hearing it again and again on-line subcortical plasticity in humans听到一次又一次的在线皮层下人类的可塑性.pdfVIP

Hearing It Again and Again: On-Line Subcortical Plasticity in Humans Erika Skoe1,2*, Nina Kraus1,2,3,4 1 Auditory Neuroscience Laboratory, Northwestern University, Evanston, Illinois, United States of America, 2 Department of Communication Sciences and Disorders, Northwestern University, Evanston, Illinois, United States of America, 3 Department of Neurobiology and Physiology, Northwestern University, Evanston, Illinois, United States of America, 4 Department of Otolaryngology, Northwestern University, Chicago, Illinois, United States of America Abstract Background: Human brainstem activity is sensitive to local sound statistics, as reflected in an enhanced response in repetitive compared to pseudo-random stimulus conditions [1]. Here we probed the short-term time course of this enhancement using a paradigm that assessed how the local sound statistics (i.e., repetition within a five-note melody) interact with more global statistics (i.e., repetition of the melody). Methodology/Principal Findings: To test the hypothesis that subcortical repetition enhancement builds over time, we recorded auditory brainstem responses in young adults to a five-note melody containing a repeated note, and monitored how the response changed over the course of 1.5 hrs. By comparing response amplitudes over time, we found a robust time-dependent enhancement to the locally repeating note that was superimposed on a weaker enhancement of the globally repeating pattern. Conclusions/Significance: We provide the first demonstration of on-line subcortical plasticity in humans. This complements previous findings that experience-dependent subcortical plasticity can occur on a number of time scales, including life-long experiences with music and language, and short-term auditory training.