From: MARK TRAMO To: Louis D Braida Cory Bonn •MMIIIMME> Bcc: [email protected] Subject: Revised last Paragraph for our paper: Perception of the "Missing" FO following bilateral and cortex strokes Date: Mon, 19 Feb 2018 18:47:18 +0000 Numerous authors have addressed the question of how a stimulus containing multiple tones evokes a unitary pitch percept (for reviews see Moore 2013 Intro book 6th ed; , de Cheveigne 2005 in Plack & Oxenham book). All the proposed theories fall into two main categories: temporal processing and spectral pattern matching. Pattern recognition models carry out two serial operations: frequency analysis and template matching. For example, Goldstein (1973) postulated that the central auditory system contains an "optimum processor" that carries out a low-level analysis of resolvable stimulus frequencies then at a higher level scans stored templates of harmonic series to find the closest match to the pattern of stimulus frequencies, such that the pitch of the stimulus corresponds to the FO of the template with the best fit. The results of previous lesion effect studies in cats (Whitfield 1980) and humans (Zatorre 1988) employing the method of constant stimuli have been interpreted as evidence that auditory cortex lesions spare frequency analysis and impair pattern matching. However, subsequent studies of neurological patients with auditory cortex lesions using pure-tone stimuli and the adaptive method showed elevations in frequency difference thresholds for pitch direction discrimination (for review see Tramo et al. 2005). However, no direct comparisons between difference thresholds for pure-tones versus missing-FO complex tones were made, so it remained unclear if the elevations in pure-tone difference thresholds might be sufficient to cause the missing-FO pitch discrimination deficits previously reported in cats and neurological patients. The comparisons of difference thresholds measured with pure-tones, harmonic-tone