What does the brain do when you're not doing anything in particular? That's when the brain's "default mode network" really kicks into gear. This series of connected regions in the brain is apparently a hot topic for cognitive neuroscientists. This week's issue of Science News surveys research on the default mode network, which apparently is responsible for allowing your mind to "wander." But it also seems to have a much more important role. From Science News:
Default brain settings may lead to daydreaming and mind-wandering, but the network also conducts serious business. Neuroscientists still hotly debate the network’s exact functions, however. Among its jobs may be running life simulations, providing a sense of self and maintaining crucial connections between brain cells. A few researchers doubt the network is anything special at all.
But evidence suggests that a malfunctioning default network is involved in diseases and disorders as diverse as Alzheimer’s disease, autism, depression, post-traumatic stress disorder, Tourette syndrome, amyotrophic lateral sclerosis, schizophrenia and attention-deficit/hyperactivity disorder.
Despite its laid-back name, which neuroscientist Marcus Raichle coined in a 2001 paper, the default mode network is one of the hardest-working systems in the brain. It was discovered accidentally by researchers watching the activity of brains at work on various tasks.
Neuroscientists use PET (short for positron emission tomography) and functional MRI scanners to image and gauge brain activity. To tell which areas of the brain become more active during a mental task, scientists compare brain activity during the task with activity when the person is at rest, either with eyes closed or while staring at a dot or cross. Raichle, of Washington University in St. Louis, and others saw that every time a person engaged in a mental activity such as memorizing a list of words, a collection of brain regions consistently decreased activity compared with their resting levels. Only when people recall autobiographical memories or imagine alternative situations is the network more active than it is at rest, scientists have since found. (In this context, “rest” refers to a state in which the brain is not engaged in a mental task but is still monitoring the body and the world around it.) Raichle hypothesized that the network is more active when the brain is at rest and has to dial back its activity to let people concentrate on specific tasks.
Why does The Caterpillar Lab only have 44 subscribers? Caterpillars set to smooth jazz, like these gorgeous stinging rose caterpillars checking each other out, make this New Hampshire nonprofit a hidden gem.
A paper from a group of Kings College London researchers documents an unexpected and welcome side effect from an experimental anti-Alzheimer’s drug called Tideglusib: test subjects experienced a regeneration of dentin, the bony part of teeth that sits between the pulp and the enamel.
One of the best ways to progress a career in project management is through earning recognized certifications. These certifications carry significant clout and don’t require expensive tuition or student loans. This Ultimate Project Management Certification Bundle is a great example of an affordable way to get ahead. It includes training for 9 certifications including PMP, […]
There’s nothing quite like the rush of playing against a real human opponent. But from a developer standpoint, creating fun multiplayer experiences is incredibly complex. Fortunately, the Unity3D game engine has made all aspects of game creation, including multiplayer functionality, as accessible as ever.This Unity Course Bundle introduces all of the necessary elements of creating […]
The 2016 World Series game 7 will undoubtedly go down in history as one of the greatest baseball games of all time. With endless suspense, a nefariously-timed rain delay, and extra innings, it reminded over 40 million viewers why they love America’s pastime – and why all bets were truly off in 2016. Savor the […]