YOU MAY NOT HAVE RHYTHM, BUT YOUR BRAIN DOES
New research begins to demystify communication between brain regions, potentially paving the way to treating disorders caused by crossed signals
A great set of studies by scientists I’ve corresponded with and respect. It’s all about rhythm.
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A blurb that’s just coming out into the press.
Slow wave activity (SWA), a stable trait dependent marker of the intensity of non-rapid eye movement (NREM) sleep, is lower in young healthy African-Americans compared to Caucasians who were matched for age, gender and body weight, according to recent research.
It would be interesting to see the full report on this, whether subjects were matched on social and economic scales, and whether other health issues played a factor.
Update: Apparently there was a big sleep convention lately. Here were some other findings:
Sleep restriction affects children’s speech
Electrical brain waves predict attentional deficits following sleep deprivation
Sleep disorders are highly prevalent among police officers
Sleep deprivation can lead to increased smoking and drinking
A small handful of researchers, and the FDA, are skeptical about prescribing selective serotonin reuptake inhibitors to children and teenagers. First, the point of view of the researchers.
Gingrich used mice that were genetically altered so that they lacked the ability to mop up serotonin. They were—in effect—born on Prozac. He wanted to see how depression was related to serotonin and norepinephrine, another neurotransmitter. “Our simple-minded idea was these mice would look like mice treated chronically with Prozac,” Gingrich says. They should have been free of anything like a mouse’s version of depression or anxiety.
Gingrich found quite the opposite. Because he could not chat with them about their feelings, he gave the mice stress tests. (An inability to handle stress is one hallmark of depression.) He put a small electric charge on the floor on one side of their cage. Normal mice will quickly learn to escape the tiny shock by running to the other side. These mice did not. “They have a tendency to freeze,” he says. “They stay on the same side where the foot shock is being administered, or they escape much more slowly.” The mice—despite having lived their entire lives as if they were on Prozac—were afflicted with what looked suspiciously like an anxiety disorder.
Now, fair and balanced, the psychiatrists…
Even in the face of this evidence, however, many psychiatrists believe that antidepressants do far more good than harm in children and teens. Like Emslie in Texas, Harold Koplewicz, a professor of psychiatry at New York University and one of the city’s top child psychiatrists, has been using SSRIs aggressively in children and teenagers for more than a decade. “I am probably the first person to give these meds to kids clinically,” he says. As recently as a few years ago, most psychiatrists thought they should try talk therapy with kids before giving them medication. But that has changed, he declares.
He has seen what happens to teenagers who are not treated. “After they’ve had one episode of depression, they’re 60 percent more likely to have another. If they have two, they’re 90 percent more likely to have a third. And subsequent episodes are more difficult to treat…. Every good clinician will tell you the risk of not taking the medication is greater” than the possible risks of taking SSRIs.
The inflammation hypothesis of Alzheimer’s, which suggests that inflammation in the brain triggers a cascade of cellular events that over time results in deposits and atrophy, and subsequent cognitive deficits, is still relatively controversial.
A Harvard researcher found a correlation between inflammation and future prevalence of Alzheimer’s.
The participants’ blood was tested for levels of cytokines, which are protein messengers that trigger inflammation. Those with the highest amount of cytokines in their blood were more than twice as likely to develop Alzheimer’s disease as those with the lowest amount of cytokines.
“It’s pretty rare when you can make an animal smarter,” said Dr. James Bibb, assistant professor of psychiatry at the University of Texas Southwestern Medical Center, who led the study published in the journal Nature Neuroscience.
I’ll say. These guys deleted a certain gene, Cdk5, which apparently controls the destruction of the NMDA receptor. The NMDA receptor is important for learning new associations and retaining them as memories. Seems pretty legit.
A shout out to my neighbors with the big press release.
“We found that estrogen has totally opposite effects on behavior in these mice depending only on how much light they got each day,” said Brian Trainor, co-author of the study and postdoctoral fellow in psychology and neuroscience at Ohio State University. “It is quite a surprising finding.”
A pretty cool story on the diminishing marginal utility theory.
The microeconomic law of diminishing marginal utility states that while accumulating a good—pretzels, pencils, nickels, whatever—each successive unit of that good will be less satisfying to acquire than the one before it. Finding a shiny quarter on the street is a real thrill. But, if you are carrying around a bag of coins, acquiring another one does not seem nearly as exciting. In fact, would you even bother to pick it up?
That hesitation is what researchers at the University of Cambridge in England were banking on when they designed a study to see if the haves catch on more slowly than the have-nots when it comes to reward-based learning. Reporting in the current issue of Neuron, the scientists reveal that when a small sum of money is on the line, poorer people learn quickly how to maximize their profits, leaving their wealthier counterparts in the dust.
It’s spring break time here at OSU and many undergrads are driving down to Daytona and Pensacola etc. As they drive through Kentucky and Tennessee, I’m sure they don’t remember much about the drive and the exits once they get to their destination. But, imagine they were driving through Kentucky in search of that glorious elixir, Ale-8-1? Better yet, what if they were assigned to work in Estill county, Kentucky, for a summer selling books door to door? One could imagine that driving through Lexington to get gas would not encode the place as strongly as driving through each of the 6 exits to find the thick green glass bottles of Ale-8-one, the kind that truly insulate that citrusey ginger ale concoction.
Interestingly, the idea that goal representation and motivation play a role in the encoding of spatial memories is still controversial within the neuroscience. I am glad to see scientists rigorously testing the effects of motivation on spatial memory (the hippocampus is the part of the brain that encodes spatial memory, among other things).
The hippocampus contains place cells, which are neurons whose firing frequency increases dramatically when an animal is in a specific location in an environment. This location is known as the place cell’s place field. Reporting in the Journal of Neuroscience, Hok and colleagues show that these cells can also fire when a rat is in an area associated with a particular goal, even if this area is outside a cell’s place field.
It’s probably best to read the whole thing.
Interesting news in nature caught my eye:
A study in Science reported that people with damage to the insula, a brain area involved in the assessment of bodily states, found it much easier to give up smoking than people with lesions in other brain areas. Importantly, the insula-lesioned patients had no urge to start smoking again.
I think I can see where this is going: mandatory insulotomies for smokers, once Hillary is elected.
Obviously I’m delving into Johnny B’s territory here, but I couldn’t resist. Do any of you guys think that there is a slippery slope here just waiting for us to slide down without a snowboard?
Minority Report ended like all Stephen Spielberg movies…happily, and at the last minute, with everyone learning their lessons, no worse for wear.
But it typically doesn’t work that way in the real world. What are the ethical implications of being able to read people’s intentions?
