Posts tagged brain

This is mindboggling!

Neuroscience vs philosophy: Taking aim at free will : Nature News

The experiment helped to change John-Dylan Haynes’s outlook on life. In 2007, Haynes, a neuroscientist at the Bernstein Center for Computational Neuroscience in Berlin, put people into a brain scanner in which a display screen flashed a succession of random letters1. He told them to press a button with either their right or left index fingers whenever they felt the urge, and to remember the letter that was showing on the screen when they made the decision. The experiment used functional magnetic resonance imaging (fMRI) to reveal brain activity in real time as the volunteers chose to use their right or left hands. The results were quite a surprise.

“The first thought we had was ‘we have to check if this is real’,” says Haynes. “We came up with more sanity checks than I’ve ever seen in any other study before.”

The conscious decision to push the button was made about a second before the actual act, but the team discovered that a pattern of brain activity seemed to predict that decision by as many as seven seconds. Long before the subjects were even aware of making a choice, it seems, their brains had already decided.

As humans, we like to think that our decisions are under our conscious control — that we have free will. Philosophers have debated that concept for centuries, and now Haynes and other experimental neuroscientists are raising a new challenge. They argue that consciousness of a decision may be a mere biochemical afterthought, with no influence whatsoever on a person’s actions. According to this logic, they say, free will is an illusion. “We feel we choose, but we don’t,” says Patrick Haggard, a neuroscientist at University College London.

(via jfs1)

Source: nature.com

6Science, brain, choice, consciousness, decision, free will, neuroscience, philosophy, story ideas,

sciencecenter:

Why some seconds seem to last forever

Though our perception of time can be stunningly precise — given a beat to keep, professional drummers are accurate within milliseconds — it can also be curiously plastic. Some moments seem to last longer than others, and scientists don’t know why.

Unlike our other senses, our perception of time has no defined location in our brain, making it difficult to understand and study. But now researchers have found hints that our sense of time stems from specialized units in our brain, channels of neurons tuned to signals of certain time lengths.

“We know keeping track of time is incredibly important, it allows us to coordinate movements, interpret body language,” said optometrist James Heron of the University of Bradford in the UK, lead author of the study in Proceedings of the Royal Society B, Aug. 10. “We know the brain does this routinely and accurately, but we’re not sure how. Our evidence strongly suggests the presence of neural units in the brain that are tuned to different durations.”

(via mothernaturenetwork)

Source: Wired

6biology, brain, neuroscience, psychology, science, time,

Two brain halves, one perception f

sciencenote:

Our brain is divided into two hemispheres, which are linked through only a few connections. However, we do not seem to have a problem to create a coherent image of our environment – our perception is not “split” in two halves. For the seamless unity of our subjective experience, information from both hemispheres needs to be efficiently integrated. The corpus callosum, the largest fibre bundle connecting the left and right side of our brain, plays a major role in this process. Researchers from the Max Planck Institute for Brain Research in Frankfurt investigated whether differences between individuals in the anatomy of the corpus callosum would predict how observers perceive a visual stimulus for which the left and right hemisphere need to cooperate. As their results indicate, the characteristics of specific callosal fibre tracts are related to the subjective experience of individuals.

Source: sciencenote

6science, story ideas, brain,

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