The 1000 Year Old Brain? Can They Last?
Wang said, "Although we don't yet know why the deletion of the gene altered the mood status of the mice, what we have learned about the importance of this gene in mood function and its involvement in human mental disorders is interesting. The protein encoded by this gene could be a potential drug target for development of diagnostic or therapeutic agents that one day might be used for depression, bipolar or schizophrenia disorders. In addition, the knockout mice might be useful as a model to study mania, as there is no other animal model available yet. __MNTWhen thrown in the deep end of the pool, these PKCI/HINT1 knockout mice never gave up in despair, when all other mice simply rolled over and drowned. They were literally "never say die" mice. Imagine a world of such people.
....the N-methyl-D-aspartate receptor belongs to a family of cellular receptors that mediate excitatory nerve transmission in the brain.
Excitatory signals represent the majority of nerve signals in most regions of the human brain. One theory of causation in Alzheimer's, Parkinson's and multiple sclerosis posits that excessive amounts of the excitatory neurotransmitter, glutamate, can cause an overstimulation of glutamate receptors, including the NMDA receptor. Such excitotoxicity, the theory holds, can cause nerve-cell death and subsequent neurological dysfunction.
...The search is well under way for molecules that can shut down the NMDA receptor with much greater specificity. _MNT
Scientists have known that memories first form in the hippocampus and are later transferred to long-term storage in other parts of the brain. For some amount of time the memory resides both in the hippocampus and elsewhere in the brain. What’s not been known is how, after a few months or years, the memory is gradually cleared from the hippocampus.
Researchers have also debated the role of neurogenesis in learning and memory. The hippocampus is one of only two places in the adult brain where scientists know that new neurons form. On the basis of previous studies, many researchers think new neurons stabilize memory circuits or are somehow otherwise necessary to form new memories.
The new study suggests the opposite: Newborn neurons weaken or disrupt connections that encode old memories in the hippocampus.
Kaoru Inokuchi, a neuroscientist at the University of Toyama in Japan, and his colleagues used radiation and some genetic tricks to block neurogenesis in rats and mice that had been trained to fear getting a mild electric shock when placed in a particular cage. Control animals, with normal neurogenesis, eventually were able to bypass their hippocampi and retrieve the fear memory directly from long-term storage. But animals in which neurogenesis had been blocked still depended on the hippocampus to recall the fear memory, the researchers found.
Running on an exercise wheel, which boosts neurogenesis, also sped the rate at which old memories were cleared from the hippocampus. __Wired
We need good ways of reversing the brain warp induced by early and habitual drug use.
Medical researchers led by Stephen Dewey at The Feinstein Institute for Medical Research and Dr. Jonathan Brodie of New York University School of Medicine recruited parolees who were cocaine dependent, each using an average of two grams of cocaine daily for nine years.It's a start. And in animals, the same drug reduces drug use for most every addictive substance. Of course, it will be harder to make up for the psychological neotenisation caused by poor childraising, abominable educational practises, and a horrifically dumbed down popular culture.
While half the participants in the study received a placebo powder mixed into their juice each day, half got a powder containing vigabatrin. After three months, 14 of the 50 study participants who got vigabatrin each day were able to abstain from cocaine use during the final three weeks of the study, compared with only 4 of the 53 who received the placebo. _MoneyTimes
“We know the brain has been evolving in human populations quite recently,” University of Wisconsin-Madison (UWM) paleoanthropologist John Hawks explains, quoted by LiveScience.Modern cultures of hyper-specialisation may lead to even greater shrinking of the human brain. That could be bad for that 1,000 year lifespan.
“When it comes to recent evolutionary changes, we currently maybe have the least specific details with regard [to] the brain, but we do know from archaeological data that pretty much everywhere we can measure – Europe, China, South Africa, Australia – that brains have shrunk about 150 cubic centimeters, off a mean of about 1,350. That's roughly 10 percent. As to why is it shrinking, perhaps in big societies, as opposed to hunter-gatherer lifestyles, we can rely on other people for more things, can specialize our behavior to a greater extent, and maybe not need our brains as much,” the expert adds. _Softpedia
Smaller brains are typically less intelligent, and will probably be less able to adapt to the lightspeed changes that will hit human populations like truckloads of bricks, every few years to every few dozen years.
Cross-posted at Al Fin
Labels: brain rejuvenation