beneficial than studying the brain itself since the design of the brain and many essential features are captured by this compact representation.

This is not to say that the book is without flaws. There are many contentious ideas that ever-optimistic Ray (I think that’s a good thing, by the way) presents as fact: Reversible computing leads him to believe that eventually all computation will require no energy. Memory might be more than connection patterns and neurotransmitter concentrations, and I mean a lot more. And, as we’ve discussed here before, we are far away from any kind of neuromorphic hippocampus, despite what some may claim. Also, it’s hard to judge how seriously we’re supposed to take some of the time estimates, especially when there’s little justification for the particular date — sending nanobots through the bloodstream to monitor every neuron’s activity noninvasively by 2020? Maybe. (As Ray points out, “there are more than 50,000 neuroscientists in the world, writing articles for more than 300 journals.” Who knows…) Of course, the biggest one is the Singularity itself, which he pins at 2045 based on extrapolating computation per dollar trends. Maybe.

The book also includes several sections on computation and related application-oriented fields (nanotech, robots) that I’ll skip over but the best part of the book might be Ray’s answers to his critics. From the wacky (Penrose’s quantum mechanics in the neural cytoskeleton) to the deeply philosophical (Searle’s Chinese Room argument against strong AI), it is clear that he has thought about the viability of his ideas and is prepared to take on the obvious criticisms that others might lob at him.

I don’t think I would have gone to graduate school in neuroscience if I didn’t believe, like Ray, that the Singularity is near. Just how near, I’m, unfortunately, not sure.