Recent quotes:

Anesthesia doesn't simply turn off the brain, it changes its rhythms -- ScienceDaily

"All the cortex has to be on the same page to produce consciousness," Miller said. "One theory about how this works is through thalamo-cortical loops that allow the cortex to synchronize. Propofol may be breaking the normal operation of those loops by hyper synchronizing them in prolonged down states. It disrupts the ability of the cortex to communicate." For instance, by making measurements in distinct layers of the cortex, the team found that higher frequency "gamma" rhythms, which are normally associated with new sensory information like sights and sounds, were especially reduced in superficial layers. Lower frequency "alpha" and "beta" waves, which Miller has shown tend to regulate the processing of the information carried by gamma rhythms, were especially reduced in deeper layers.
#synchronize #consciousness #cerebral-cortex #thalamus - sciencedaily.com

Study may show why drugs cure brain disorders in mice but not us - STAT

Scientists have now discovered a key reason for that mouse-human disconnect, they reported on Wednesday: fundamental differences in the kinds of cells in each species’ cerebral cortex and, especially, in the activity of those cells’ key genes. In the most detailed taxonomy of the human brain to date, a team of researchers as large as a symphony orchestra sorted brain cells not by their shape and location, as scientists have done for decades, but by what genes they used. Among the key findings: Mouse and human neurons that have been considered to be the same based on such standard classification schemes can have large (tenfold or greater) differences in the expression of genes for such key brain components as neurotransmitter receptors.
#neurons #mice #models #cerebral-cortex - statnews.com

The Human Brain Is a Time Traveler - The New York Times

In her 1995 paper, Nancy Andreasen included two key observations that would grow in significance over the subsequent decades. When she interviewed the subjects afterward, they described their mental activity during the REST state as a kind of effortless shifting back and forth in time. “They think freely about a variety of things,” Andreasen wrote, “especially events of the past few days or future activities of the current or next several days.” Perhaps most intriguing, Andreasen noted that most of the REST activity took place in what are called the association cortices of the brain, the regions of the brain that are most pronounced in Homo sapiens compared with other primates and that are often the last to become fully operational as the human brain develops through adolescence and early adulthood. “Apparently, when the brain/mind thinks in a free and unencumbered fashion,” she wrote, “it uses its most human and complex parts.”
#brain #memory #meditation #time #cerebral-cortex - nytimes.com

What Is This Thing Called Consciousness?

Yet the cerebellum has everything you expect of neurons. It has gorgeous neurons. In fact, some of the most beautiful neurons in the brain, so-called Purkinje cells, are found in the cerebellum. Why does the cerebellum not contribute to consciousness? It has a very repetitive and monotonous circuitry. It has 69 billion neurons, but they have simple feed-forward loops. So I believe the way the cerebellum is wired up does not give rise to consciousness. Yet another part of the brain, the cerebral cortex, seems to be wired up in a much more complicated way. We know it’s really the cortex that gives rise to conscious experience.
#brain #neurons #consciousness #cerebellum #cerebral-cortex - nautil.us