Psychophysical measurement of the audiogram of the common marmoset using saccadic eye movements

Musical Knowledge Influences Auditory Encoding In The Brainstem Marmel, Frederic; Parbery-Clark, Alexandra; Skoe, Erika; Kraus, Nina Auditory Neuroscience Laboratory, Northwestern University (http://www.brainvolts.northwestern.edu/) In Western music, the relations between pitch events are determined by the tonal system. In the last 30 years, a large number of studies have shown that auditory processing is influenced by listener's implicit knowledge of these tonal relations. Notably, Bhaucha & Stoeckig (1986, 1987) showed facilitated processing of a chord when it was preceded by a tonally related chord in comparison to when it was preceded by a tonally less-related chord. Tonal relatedness was also found to influence auditory processing at early cortical steps (Koelsch et al., 2007; Krohn et al., 2007; Marmel et al., 2008). The present study investigated the influence of listeners’ implicit tonal knowledge on subcortical auditory processing at the brainstem level. The specific hypothesis was that a chord would show more robust brainstem encoding when preceded by a tonally related chord than when preceded by a less related chord. Participants listened to pairs of chords while watching a silent movie and having their brainstem responses recorded. The two chords of the pairs were either tonally related (G chord → C chord), less tonally related (F# chord → C chord), or were a repetition of the same C chord. Differences between the second chord (C chord) in the three conditions were analyzed in terms of average spectral response amplitudes, strength of envelope periodicity, and sharpness of phase locking. The implications of this study are to provide a first evidence that abstract relations between stimuli can influence auditory processing as early as the subcortical processing steps, thus underlining the plasticity of the auditory system to our cultural environment. Support: Fyssen Foundation (http://www.fondation-fyssen.org/indexus.html) Brainstem correlates of speech in noise perception Judy Song, Erika Skoe, Karen Banai, Nina Kraus Auditory Neuroscience Laboratory, Departments of Communication Sciences, Neurobiology and Physiology, Otolaryngology at Northwestern University, Evanston, IL 60208. Department of Communication Sciences and Disorders at University of Haifa, Haifa 31905 The perpetual presence of irrelevant auditory information (other talkers, environmental noises) presents a major challenge to listening in speech. The fundamental frequency (F0) of the target speaker is thought to provide an