cognitive neuroscience
developingintelligence | December 28, 2006"Working memory" refers to the cognitive processes involved in temporarily storing & manipulating information. Unsurprisingly, this capacity is correlated with many measures of intelligence, but (somewhat more surprisingly) is also impaired in a variety of neurological disorders, including schizophrenia.
In a recent Psychopharmacology article, Deanna Barch reviewed studies demonstrating drug-induced improvements in working memory with a focus on possible applications for future schizophrenia treatments. What follows is a summary of this excellent article.
To a large extent, the effects…
mixingmemory | November 22, 2006We all know that there are gender differences in neuroanatomy, as well as in some cognitive tasks (females tend to do better on memory and verbal tasks, men on spatial tasks) and both cognitive and emotional development, though it's not clear how the cognitive/behavioral/developmental differences relate to the differences in neuroanatomy. Research on gender differences is often plagued by confounding variables such as sociological factors that are damn near impossible to control for. Jumping into the gender-differences game takes a lot of guts, or extreme naivete, then, because not only is…
mixingmemory | November 5, 2006Over at The Neurocritic, there's a great post on an imaging study that contrasted singing and speaking in tongues in five religious women. That reminded me of a paper I had read a couple months ago by one of the authors of the speaking in tongues study. It's a paper on the neuroscientific study of religion, but it primarily focuses on methodological issues (operational definitions of religion, subject selection, imaging techniques, etc.), so it may not be interesting to everyone. If you want to read it, you can do so here. Anyway, the reason I bring this stuff up (other than to link to the…
mixingmemory | November 3, 2006Well, not exactly, but I'll get to that in a minute. I read this paper last night, and afterwards, when I was looking around one of the author's pages, I came across a neuroimaging study designed to look for "pre-existing neural, cognitive, or motoric markers for musical ability" 1. Apparently there are neural differences between adult musicians and adult nonmusicians (duh), so the authors of the study wanted to see if these might be innate or the product of musical training. In the study, Norton et al. subjected 39 five to seven-year olds who were beginning piano or violin lessons, and 31…
mixingmemory | October 29, 2006One of the things that I love the most about cognitive science is that it's always challenging our intuitions about the world and how we perceive it. Think, for example, of all the classic Gestalt illusions, such as my all time favorite, the Kanizsa Triangle. What these illusions, and many other findings over the history of the study of visual perception show is that perception doesn't simply represent the world "as it is." Instead, perception is a fundamentally creative process, relying on inference, subtraction, and all sorts of other alterations of incoming sensory data. Spend a little…
mixingmemory | October 25, 2006Everyone's heard that losing a particular sensory modality causes the sensitivity of the other modalities to be heightened. Blind people are supposed to hear and smell really, really well, for example. While this is something that's been talked about for ages, there are actual neuroscinetific reasons for thinking that it might be true. When an area of the brain that is designed for one function or set of functions goes unused, or is underused, that area can be co-opted by other functions. But testing to see whether people with sensory deficits (blindness, deafness, etc.) actually have…
mixingmemory | September 30, 2006One of the top ten coolest experiments ever has to be Botvinick and Cohen's "rubber hand" experiment1. I'm going to let them describe the manipulation:
Each of ten subjects was seated with their left arm resting upon a small table. A standing screen was positioned beside the arm to hide it from the subject's view and a life-sized rubber model of a left hand and arm was placed on the table directly in front of the subject. The subject sat with eyes fixed on the artificial hand while we used two small paintbrushes to stroke the rubber hand and the subject's hidden hand, synchronising the…
mixingmemory | September 29, 2006The last couple weeks have seen a flurry of papers on mirror neurons, with three in last week's issue of Current Biology, and the paper on mirror neurons and sexual orientation in press at NeuroImage (is it just me, or will that journal publish anything?) that is fast becoming infamous (see posts on it by the Neurocritic, at the new cognitive anthropology blog Alpha Psy, and at ScienceBlog's own Frontal Cortex). So, I'm declaring this the weekend of mirror neurons. I should have the first post up sometime tomorrow.
Oh, and if you want more pornographic neuroscience, check out this old post.
mixingmemory | July 23, 2006There are a few topics in cognitive science that are like fingernails on a chalkboard to me. I find the very mention of them irritating, and the irritation can stick in my craw for days. At or near the top of that list are mirror neurons. These little cells have been made so sexy, either by their sheer coolness or massive, overblown publicity (it's hard to tell which), that they seem to have become the solution to virtually every problem in the study of cognition and behavior in the minds of some researchers. Of course, the blogosphere has also jumped on the mirror neuron boat (I was…
mixingmemory | July 19, 2006[First published on 2/4/05 at the old blog.]
