Neuroscience

An important prerequisite for intelligence is a good short-term memory which can store and process the information needed for ongoing processes. This 'working memory' is a kind of mental notepad – without it, we could not follow a conversation, do mental arithmetic or play any simple game. A new study has discovered neurons allowing crows to remember short-term. In the animal kingdom, the group of birds including crows and ravens, the corvids, are known for their intelligence because they have just such a working memory, but their endbrain – which is highly-developed but has a…

Young children instinctively use a ‘language-like’ structure to communicate through gestures, a result which suggests that children are not just learning language from older generations, but instead their preference for communication has shaped how languages look today. In the paper, the research team examined how four-year-olds, 12-year-olds and adults used gestures to communicate in the absence of speech. The study investigated whether their gesturing breaks down complex information into simpler concepts. This is similar to the way that language expresses complex information by breaking it…

The recent study from UC-San Diego on memories in rats, published in the June 1 Nature, confirms the long-standing suspicion that memories are formed based on the strength of the synapses, and deteriorate as the connections of those synapses weaken. More importantly, the results of the study show that memories are more pliable that we might have thought - using an optic technique, memories can be deactivated, then reactivated. According to USNews, lead author Sadegh Nabavi said, "We can cause an animal to have fear and then not have fear and then to have fear again by stimulating the nerves…

A new study in the journal Molecular Psychiatry has linked children who later developed autism with exposure to elevated levels of steroid hormones (for example testosterone, progesterone and cortisol) in the womb. The team, led by Professor Simon Baron-Cohen and Dr. Michael Lombardo in Cambridge and Professor Bent Nørgaard-Pedersen in Denmark,  caution that while this may help explain why autism is more common in males than females, it should not be used to try and screen for the condition.   The results were generated based on almost 20,000 amniotic fluid samples stored in a…

New research in the journal Sleep and being presented Wednesday, June 4th in Minneapolis at SLEEP 2014 suggests that marijuana use is associated with impaired sleep quality. The results show that any history of cannabis use was associated with an increased likelihood of reporting difficulty falling asleep, struggling to maintain sleep, experiencing non-restorative sleep, and feeling daytime sleepiness. The strongest association was found in adults who started marijuana use before age 15; they were about twice as likely to have severe problems falling asleep (odds ratio = 2.28), experiencing…

A group of researchers have erased memories in rats, profoundly altering the animals' reaction to past events. Then they put them back. The study is the first to show the ability to selectively remove a memory and predictably reactivate it by stimulating nerves in the brain at frequencies that are known to weaken and strengthen the connections between nerve cells - synapses. The scientists optically stimulated a group of nerves in a rat's brain that had been genetically modified to make them sensitive to light, and simultaneously delivered an electrical shock to the animal's foot. The rats…

Twenty years after the hormone leptin was found to regulate metabolism, appetite, and weight through brain cells called neurons, a new study in Nature Neuroscience says that the hormone also acts on other types of cells to control appetite. Leptin, a naturally occurring hormone, is known for its hunger-blocking effect on the hypothalamus, a region in the brain. Food intake is influenced by signals that travel from the body to the brain. Leptin is one of the molecules that signal the brain to modulate food intake. It is produced in fat cells and informs the brain of the metabolic state. If…

How much free will do you really have? Hypnosis is silly and there is no "Manchurian Candidate" scenario happening any time soon, but we're all inductance when you get right down to it. And that could be a future path in neuroscience. A study Current Biology writes of a causal link between activity in the ventral tegmental area and choice behavior in primates; when electrical pulses are applied to the ventral tegmental area of their brain, macaques presented with two images change their preference from one image to the other.  The ventral tegmental area is located in the midbrain and…

People who engage in binge eating, substance abuse and obsessive compulsive disorder all share a common pattern of decision making and similarities in brain structure, according to a  new paper in Molecular Psychiatry. In our daily lives, we make decisions based either on habit or aimed at achieving a specific goal. For example, when driving home from work, we tend to follow habitual choices – our 'autopilot' mode – as we know the route well; however, if we move to a nearby street, we will initially follow a 'goal-directed' choice to find our way home – unless we slip into autopilot…

Men with gender dysphoria, commonly called gender identity disorder, are born as males but behave as and identify with women and want to change sex. Around puberty, the testes of men start to produce androstadienone, a musky-smelling steroid produced by men as a breakdown product of testosterone. Men release it in their sweat, especially from the armpits. Its only known function is to work like a pheromone; when women smell androstadienone, their mood tends to improve, their blood pressure, heart rate, and breathing go up, and they may become aroused.  The brains of children with…