harmonic complex tones was impaired,^81 again consistent with observations in most right
temporal lobectomy patients with partial or complete excisions involving the primary
auditory cortex.^82 Taken together, these findings are consistent with the hypothesis that
MHS’s impaired consonance perception was related to deficits in pitch processing.
1451008060
4020
0% Accuracy100C 100BA500
0 1/8 1/16 1/4 1/2 1 2 480
60
4020
0% AccuracyControls
M.H.S.In-tune
chordsAll chordsOut-of-tune
chords% Trials judged roughControls
M.H.S.Controls
M.H.S.∆F (semitones)
Root = 880 HzFigure 9.7 Perception of consonance (A and B) and roughness (C) in a patient, MHS, with bilateral lesions of
auditory cortex (Figure 9.2A). (A) Data from Tramo et al.^15 showing response accuracy on a task that required
MHS to determine whether a major triad was ‘in tune’or ‘out of tune’. (B) MHS’s error rate as a function of stimu-
lus condition. (C) Percentage of trials in which two simultaneous pure tones were judged to be fluctuating and
rough (as opposed to steady and smooth) as a function of theF between the tones. The mean (line) and stand-
ard deviation (bars) show the combined performance of 10 normal subjects and eight neurological patients who
did not have bilateral lesions of auditory cortex. Three of the patients had chronic unilateral lesions of superior
temporal cortex (left or right). and one had a lesion of the right inferior colliculus.