Experimental Brain Research

, Volume 71, Issue 1, pp 87–92

Modification of neuromagnetic responses of the human auditory cortex by masking sounds

  • R. Hari
  • J. P. Mäkelä

DOI: 10.1007/BF00247524

Cite this article as:
Hari, R. & Mäkelä, J.P. Exp Brain Res (1988) 71: 87. doi:10.1007/BF00247524


We have studied the effects of masking sounds on auditory evoked magnetic fields (AEFs) of healthy humans. The AEFs were elicited by 25-ms tones presented randomly to the left or to the right ear, and the responses were recorded over the right auditory cortex. Without masking, the 100-ms deflection (N100m) was of somewhat higher amplitude and of shorter latency for contrathan ipsilateral stimuli. Continuous speech, music, or intermittent noise, delivered to the left ear, dampened N100m to stimulation of both ears without correlated changes in sensation. Intermittent noise had a weaker effect on N100m than speech or music. Continuous noise fed to the left ear dampened both the sensation of and the responses to the left-ear stimuli, with no significant effect on the responses to the right-ear stimuli. The results suggest that the masking effects of continuous noise, seen at the auditory cortex, derive mainly from the periphery whereas the effects of sounds with intensity and frequency modulations take place at more central auditory pathways.

Key words

Auditory cortexMagnetoencephalographyContraand ipsilateral stimulationEvoked responsesMaskingMan

Copyright information

© Springer-Verlag 1988

Authors and Affiliations

  • R. Hari
    • 1
  • J. P. Mäkelä
    • 1
  1. 1.Low Temperature LaboratoryHelsinki University of TechnologyEspooFinland