VS Ramachandran's TED Talk

Although I’ve been a longtime fan of Ramachandran’s excellent book Phantoms in the Brain, this TED talk is like a compressed summary of the highlight’s of his research. He’s a great speaker and he covers in 20 minutes my two favorite examples in the book (Capgras delusion and mirror treatment for phantom limb syndrome). Perhaps the best part of the talk is that, after listening to it, I was convinced more than ever before of the statistical nature of sensory perception (ie. the brain attempts to find the most likely explanation for sensory observations) and the integrative nature of central processing of multiple modalities. 


Atul Gawande also recently wrote a New Yorker article about treating phantom itch with Ramachandran’s mirror box. I found this part of Gawande’s article on statistical inference in perception most interesting:

You can get a sense of this from brain-anatomy studies. If visual sensations were primarily received rather than constructed by the brain, you’d expect that most of the fibres going to the brain’s primary visual cortex would come from the retina. Instead, scientists have found that only twenty per cent do; eighty per cent come downward from regions of the brain governing functions like memory. Richard Gregory, a prominent British neuropsychologist, estimates that visual perception is more than ninety per cent memory and less than ten per cent sensory nerve signals. When Oaklander theorized that M.’s itch was endogenous, rather than generated by peripheral nerve signals, she was onto something important.

I’m not familiar with this field but I wonder if anyone has tried to quantify what percent of our conscious experience that we normally believe to be 100% due to sensory input is actually recall from memory/inference based on past observation. Also, can this percentage adaptively change? Perhaps there are situations where the brain chooses to rely more heavily on memory and other cases where it relies more on primary sensory input.

Varmus on the Daily Show

Just heard about this nice interview from Monday night of Obama science advisor (and former NIH head and Nobel laureate) Harold Varmus with some details on what went wrong over the last few years:

Best line from Jon:

Does 8 years in the wilderness do real damage to science? You think about the Middle Ages.

Another interesting exchange, where Jon asks about skills needed to be a successful scientist:

Jon: I’ve never met a man of your stature as a scientist so well-versed in the bureacratic process. Is that part of being a scientist now? Do you have to also know how to navigate those waters?

Varmus: Look, I went to Washington as someone who had been a lab rat for 25 years […] and suddenly I had to run a big agency. You learn it. It’s like anything else.

Nature: It's good to blog

From the department of self-affirming citations, Nature has an article this past week titled It’s good to blog on the importance of blogging as a way of conversing directly with paper authors. Perhaps most relevant is this:

Indeed, researchers would do well to blog more than they do. The experience of journals such as Cell and PLoS ONE, which allow people to comment on papers online, suggests that researchers are very reluctant to engage in such forums. But the blogosphere tends to be less inhibited, and technical discussions there seem likely to increase.

Moreover, there are societal debates that have much to gain from the uncensored voices of researchers. A good blogging website consumes much of the spare time of the one or several fully committed scientists that write and moderate it. But it can make a difference to the quality and integrity of public discussion.

Ethics and drug companies at HMS

Harvard Medical School in Ethics Quandary [NYT]

Apparently, Harvard gets one of the worst grades among med schools for mixing drug company money with research with very little regulation:

BOSTON — In a first-year pharmacology class at Harvard Medical School, Matt Zerden grew wary as the professor promoted the benefits of cholesterol drugs and seemed to belittle a student who asked about side effects.

Mr. Zerden later discovered something by searching online that he began sharing with his classmates. The professor was not only a full-time member of the Harvard Medical faculty, but a paid consultant to 10 drug companies, including five makers of cholesterol treatments.

“I felt really violated,” Mr. Zerden, now a fourth-year student, recently recalled. “Here we have 160 open minds trying to learn the basics in a protected space, and the information he was giving wasn’t as pure as I think it should be.”

Mr. Zerden’s minor stir four years ago has lately grown into a full-blown movement by more than 200 Harvard Medical School students and sympathetic faculty, intent on exposing and curtailing the industry influence in their classrooms and laboratories, as well as in Harvard’s 17 affiliated teaching hospitals and institutes.

UPDATE: The NYT is reporting that at US Senator Chuck Grassley has asked Pfizer to provide details of its payments to 149 HMS faculty members (a frankly astonishing number) and for more information about a Pfizer employee taking pictures at a demonstration by med students against corporate influences at HMS.

Theory rising

Although it’s a few months old, Larry Abbott has an excellent article in Neuron on the recent (last 20 years) contributions of theoretical neuroscience. (He came by MIT last week to give a talk and that’s when I found out about the article.) It’s a review that is not too long and provides a good overview with both sufficient (though not overwhelming) detail and original perspective. It’s rare to find a short piece that is so informative. (And for a more experimentally-oriented review with an eye toward the future, see Rafael Yuste’s take on the grand challenges.)

Click on for some of my favorite passages from the Abbott piece. Continue reading