Sunday, April 08, 2007

Psychology links

Can neuroscience make psychology redundant -- or, irrelevant? Greta and Dave Munger -- the bloggers behind the Coginitive Daily -- answer this question:

... With the help of neuroscience, so many advances have been made in understanding the human brain that it's indeed tempting to argue that psychologists aren't needed at all.

Yet human behavior itself is so complex that trying to understand it from an anatomical perspective alone simply doesn't make sense. You wouldn't try to learn how use a complicated computer program like Adobe Photoshop by taking the computer apart, or even by analyzing the lines of its computer code. [...]

Over at The Frontal Cortex, Jonah Lehrer comments:

The mind is the brain. Furthermore, we don't experience this distinction. We don't parcel our mental contents into "software" or "hardware," or perceive any separation between our behavior and our brain. Our psychological experience is unitary, and so should any science trying to describe our psychological experience. The fact that we still find it necessary to divide our mental sciences into different categories should remind us how much we have left to learn.

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Cosma Shalizi points us to a study that found one way of messing up our minds from outside:

Decisions require careful weighing of the risks and benefits associated with a choice. Some people need to be offered large rewards to balance even minimal risks, whereas others take great risks in the hope for an only minimal benefit. We show here that risk-taking is a modifiable behavior that depends on right hemisphere prefrontal activity. We used low-frequency, repetitive transcranial magnetic stimulation to transiently disrupt left or right dorsolateral prefrontal cortex (DLPFC) function before applying a well known gambling paradigm that provides a measure of decision-making under risk. Individuals displayed significantly riskier decision-making after disruption of the right, but not the left, DLPFC. ...

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New Scientist has a story on behavioral addictions (internet surfing, sex, gambling, etc. -- and perhaps blogging too!) whose signatures are not all that different from addiction to chemicals (drugs, coffee, nicotine ...) [via The Situationist]:

The evidence that behavioural addictions are very similar to chemical ones is mounting from brain studies too. According to addiction specialist Eric Nestler of the University of Texas Southwestern Medical Center in Dallas, drug addictions and "natural" addictions seem to involve shared pathways in the brain. "Take a person with sex addiction, or a pathological gambler: their brains all show abnormal responses - the same reactions to drugs of abuse," he says. [...]

GrĂ¼sser-Sinopoli and her colleague Ralf Thalemann found that gamers or gamblers experienced cravings, triggered by images from their favourite games, that were comparable to the responses of drug addicts. They had heightened physiological and EEG brain responses to the images, indicating that they were more pleasing and motivationally relevant than they were to inexperienced players. An addict's brain learns to respond much more dramatically to previously innocuous scenes, says GrĂ¼sser-Sinopoli.

They have conducted the same tests in cannabis, heroin and alcohol addicts, casino employees, abstinent gamblers and people undergoing methadone and naltrexone treatment. They found that this EEG response shows up in all addicts, but not in people who are exposed to the same surroundings yet remain unaddicted, such as casino employees. "People may deny they have a craving, but when we expose them to these cues the system is still active," she says.