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POPSHuman-frog hybrids reveal autism's secrets To see if abnormalities in neurotransmitter signalling also underlie autism, Miledi's team collected brain samples from six deceased autistic patients, aged eight to 39. They fused brain-cell membranes, which house neurotransmitter receptors, together with Xenopus egg membranes. As a control, they did the same thing with brain cells from patients with no history of mental disorder. Miledi's team then doused the frog eggs in neurotransmitter chemicals, and measured the voltage generated within each egg. The neurotransmitter chemicals tell brain cells to pump charged molecules in and out the membrane, creating a voltage across the membrane. Since Xenopus eggs do not respond to the neurotransmitters, the human proteins are completely responsible for any electric current generated. Four of six autistic brains responded to neurotransmitters chemicals less vigorously than the controls.
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POPSTo Trust or Not to Trust? It has been hypothesized that oxytocin, a hormone recognized for its role in social attachment and facilitation of social interactions, is also important in the formation of trust. For instance, application of oxytocin to “investors” in experimental games increases their tendency to engage in social risks and trust someone else with their money (see this and this). The study by Baumgartner and his colleagues highlights the neural mechanisms through which oxytocin acts to facilitate trust behavior by investigating what happens in the brain when trust breaks down.
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POPSUnderstanding Hearing, Molecule By Molecule other sensory system in biology and the electrical engineering world is capable of this feat. “It’s one of the most beautifully deigned systems in the body,” says Manfred Auer of Berkeley Lab's Life Sciences Division. “But how it really works remains a mystery. Our goal is to determine what the system looks like, so we can determine how it functions.”
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POPSWill Our Future Brains Be Smaller? Why does the brain need these two decision-making areas? What benefit does the new cortex bring? After all, extra brain means extra weight and energy required to carry it around. Furthermore, is the older sub-cortical system now largely redundant? If so, could we expect it to atrophy in future humans so our brains become smaller? The results of their modelling showed that when the threat level is high, such as the risk of being attacked by a dangerous animal, it is very useful to have the fast-acting, if inaccurate, system. But when dealing with situations which don't occur very often, or complex scenarios with many conflicting cues such as social situations, the cortical system is of more use than the sub-cortical system.
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POPSEnding Moderate Drinking Tied To Depression The mice were tested for depression-like behavior using a widely recognized method called the Porsolt Swim Test. The mice are placed inside a beaker filled with water and allowed to swim for six minutes. Mice are good swimmers and have no problem completing this task. The amount of time they spend immobile (floating and not swimming) is measured as an index of despair or depression-like behavior. The more time a mouse spends immobile, the more "depressed" it is thought to be. "This research provides the first evidence that long-term abstinence from moderate alcohol drinking -- rather than drinking per se -- leads to a negative mood state, depression," Hodge said.
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POPSMechanism and function of humor identified by new evolutionary theory "By removing stipulations of content we have been forced to study the structures underlying any instance of humour, and it has become clear that it is not the content of the stimulus but the patterns underlying it that provide the potential for sources of humour. For patterns to exist it is necessary to have some form of content, but once that content exists, it is the level of the pattern at which humour operates and for which it delivers its rewards." Previous theories have only ever applied to a small proportion of all instances of humour, many of them stipulating necessary content or social conditions either in the humour itself or around the individual experiencing it. But this doesn't explain why an individual can laugh at something when no one else around them does, nor why two people can laugh at the same stimulus for different reasons.
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POPSGet Out of Your Own Way In ways we are only beginning to understand, the synapses and neurons in the human nervous system work in concert to perceive the world around them, to learn from their perceptions, to remember important experiences, to plan ahead, and to decide and act on incomplete information. In a rudimentary way, they predetermine our choices.
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POPSArtificial brain predicts death-row executions Since the direct approach had failed, the researchers turned to an artificial neural network (ANN) - an intelligent computer system, modelled after the human brain - that is able to deduce how various factors within a jumble of data relate to each other. The system can then take what it has learned and make predictions about a new set of data.To find out which factors might be linked to executions, the researchers first "trained" their ANN by entering the profiles of 1000 death row inmates between 1973 and 2000. Half of this sample of prisoners had been executed and the other half had survived. Each profile contained 18 factors, including the inmate's sex, age, race, marital status, educational level and information on their capital offences.
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POPSNew Research On Octopuses Sheds Light On Memory It is not completely understood how these two systems are interconnected, if at all. However, the organization in the octopus demonstrates a sophistication that was not described yet in other animals. In the octopus, the short-term and long-term systems are working in parallel, but not independently. This is so because the long-term memory area -- in addition to its capacity to store long-term memories -- also regulates the rate at which the short-term memory system acquires short-term memories. This regulatory mechanism is probably useful in cases where faster learning is significant for the octopus' survival in emergency or risky situations.
