Tag Archives: psychology

How Prozac Sent Science Inquiry Off Track

I post often on examples of scientific inquiry in action. I think it is an important way to see how science works while searching for answers. The process is not a simple one, but after a solution is found it can often be presented as obvious. But while trying to find answers it is quite difficult.

How Prozac sent the science of depression in the wrong direction

But the success of Prozac hasn’t simply transformed the treatment of depression: it has also transformed the science of depression. For decades, researchers struggled to identify the underlying cause of depression, and patients were forced to endure a series of ineffective treatments. But then came Prozac. Like many other antidepressants, Prozac increases the brain’s supply of serotonin, a neurotransmitter. The drug’s effectiveness inspired an elegant theory, known as the chemical hypothesis: Sadness is simply a lack of chemical happiness. The little blue pills cheer us up because they give the brain what it has been missing.

There’s only one problem with this theory of depression: it’s almost certainly wrong, or at the very least woefully incomplete. Experiments have since shown that lowering people’s serotonin levels does not make them depressed, nor does it does not make them depressed, nor does it worsen their symptoms if they are already depressed.
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In this sense, Prozac is simply a bottled version of other activities that have a similar effect, such as physical exercise.
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It is jarring to think of depression in terms of atrophied brain cells, rather than an altered emotional state. It is called “depression,” after all. Yet these scientists argue that the name conceals the fundamental nature of the illness, in which the building blocks of the brain – neurons – start to crumble. This leads, over time, to the shrinking of certain brain structures, like the hippocampus, which the brain needs to function normally.

Placebo Effect

Don’t laugh, sugar pills are the future

In fact the new study added nothing (and it was ridiculously badly reported): we already knew that antidepressants perform only marginally better than placebo, and the National Institute for Health and Clinical Excellence (Nice) guidelines has actively advised against using them in milder depression since 2004. But the more interesting questions are around placebo.
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Another study from 2002 looked at 75 trials of antidepressants over the past 20 years, but looked only at the response in the placebo arms of the trials, and found that the response to placebo has increased significantly in recent years (as has the response to medication): perhaps our expectations of those drugs have increased, or perhaps, conversely to our earlier example, the trial designs have become systematically more flattering. I’m giving you tenuous data, on an interesting area, because I know you’re adult enough to cope with ambiguity.

Scientists Reconsider Autism

Webcast – In My Language – about what gets considered thought, intelligence, personhood, language, and communication, and what does not.

Scientists Reconsider What They Think They Know

This movement is being fueled by a small but growing cadre of neuropsychological researchers who are taking a fresh look at the nature of autism itself. The condition, they say, shouldn’t be thought of as a disease to be eradicated. It may be that the autistic brain is not defective but simply different — an example of the variety of human development. These researchers assert that the focus on finding a cure for autism — the disease model — has kept science from asking fundamental questions about how autistic brains function.

A cornerstone of this new approach — call it the difference model — is that past research about autistic intelligence is flawed, perhaps catastrophically so, because the instruments used to measure intelligence are bogus. “If Amanda Baggs had walked into my clinic five years ago,” says Massachusetts General Hospital neuroscientist Thomas Zeffiro, one of the leading proponents of the difference model, “I would have said she was a low-functioning autistic with significant cognitive impairment. And I would have been totally wrong.”
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And that hurts autistic people, Dawson says. She makes a comparison with blindness. Of course blind people have a disability and need special accommodation. But you wouldn’t give a blind person a test heavily dependent on vision and interpret their poor score as an accurate measure of intelligence. Mottron is unequivocal: Because of recent research, especially the Raven paper, it’s clearer than ever that so-called low-functioning people like Amanda Baggs are more intelligent than once presumed.The Dawson paper was hardly conclusive, but it generated buzz among scientists and the media. Mottron’s team is now collaborating with Massachusetts General Hospital’s Zeffiro, a neuroimaging expert, to dig deeper.

Continue reading →

Electrical Brain Stimulation Boosts Memory

Deep stimulation ‘boosts memory’

The technique involves implanting electrodes into the brain: in this case into an area in the limbic system called the hypothalamus, which is thought to control the appetite. When the electrodes were stimulated by electrical impulses the patient began to experience feelings of deja vu.

He then had a sudden perception of being in a park with friends. He felt younger, thought he was around 20-years-old, and his girlfriend of the time was there. He was an observer, and saw the scene in colour. As the intensity of the stimulation increased, details in the scene became more vivid.
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The results suggest it might be possible to use deep brain stimulation directly to boost memory. “We hopefully have found a circuit in the brain which can be modulated by stimulation, and which might provide benefit to patients with memory disorders,” said Professor Lozano. He is now leading a pilot study into whether deep brain stimulation can help people with early Alzheimer’s disease. They are initially testing six patients.

The Science of Kissing

The Differences in Gender — Sealed With a Kiss

In people, kissing to express affection is almost universal. About 90 percent of human cultures do it. One traditional view is that kissing, known scientifically as osculation, evolved from women chewing food for their children and giving it to them mouth-to-mouth, Fisher said.

But, she said, “I’ve never believed that,” adding that similar behavior is found in many species. Birds tap beaks. Elephants shove their trunks in each other’s mouths. Primates called bonobos practice their own version of French kissing. Fisher believes kissing is all about choosing the right mate.

“There’s so much information exchanged when you kiss someone that I just thought it must play a vital role in mate choice, and this paper is elegantly showing that,” Fisher said. A disproportionate amount of the brain, she noted, is geared toward interpreting signals from the mouth.

The research paper – Sex Differences in Romantic Kissing Among College Students: An Evolutionary Perspective

The Decoy Effect

The Decoy Effect, or How to Win an Election

The human brain, however, always seeks simple answers. Enter the third candidate. Huber told some people there was also a choice of a four-star restaurant that was farther away than the five-star option. People now gravitated toward the five-star choice, since it was better and closer than the third candidate. (The three-star restaurant was closer, but not as good as the new candidate.)

Another group was given a different third candidate, a two-star restaurant halfway between the first two. Many people now chose the three-star restaurant, because it beat the new option on convenience and quality. (The five-star restaurant outdid this third candidate on only one measure, quality.)

What the decoy effect basically shows is that when people cannot decide between two front-runners, they use the third candidate as a sort of measuring stick. If one front-runner looks much better than the third candidate, people gravitate toward that front-runner. Third candidates, in other words, can make a complicated decision feel simple.

Brain Development

Making the Mind, Why we’ve misunderstood the nature-nuture debate by Gary Marcus

The mapping between genes and behavior is made even more complex by the fact that few if any neural circuits operate entirely autonomously. Except perhaps in the case of reflexes, most behaviors are the product of multiple interacting systems. In a complex animal like a mammal or a bird, virtually every action depends on a coming together of systems for perception, attention, motivation, and so forth. Whether or not a pigeon pecks a lever to get a pellet depends on whether it is hungry, whether it is tired, whether there is anything else more interesting around, and so forth. Furthermore, even within a single system, genes rarely participate directly “on-line,” in part because they are just too slow. Genes do seem to play an active, major role in “off-line” processing, such as consolidation of long-term memory—which can even happen during sleep—but when it comes to rapid on-line decision-making, genes, which work on a time scale of seconds or minutes, turn over the reins to neurons, which act on a scale of hundredths of a second. The chief contribution of genes comes in advance, in laying down and adjusting neural circuitry, not in the moment-by-moment running of the nervous system. Genes build neural structures—not behavior.

An interesting read on brain development. This is another topic I find very interesting.