Brain complexity: review article (Introduction)

by David Turell , Tuesday, July 21, 2015, 11:49 (3414 days ago) @ Balance_Maintained

A very clear exposition of how the brain works to build our perceptions:-http://medicalxpress.com/news/2015-07-william-james-revisited-ongoing-brain.html-"The paper raises the fundamental question of why the brain's processing architecture constantly undergoes such spatially extended modulations, as well as the possibility that in more complex decision-making or working memory engagement, behavior would benefit from less modularity and thereby more widespread communication between task-relevant modules. "While in the recent few years it has become increasingly apparent that ongoing functional connectivity across brain regions is constantly changing, the reason for these dynamics is largely unknown," Sadaghiani notes. "One interpretation is that these dynamics could be merely an epiphenomenal byproduct of how spontaneous electrical activity flows through the brain's anatomical wiring - but another much more exciting possibility is that by dynamically shifting between various connectivity states, the brain iterates through connectivity layouts that facilitate different types of cognitive functions. For example," she illustrates, "one moment the brain may be in a state that is optimal for sensory perception, such as a highly modular structure where sensory networks are well segregated as observed in the current perceptual experiment. In the next moment, the brain may be in a more integrated state where widespread communication across networks facilitates higher-level cognitive functions such as semantic memory retrieval or complex reasoning." This interpretation suggests that by continuously changing configurations within an array of connectivity states, the brain could exploit its full cognitive potential.-"The paper also states that attempts to link behavior to brain function must conceptually integrate the role of ongoing brain activity and its connectivity dynamics. "Almost all neuroscientific approaches to studying the neural basis of cognitive processes - from single cell recordings to large-scale network imaging - inherently assume that the brain is primarily a reactive machine and mainly fires in response to a stimulus or cognitive challenge." Sadaghiani says. "While this assumption greatly simplifies experimentation and analyses, during the last decade or so overwhelming evidence across all these methodologies shows that most of brain activity is in fact intrinsic and not dependent on external events. In fact, a growing body of studies - including ours - suggests that this intrinsic brain activity influences our perception of the world and cognition."
 (my bold)