2011 年 30 巻 1 号 p. 115-120
I discussed cognitive processing of music in the brain through a neuropsychological approach. The case 1 showed an impairment of chord perception and, in singing familiar songs, replacement of phrases (paramelodia), due to infarction of anterior portions of bilateral temporal lobes. We performed a positron-emission-tomogoraphy (PET) activation study in order to clarify the brain regions which participated in chord perception. As a result, anterior portions of bilateral temporal lobes were activated. We can reasonably conclude that these brain regions have a relationship with chord perception. The case 2 had infarction of bilateral temporal lobes, and revealed word deafness, environmental sound agnosia, and receptive and expressive amusia. Though the patient showed impaired scores in tasks of chord and pitch discrimination, recognition of tonality was normal. Though the patient showed impaired scores in tasks of chord and pitch discrimination, recognition of tonality was normal. Tonality turned out to be one of the independent factors of receptive processing of music. We revised the Peretz's model of music processing in the brain.