Information about how the brain, and memory, works
A recent study reveals that when we focus on searching for something, regions across the brain are pulled into the search. The study sheds light on how attention works.
In the experiments, brain activity was recorded as participants searched for people or vehicles in movie clips. Computational models showed how each of the roughly 50,000 locations near the cortex responded to each of the 935 categories of objects and actions seen in the movie clips.
We talk about memory for ‘events’, but how does the brain decide what an event is? How does it decide what is part of an event and what isn’t? A new study suggests that our brain uses categories it creates based on temporal relationships between people, objects, and actions — i.e., items that tend to—or tend not to—pop up near one another at specific times.
Why do we find it so hard to stay on task for long? A recent study uses a new technique to show how the task control network and the default mode network interact (and fight each other for control).
The task control network (which includes the dorsal anterior cingulate and bilateral anterior insula) regulates attention to surroundings, controlling your concentration on tasks. The default mode network, on the other hand, becomes active when a person seems to be doing 'nothing', and becomes less active when a task is being performed.
We know sleep helps consolidate memories. Now a new study sheds light on how your sleeping brain decides what’s worth keeping. The study found that when the information that makes up a memory has a high value—associated with, for example, making more money—the memory is more likely to be rehearsed and consolidated during sleep.
A new study has found that errors in perceptual decisions occurred only when there was confused sensory input, not because of any ‘noise’ or randomness in the cognitive processing. The finding, if replicated across broader contexts, will change some of our fundamental assumptions about how the brain works.
A new finding points to brain reorganization, rather than brain size, as the driver in primate brain evolution. Data from 17 anthropoid primate species (including humans) across 40 million years has found that around three quarters of differences between the brains of species of monkeys and apes are due to internal reorganization that is independent of size. The prefrontal cortex in particular appears to have played the biggest role in explaining the evolutionary changes in primate brains.
http://phys.org/news/2013-03-organisation-trumps-size-primate-brain.html
More evidence for the importance of glia, previously regarded as mere ‘support cells’ in the brain, comes from a mouse study — which also indicates the role of astrocytes in the evolution of the human brain. The study found that mice that received transplants of human glial progenitor cells learned much more quickly than normal mice.
A rat study has found that infant males have more of the Foxp2 protein (associated with language development) than females and that males also made significantly more distress calls than females. Increasing the protein level in females and reducing it in males reversed the gender differences in alarm calls.
A small pilot study with humans found that 4-year-old girls had more of the protein than boys. In both cases, it is the more communicative gender that has the higher level of Foxp2.
Evidence against an evolutionary explanation for male superiority in spatial ability coves from a review of 35 studies covering 11 species: cuttlefish, deer mice, horses, humans, laboratory mice, meadow voles, pine voles, prairie voles, rats, rhesus macaques and talastuco-tucos (a type of burrowing rodent). In eight species, males demonstrated moderately superior spatial skills to their female counterparts, regardless of the size of their territories or the extent to which males ranged farther than females of the same species.
A small study of “Super Agers” has found a key difference between them and typical older adults: an unusually large anterior cingulate (involved in attention), with four times as many von Economo neurons.