Some thoughts on brain imaging

Can Brain Scans See Depression? – New York Times

At first glance, this doesn’t seem like anything new (imaging-wise) to neuroscientists, but there are some interesting opinions in the article.

Interesting fact:

In a range of studies, researchers have found that people with schizophrenia suffer a progressive loss of their brain cells: a 20-year-old who develops the disorder, for example, might lose 5 percent to 10 percent of overall brain volume over the next decade, studies suggest.

And I like the way this guy thinks:

In an interview, Dr. Amen said that it was unconscionable that the profession of psychiatry was not making more use of brain scans. “Here we are, giving five or six different medications to children without even looking at the organ we’re changing,” he said.

But is this true?

“The thing for people to understand is that right now, the only thing imaging can tell you is whether you have a brain tumor,” or some other neurological damage, said Paul Root Wolpe, a professor of psychiatry and sociology at the University of Pennsylvania’s Center for Bioethics.

Does anyone know of any good work applying machine learning to doing discrimination of neural disease (like ADD, general depression, and anything that’s basically not a giant lesion/tumor) in imaging scans?

a Biologically-Inspired System for Real-time Object Recognition

I skimmed this paper very briefly and it looks cool. Of course, I’m not a computer vision expert so I can’t really tell how state-of-the-art the results are.

Murphy-Chutorian, E., Aboutalib, S., Triesch, J.(2005). Analysis of a Biologically-Inspired System for Real-time Object Recognition. Cognitive Science Online, 3.2, pp. 1-14.

“We present a biologically-inspired system for real-time, feed-forward object recognition in cluttered scenes. Our system utilizes a vocabulary of very sparse features that are shared between and within different object models. To detect objects in a novel scene, these features are located in the image, and each detected feature votes for all objects that are consistent with its presence. Due to the sharing of features between object models our approach is more scalable to large object databases than traditional methods. To demonstrate the utility of this approach, we train our system to recognize any of 50 objects in everyday cluttered scenes with substantial occlusion. Without further optimization we also demonstrate near-perfect recognition on a standard 3-D recognition problem. Our system has an interpretation as a sparsely connected feed-forward neural network, making it a viable model for fast, feed-forward object recognition in the primate visual system.”

Postdoc position: "Bayesian inference and neural dynamics"

Below please find an email I received. I removed email addresses from this post to prevent harvesting by spambots — so I guess you’ll have to find a way to contact them yourself if you want the job.

> Subject: Job Annoucement – Theoretical Neuroscience Group in Paris.
> Reply-To: Sophie Deneve
> Two postdoctoral research positions are available in the newly created
> Theoretical Neuroscience Group in Ecole Normale Sup?rieure Paris, for a
> project funded by a Marie Curie Team of Excellence grant.?
> The overall theme of the project is “Bayesian inference and neural
> dynamics”, and the research will involve building and analyzing
> probabilistic treatments of representation, inference and learning in
> biophysical models of cortical neuron and circuits. To do so we will
> integrate complementary computational neuroscience approaches. The first
> studies neurons and neural networks as biophysical entities. The second
> reinterpret cognitive and neural processes as bayesian computations.
> The faculty of this group includes Misha Tsodyks, Boris Gutkin, Sophie
> Deneve and Rava Da Silvera. It is part of the Department of Cognitive
> Science in Ecole Normale Sup?rieure, a unique institution regrouping
> major scientists in computational Neuroscience, Brain imaging,
> Psychology, Philosophy, and Mathematics. We are situated in central
> Paris, at a walking distance to top scientific research and educational
> institutions. We have numerous international collaborations with
> experimental groups, with the goal of understanding the neural basis of
> cognition.
> The positions are for two years duration, with attractive salaries,
> including mobility allowance if applicable.? Generous travel support will
> be provided. Candidates should have
> 1- A strong mathematical/biophysical background and a strong interest in
> neuroscience, or
> 2- A strong neuroscience background and good basis in math and/or
> biophysics.?
> 3- Demonstrable interest in experimental collaborations.
> 4- Good communication skills.
> Candidates should send a CV, a 1 page research project and the address
> of two referees, to __email omitted__, before the 1st of
> November, 2005. For further information please contact Sophie Deneve (___email omitted___)
> or Boris Gutkin (___email omitted___) .

Recipe: ES cells to pure NS cells

In the August PLoS Biology, there is an article showing the production of pure neural stem cells from human embryonic stem cells.

The procedure is quite simple: Add growth factors FGF-2 and EGF to the ES cells and you get pure NS cells, which overcomes several of the limitations of previous neurosphere-based assays [Nature Methods].

Wild gorillas using sticks for measuring water depth and as walking stick

“We’ve been observing gorillas for 10 years here, and we have two cases of them using detached objects as tools,” said Thomas Breuer, from the Wildlife Conservation Society (WCS), who heads the study team in NouabalĂ©-Ndoki National Park in the Democratic Republic of Congo.

“In the first case, we had a female crossing a pool; and this female has crossed this pool by using a detached stick and testing the water depth, and trying to use it as a walking stick,” he told the BBC.

The second case saw another female gorilla pick up the trunk of a dead shrub and use it to lean on while dredging for food in a swamp.

She then placed the trunk down on the swampy ground and used it as a bridge.

BBC article