ERIC Number: EJ926123
Record Type: Journal
Publication Date: 2011-Jun
Abstractor: As Provided
Reference Count: 0
Cortical Spatio-Temporal Dynamics Underlying Phonological Target Detection in Humans
Chang, Edward F.; Edwards, Erik; Nagarajan, Srikantan S.; Fogelson, Noa; Dalal, Sarang S.; Canolty, Ryan T.; Kirsch, Heidi E.; Barbaro, Nicholas M.; Knight, Robert T.
Journal of Cognitive Neuroscience, v23 n6 p1437-1446 Jun 2011
Selective processing of task-relevant stimuli is critical for goal-directed behavior. We used electrocorticography to assess the spatio-temporal dynamics of cortical activation during a simple phonological target detection task, in which subjects press a button when a prespecified target syllable sound is heard. Simultaneous surface potential recordings during this task revealed a highly ordered temporal progression of high gamma (HG, 70-200 Hz) activity across the lateral hemisphere in less than 1 sec. The sequence demonstrated concurrent regional sensory processing of speech syllables in the posterior superior temporal gyrus (STG) and speech motor cortex, and then transitioned to sequential task-dependent processing from prefrontal cortex (PFC), to the final motor response in the hand sensorimotor cortex. STG activation was modestly enhanced for target over nontarget sounds, supporting a selective gain mechanism in early sensory processing, whereas PFC was entirely selective to targets, supporting its role in guiding response behavior. These results reveal that target detection is not a single cognitive event, but rather a process of progressive target selectivity that involves large-scale rapid parallel and serial processing in sensory, cognitive, and motor structures to support goal-directed human behavior.
Descriptors: Sensory Integration, Task Analysis, Evaluation Methods, Brain, Neurological Organization, Science Education, Cognitive Processes, Behavior
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Publication Type: Journal Articles; Reports - Research
Education Level: N/A
Authoring Institution: N/A