Conscious and unconscious processing of nonverbal predictability in Wernicke's area

J Neurosci. 2000 Mar 1;20(5):1975-81. doi: 10.1523/JNEUROSCI.20-05-01975.2000.


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.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Adult
  • Color
  • Consciousness / physiology*
  • Entropy
  • Humans
  • Magnetic Resonance Imaging
  • Mental Processes / physiology*
  • Middle Aged
  • Photic Stimulation
  • Probability
  • Speech
  • Temporal Lobe / physiology*
  • Unconscious, Psychology*