Contralateral induction by frequency spectrum in hallucinating schizophrenics

Psychiatry Res. 1999 Jul 30;87(1):65-75. doi: 10.1016/s0165-1781(99)00040-2.


Seventeen schizophrenic patients who had all experienced auditory hallucinations were compared with 14 subjects of a reference group on a test of contralateral induction. Contralateral induction means that a sound is illusively heard as coming from a location where it belongs according to its spectral content. The phenomenon is connected with a simultaneous relative elimination of masking. The schizophrenic subjects deviated from the reference group in several aspects. Some of them did not hear the sound being induced to the contralateral side, which it was for all reference subjects. Another subgroup of the schizophrenics noticed the induction unusually early with a prolonged experience of it, and finally some of them experienced the induction now and then. The aberrations were interpreted as rigidity of adaptation on the one hand and as effects of an enhanced sensitivity on the other. Discontinuity, meaning that the fluency in mental processing is broken, was interpreted to cause the ratings of the third group of schizophrenics in this sample, who heard the contralateral induction now and then. These phenomena are clearly reminiscent of descriptions in research reports, and witnessed by clinical experience of the schizophrenic disturbance. The results represent another example of discontinuous neurophysiological functions between neural systems and between individuals suffering from schizophrenia.

MeSH terms

  • Adult
  • Anxiety / physiopathology
  • Case-Control Studies
  • Cues
  • Female
  • Hallucinations / physiopathology*
  • Humans
  • Illusions / physiology*
  • Male
  • Middle Aged
  • Perceptual Masking / physiology
  • Pitch Perception / physiology
  • Psychoacoustics*
  • Schizophrenia / physiopathology*
  • Sound Localization / physiology*
  • Time Factors