If you've read my two previous posts on Ramachandran's principles of art (here and here), you've probably got a good idea of what Ramachandran's concept of beauty is. While his 10 principles of art are concerned more with the production of art and the visual principles that apply to the viewing of art, and he therefore does not discuss beauty at length, there does seem to be a fairly clear conception of beauty contained within his explanation of the principles and why they work in art. Specifically, beauty is seen as the product of perceiving…
mixingmemory | July 17, 2006[First published on 1/22/05 at the old blog.]
Recall V.S. Ramachandran's 10 principles of art.
Peak shift
Perceptual Grouping and Binding
Contrast
Isolation
Perceptual problem solving
Symmetry
Abhorrence of coincidence/generic viewpoint
Repetition, rhythm and orderliness
Balance
Metaphor
In the last post, I talked about the first three. In this post, I'll discuss 4, 5, 6, 7, and 10.
Isolation
Ramachandran's first three principles, peak shift, grouping, and contrast, may, after a little thought, seem fairly obvious. Art is generally not meant to be strictly representational, but instead to…
mixingmemory | July 15, 2006[First published on 1/20/05 at the old blog.]
As a starting point for the attempt to discover universals in art based on our knowledge of neuroscience, and visual neuroscience in particular, V.S. Ramachandran has proposed ten principles of art (eight of which come from the paper he wrote with William Hirstein, titled "The Science of Art") . The principles, in the order that Ramachandran discusses them, are:
Peak shift
Perceptual Grouping and Binding
Contrast
Isolation
Perceptual problem solving
Symmetry
Abhorrence of coincidence/generic viewpoint
Repetition, rhythm and orderliness
Balance…
mixingmemory | July 13, 2006[First posted on 1/20/05 at the old blog]
With all the controversy surrounding the issues in my last few posts, I thought it would be refreshing to talk about something completely uncontroversial: the existence of universals in art based on neurological mechanisms. (That was a joke, people). I've been doing some research on the cognitive science of art and aesthetics for my own work, and have wanted to post on it for a while, but there's a lot to talk about, and I haven't really been able to develop a plan for how to discuss it in this forum. So, I've decided to do what I usually do with blog…
mixingmemory | July 11, 2006Theory of mind, or how we think about what's going on in other people's heads, continues to be one of the hottest topics in cognitive science today. A debate continues to rage over whether we reason about other people's thoughts by means of theory-like propositional knowledge, or through simulation (i.e., putting yourself in their shoes... in your head). Since psychologists are unlikely to solve this debate by themselves, they've called in the artillery - cognitive neuroscientists. And those buggers have come up with some interesting ways to figure out where mentalizing (another name for…
mixingmemory | July 3, 2006Back in May, a study by Mitchell, Macrae, and Banaji (of Implicit Association Test fame) was published in Neuron that made the following claim (from the abstract):
We observed a double dissociation such that mentalizing about a similar other engaged a region of ventral mPFC linked to self-referential thought, whereas mentalizing about a dissimilar other engaged a more dorsal subregion of mPFC. The overlap between judgments of self and similar others suggests the plausibility of "'simulation'' accounts of social cognition, which posit that perceivers can use knowledge about themselves to infer…
mixingmemory | June 27, 2006Dave over at Cognitive Daily beat me to this (curse you, Dave!), but I wanted to point everyone to an article in Seed Magazine by Paul Bloom, titled "Seduced by the Flickering Lights of the Brain." If you can't tell from the title, the article is on the lure of imaging studies, and the sense that many have that simply taking a picture of the brain makes any experiment more scientific. (The title reminded me, specifically, of one reporter looking at pretty colored brain scan pictures and noting that the people in the study "didn't even fire up the thinking parts of their brains.")
If you've…
mixingmemory | June 27, 2006In the past, I've often wondered how journalists pick which studies to write about. The obvious answer is that they pick studies that will get readers or viewers, but given how little their stories correspond with the research they're writing about, it seems to me like they could pick any study and make it sellable. So the question remains, how do they pick the studies they write about? I read an article this weekend that provides an answer: they write about a study when they can get the author to say stupid shit. But before I get to the article, let me tell you a little bit about the study…
mixingmemory | June 18, 2006In yesterday's post on afterimages and aftereffects, I mentioned that demonstrations of neural adaptation for a particular feature (in the post, I used the examples of color and motion) is generally taken as evidence of the existence of specific neurons or groups of neurons that detect/process that feature. With motion or color, which are very basic features of the visual environment, this isn't very surprising, but in this post, I'm going to talk about some recent research demonstrating neural adaptation for a much more complex and surprising feature. But first, a little background on…
mixingmemory | June 10, 2006Anyone who's ever taken a bite of a Reese's Peanut butter Eggs that are only sold during the Easter season knows that chocolate is a mood enhancer, but in case you thought it might just be the wonderful taste, there is actual empirical evidence that chocolate can elevate your mood. Specifically, eating chocolate appears to make individuals suffering from atypical depression and seasonal affective disorder (SAD) feel better. As a result, chocolate and carbohydrate cravings are common in atypical depression and SAD, perhaps as a form of self-medication1. Several hypotheses have been offered to…