N1b and Na subcomponents of the N100 long latency auditory evoked-potential: neurophysiological correlates of voicing in French-speaking subjects

Clin Neurophysiol. 2009 May;120(5):897-903. doi: 10.1016/j.clinph.2009.02.174. Epub 2009 Mar 28.

Abstract

Objective: To look for the presence of neurophysiological correlates of language-general voicing boundaries in French by analyzing the morphology of two N100 subcomponents (N1b and T-complex).

Methods: /d/ and/t/ syllables with a voice onset time (VOT) value varying evenly from -75 and +75 ms were presented to French-speaking adults as stimuli for scalp-recorded auditory evoked-potentials. Morphologies and peak latencies of N1b and T-complex subcomponents were assessed.

Results: The Na subcomponent of the T-complex was double-peaked for VOT values below -30 ms and above +30 ms. N1b subcomponent revealed a double-peaked response above +30 ms VOT and a single-peaked response for all other VOT values. Whenever the response was double-peaked, there was a correlation between the VOT value and the N1b or Na supplementary peak latency.

Conclusions: The combined morphologies of N1b and Na yield clear neurophysiological correlates of the language-general boundaries. For negative VOT values, the differential behavior of N1b and Na subcomponents suggests that only Na possesses physiological properties indexing the two language-general boundaries.

Significance: Rather than being lost, the universal sensitivity of human newborns to language-general boundaries remains present even if in some languages such as French, they do not separate phonological categories.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acoustic Stimulation
  • Adult
  • Brain Mapping / methods
  • Cerebral Cortex / anatomy & histology
  • Cerebral Cortex / physiology*
  • Electroencephalography / methods
  • Evoked Potentials, Auditory / physiology*
  • Female
  • France
  • Humans
  • Language Tests
  • Language*
  • Male
  • Reaction Time / physiology*
  • Speech Acoustics*
  • Speech Perception / physiology*
  • Time Factors
  • Young Adult