Wednesday, December 29, 2010

Before You See It . . .

According to new research done at Duke University, neurons in the brain predict and edit what you see before you see it. And the brain's visual circuits perform "error correction" on the fly. The fMRI study results have led to a new picture of human vision (labeled predictive coding) and challenge the currently held model of sight. The study could change the way in which neuroscientists study the brain. It seems that vision is more complex than scientists previously believed. Apparently, the current picture of human vision (called feature detection) is incomplete. The new data show the brain predicts what it will see and edits those predictions in a top-down mechanism.

Friday, December 24, 2010

And Prosopagnosia

Prosopagnosia (sometimes known as face blindness) is a condition that involves an impairment in the ability to recognize faces (e.g., severe difficulty recognizing faces). The ability to recognize other objects may be relatively intact. The term originally referred to a condition following acute damage to the brain. Recently, however, a congenital form of the disorder has been proposed, which may be inherited by about 2.5% of the population. The specific brain area usually associated with prosopagnosia is the gusiform gyrus. (Grüter T, Grüter M, Carbon CC (2008). "Neural and genetic foundations of face recognition and prosopagnosia". J Neuropsychol 2 (1): 79–97. doi:10.1348/174866407X231001. PMID 19334306.)