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POPSOf Two Minds, One Consciousness But perhaps even more profound, he explains how, even though split-brain patients have isolated hemispheres, they experience a unified consciousness—that is, feel as though they are of one mind.
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POPSObituary: Lorenzo Odone Reasoning that they could combat the disease by reducing the levels of very-long-chain fatty acids, they developed an oil derived from rapeseed and olive oil. When they gave the oil to Lorenzo, it reduced the levels of very-long-chain fatty acids in his blood, by blocking the enzymes that make them. The devotion and determination of Lorenzo's parents helped prolong his life and inspired the film, which came out in 1992. After its release, scientists were angered by suggestions that the oil was a cure for the disease.
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POPSParalysed man takes a walk in virtual world It is the first time a paralysis patient has succeeded in meeting a person and having a conversation in an Internet virtual world, they added. Researchers are now studying a system that would let patients create text messages by mentally selecting certain letters, said Junichi Ushiba, associate professor at the biosciences and informatics department of Keio Universty's Faculty of Science and Technology. "In the near future, they would be able to stroll through Second Life shopping malls with their brain waves... and click to make a purchase," Ushiba said.
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POPSIn the Works: MEMS Brain-Computer Interface As the electrodes are driven into the tissue, the software starts taking sample recordings to detect spikes of electrical activity at the electrode tip. When the software detects spikes, it moves forward in small increments and tracks how the signals change. After determining whether the signal has improved or gotten worse, it the algorithm moves the electrode to a new position and does more recording and comparing, driving the electrode in further if necessary until it finds the best signal. If the signal wanes, the algorithm will automatically adjust the electrode position to improve the signal.
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POPSReligion is a product of evolution, software suggests Another contends that religion benefited our ancestors. Rather than being a by-product of other brain functions, it is an adaptation in its own right. In this explanation, natural selection slowly purged human populations of the non-religious. To determine if it was possible for religion to emerge as an adaptation, Dow wrote a simple computer program that focuses on the evolutionary benefits people receive from their interactions with one another.
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POPSExploring The Mechanics Of Judgment & Beliefs "We already knew that some parts of the brain are involved in specific aspects of perception and motor control, but many doubted that an abstract high-level cognitive process like understanding another person's thoughts would be conducted in its own private patch of cortex," Kanwisher says.
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POPSCan You Catch Up on Lost Sleep? The good news is that, like all debt, with some work, sleep debt can be repaid—though it won't happen in one extended snooze marathon. Tacking on an extra hour or two of sleep a night is the way to catch up. For the chronically sleep deprived, take it easy for a few months to get back into a natural sleep pattern, says Lawrence J. Epstein, medical director of the Harvard-affiliated Sleep HealthCenters. Go to bed when you are tired, and allow your body to wake you in the morning (no alarm clock allowed). You may find yourself catatonic in the beginning of the recovery cycle: Expect to bank upward of ten hours shut-eye per night. As the days pass, however, the amount of time sleeping will gradually decrease.
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POPS'Babelfish' to translate alien tongues could be built But Deacon argues that all languages arise from the common goal of describing the physical world. That limits the way a language could be constructed, he concludes. An alien race could use a strange medium like scents as their language, Deacon says, but the scents would still describe objects in their world. An odour that communicates "rock" or "tree" would be analogous to our words for the same objects. So there must be an underlying universal code that can be deciphered, as in mathematics.
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POPSBrain Waves Pattern Themselves After Rhythms Of Nature Although the bulk of his work involves deriving equations, Cowan's findings mesh well with laboratory data generated on the cerebral cortex and electroencephalograms. His latest findings show that the same mathematical tools physicists use to describe the behavior of subatomic particles and the dynamics of liquids and solids can now be applied to understanding how the brain generates its various rhythms.
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POPSA Speech Center of the Monkey Brain Has Been Found! The researchers played recorded coos, grunts, and other vocalizations made by macaques, but also other animals and natural sounds like thunder and running water. A small area of the macaques' temporal lobes turned on only in response to macaque voices, being insensitive to other sounds. The nucleus could differentiate the voices of individual macaques: its activity decreased when the researchers played several times a monkey's voice, but it was boosted by a new played voice.
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POPSBrain rewards aggression much like it does sex, food, drugs For the experiments, a pair of mice — one male, one female — was kept in one cage and five "intruder" mice were kept in a separate cage. The female mouse was temporarily removed, and an intruder mouse was introduced in its place, triggering an aggressive response by the 'home' male mouse. Aggressive behavior included tail rattle, an aggressive sideways stance, boxing and biting. The home mouse was then trained to poke a target with its nose to get the intruder to return, at which point it again behaved aggressively toward it. The home mouse consistently poked the trigger, which was presented once a day, indicating it experienced the aggressive encounter with the intruder as a reward. The same "home" mice were then treated with a drug that suppressed their dopamine receptors. After this treatment, they decreased the frequency with which they instigated the intruder's entry.
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