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.
Nick Sousanis, who delivered his doctoral dissertation in comic book form, has a new comic in the current Nature magazine, explaining the last 25 years’ worth of climate talks, as a primer in advance of the Paris climate talks next week.
Today only in the Boing Boing Store we are offering an extra 15% off of the below VPN deals just use coupon code: VPN15 at checkout. proXPN VPN: Premium Lifetime Subscription Surf the web with ultimate peace of mind – both at home and on the road – over proXPN’s fully-encrypted, lightning-fast servers. Your lifetime premium subscription […]
These knitted gloves are here to save the day (and your hands) with an ultra-comfy, double-layer that will allow you to stay warm and use your phone. Now you can take photos on the fly, text, Tinder, and more without letting freezing temperatures get in your way. Plus they work with all touchscreens, so no […]