title: Conscious and unconscious processing of nonverbal predictability in Wernicke's area.
abstract: The association of nonverbal predictability and brain activation was examined using functional magnetic resonance imaging in humans. Participants regarded four squares displayed horizontally across a screen and counted the incidence of a particular color. A repeating spatial sequence with varying levels of predictability was embedded within a random color presentation. Both Wernicke's area and its right homolog displayed a negative correlation with temporal predictability, and this effect was independent of individuals' conscious awareness of the sequence. When individuals were made aware of the underlying sequential predictability, a widespread network of cortical regions displayed activity that correlated with the predictability. Conscious processing of predictability resulted in a positive correlation to activity in right prefrontal cortex but a negative correlation in posterior parietal cortex. These results suggest that conscious processing of predictability invokes a large-scale cortical network, but independently of awareness, Wernicke's area processes predictive events in time and may not be exclusively associated with language.
authors.affiliation: Department of Neurology, Emory University School of Medicine, Atlanta, Georgia 30322, USA.
authors.forename: A
authors.initials: A
authors.lastname: Bischoff-Grethe
authors.forename: S M
authors.initials: SM
authors.lastname: Proper
authors.forename: H
authors.initials: H
authors.lastname: Mao
authors.forename: K A
authors.initials: KA
authors.lastname: Daniels
authors.forename: G S
authors.initials: GS
authors.lastname: Berns
mesh_terms: D000328:Adult; D003116:Color; D003243:Consciousness / Q000502:physiology*; D019277:Entropy; D006801:Humans; D008279:Magnetic Resonance Imaging; D008606:Mental Processes / Q000502:physiology*; D008875:Middle Aged; D010775:Photic Stimulation; D011336:Probability; D013060:Speech; D013702:Temporal Lobe / Q000502:physiology*; D014473:Unconscious, Psychology