Brain Activity Codes for Speech at Abstract Level
Coding independent of its visual or auditory features
MONDAY, Dec. 24 (HealthDay News) -- Neural activity in some left hemisphere regions of the brain codes for speech at an abstract level independent of its visual or auditory features, researchers report in the Dec. 20 issue of Neuron.
Uri Hasson, Ph.D., and colleagues from the University of Chicago, used functional MRI to determine which brain regions were activated when 22 subjects were exposed to a target stimulus preceded by stimuli that shared the target's auditory features (auditory overlap), shared the target's visual features (visual overlap), or shared neither but were perceived as the target (perceptual overlap).
The researchers found that there was less activity in the left hemisphere regions pars opercularis and planum polare when the target stimulus was preceded by the perceptually overlapping stimulus.
"This pattern of neural facilitation indicates that these regions code sublexical speech at an abstract level corresponding to that of the speech percept," Hasson and colleagues conclude.