Tuesday, May 27, 2008

Encephalon - 46th Edition



Welcome to the Forty-Sixth Edition of Encephalon, a neuroscience blog carnival.

Dave and Greta Munger of Cognitive Daily just attended the 20th Annual Convention of the Association for Psychological Science in Chicago, and their live reports are hot off the internet. Read about The persistence of racism even among the well-intentioned and Doing algebra -- it's the little things that count.

Also on the educational front, Kylie from PodBlack Blog brings us Girls Got What? Competitions, Science Careers and Benefits, an investigation into whether it's really just brains or really just well-established strategy.

From Chris at Developing Intelligence, we can learn about Impulsivity Due to Distortions in Time: Hyperbolic Discounting and Logarithmic Time Perception. What is hyperbolic discounting? Wikipedia tell us:
In behavioral economics, hyperbolic discounting refers to the empirical finding that people generally prefer smaller, sooner payoffs to larger, later payoffs when the smaller payoffs would be imminent; but when the same payoffs are distant in time, people tend to prefer the larger, even though the time lag from the smaller to the larger would be the same as before.
Typically, cognitive control functions are thought to be a key factor in the ability to delay for a larger payoff. But there's an alternative, as Chris explains:
...if time is not represented linearly by the mind, perhaps it is that peculiarity which generates impulsivity, rather than a failure of control! ..... [Zauberman et al.'s] forthcoming paper in the Journal of Marketing Research demonstrates conclusively that the hyperbolic function that characterizes discounting rate does indeed reflect nonlinearities in time perception.
Attention-deficit hyperactivity disorder is (of course) associated with impulsivity...could there be an element of exaggerated time distortion in their hyperbolic discounting functions? What a wacky idea!

Alvaro, our Encephalon host at Sharp Brains, brings us a more tested idea, Mindfulness Meditation for Adults & Teens with ADHD (by guest blogger Dr. David Rabiner). Mindfulness has been shown (by Davidson and his colleagues, among others) to improve attentional focus and to decrease emotional reactivity.

Buddha brain image from Ellerman.info

The Neurocritic has a past post, Present Tense, that reviews the literature on neuroimaging studies of mindfulness-based meditation.

Speaking of a practice associated with Buddhism, Daniel at Neuroanthropology enters the fray engendered by a recent op-ed piece in the New York Times (by columnist David Brooks) in The Neural Buddhists of David Brooks. Daniel is sympathetic to much of his viewpoint (against hard-wired morality, for instance), but for hard-core materialists, Brooks' most troubling comment is
Over the past several years, the momentum has shifted away from hard-core materialism.
Next, Vaughan from Mind Hacks writes about the rare phenomenon of 'supernumerary phantom limbs' in Phantom extra limbs. A recent paper in Neurology reported on two case studies following hemorrhage in the pons, part of the brain stem:

Both patients had the experience of having a third arm and a third leg... One distressing element for the female patient was that although the patient could 'move' the phantom arm voluntarily, "she described occasional loss of control and feeling strangulated by the phantom arm around the neck".

Speaking of arms, Sandra from Channel N is very excited to present
a video aboot the neuroArm, a robotic system that enables a surgeon to perform remote haptic-assisted neurological microsurgery using real-time MRI. One of the most advanced robots in existence, it's a very exciting Canadian achievement.

The first-ever surgery was successfully performed by Dr. Garnette Sutherland at the University of Calgary on May 12, 2008.
Neuroscientifically Challenged explains The Neuroscience of Distributive Justice. What is distributive justice, you might ask?
...how goods and benefits should be dispersed throughout a society in a fair and just manner. As an extreme example of this dilemma, imagine you are commissioned to deliver 100 lbs. of food to a famine-stricken region that consists of two villages a hundred miles apart. If you deliver half of the food to the first village, then travel to the second, 30 lbs. of the food will spoil during the trip...

Philosophers have offered several solutions to debates of this nature. Utilitarianism... asserts that one’s primary goal should be the achievement of a maximal amount of good or happiness. In the situation described above, a utilitarian might opt to deliver all of the food to the first village. ..... Another approach to such a quandary is known as deontological ethics, which emphasizes not the consequences of one’s actions, but whether the actions are right or wrong, just or unjust. From a deontological perspective, it would be unjust to distribute the food unequally.
To examine the trade-off between equity and efficiency, Hsu et al. (2008) devised a task in which the participants decided on how to allocate money to children living in an orphanage in northern Uganda. You can see an example of an experimental trial in this must-see movie from the paper's Supporting Online Material (embedded below).



Movie s2
No Switch Trial. Illustration of a trial where the subject does not switch the lever. Animation speed is increased for illustration purposes. See Fig. 1 for actual duration of events and screens.

You can bet that The Neurocritic will have something to say about this study in the near future...

Neuroscientifically Challenged also poses the question, Would You Vaccinate Your Kids Against Drugs?

Next up are Brain Games or Drugs for Cognitive Enhancement, written by Sharp Brains guest columnist Pascale Michelon, Ph.D. She discusses the exciting recent finding by Jaeggi et al. (2008): Improving Fluid Intelligence With Training on Working Memory. It's a growing field. For more about working memory, be sure to read Developing Intelligence on The Digital Resolution of the Mind: Discrete Precision in Working Memory.

Jake from Pure Pedantry has submitted a very sad but informative post, Sen. Kennedy and Glioma, which deals with Senator Ted Kennedy's brain cancer, treatment, and prognosis. The majority of these malignant brain tumors are generally fatal. Sen. Kennedy has been a leading proponent of mental health parity, the proposal that insurance companies cover mental disorders and other medical ("physical") disorders in an equivalent manner.

Speaking of which, Dr. Shock writes a critical piece about the pitfalls of supportive psychotherapy in Supportive Psychotherapy mostly Novice Pilots Flying In The Dark Without Maps. Meanwhile, Dr. Deb looks at recent neurobiological research linking burning incense and possible new antidepressant medications in Smell is Swell. A brand new class of depression and anxiety drugs might be right under our noses! Hippies might have something going with that incense crap!

PodBlack Blog asks us to Chalk It Up To Forensic Science and watch
a lecture presentation at a local Science Education centre that provides not only insights to the minds behind crime-solving but how the public perception mind the messages on TV.
Finally, in My Mascot Only Gave Me Sex Appeal, Kylie tells us that
it may seem strange that the Chinese are willing to blame toys for recent disasters but no weirder than other superstitions that work in people's favour.
Why, that's no stranger than reference to a scary bunny furry wearing a gigantic clock in The Neurocritic's post about why You're My Favorite Person... (which is really about how watching movie clips with your favorite actress can boost your peripheral levels of dopamine and circulating natural killer cells, and activate your medial prefrontal cortex, thalamus, hypothalamus, subcallosal gyrus, posterior cingulate cortex, superior temporal gyrus, and cerebellum).

ADDENDUM: A late-breaking submission from Mo at Neurophilosophy covers the recent finding that a protein extracted from green algae can partially restore visual function: Channelrhodopsin restores vision in blind mice.

That's it for this edition. The next Encephalon will appear on June 9 at Channel N.

No comments:

Post a Comment