Induction of LTP-like changes in human auditory cortex by rapid auditory stimulation: an FMRI study

Abstract

PURPOSE: Previously we have shown that rapid sensory stimulation, in this case, auditory tone pips, can induce long-lasting plastic changes akin to Long Term Potentiation (LTP) within adult human sensory cortex. In a previous study, auditory LTP was reflected as an increase in the amplitude of the N1 component of the auditory event-related potential as measured by EEG. The goal of the present study was to investigate potential effects of LTP-like changes on the hemodynamic response of the human auditory cortex. METHODS: Silent sparse-sampled fMRI recordings were obtained while subjects passively listened to tone-pips both before and after a short block of rapidly presented auditory tone-pips (auditory tetanus) was delivered. RESULTS: The BOLD response within the primary auditory cortex was significantly enhanced after the auditory tetanus. CONCLUSION: This is the first study demonstrating LTP-like changes of the hemodynamic response in the auditory system, and thus supports the growing literature demonstrating LTP can be induced in adult human cortex. These results have implications in the fields of perceptual learning and rehabilitation.