the clearest signs of not being [adaptive]’,^3 yet in all cultures most people enjoy music. On
the other hand, it takes severe mental retardation to prevent language acquisition, whereas
musical aptitude ranges from tone deafness to Mozartian genius independently of other
measures of intelligence.^4 Estimates of absolute pitch in the general population range from
1 in 1500 to 1 in 10,000.^5
Clues as to how the brain processes music come from clinical case reports of patients with
deranged musical function, from psychological testing of either normal or brain-damaged
subjects, and, more recently, from studies using functional imaging (positron emission
tomography [PET] and functional magnetic resonance imaging [fMRI]). Neurological
symptoms can be positive or negative. Positive phenomena include musicogenic epilepsy,
musical partial seizures, musical release hallucinations, and synesthesia. Negative phenomena
include the amusias.Positive phenomena
Musicogenic seizures are triggered by hearing music. Attacks typically begin with subjective
distress, agitation, tachycardia, and tachypnea and may or may not generalize to grand mal.
Victims are often musically talented but do not have to be. The stimulus can be quite
specific—for example, classical vs popular music, or a particular piece. Reported triggers
include the second movement of Beethoven’s Symphony No. 5 and a sequence of church
bells with a frequency range of less than one octave.6,7In one case seizures occurred only if
the patient actively listened to the music. In another, seizures could be precipitated by back-
ground music of which the patient was barely aware. Seizures have been triggered by the
voices of particular singers.^8 A two-year-old boy’s seizures were precipitated by his own
singing.^9 In another case seizures were triggered by playing ‘Now Thank We All Our God’ on
the organ but not by hearing it, singing it, silently reading it, or silently playing the notes on
the keyboard.^10 Lesions causing musicogenic epilepsy are usually in the temporal lobe, right
more often than left.^11
Musical partial seizures consist of hallucinated music, which can be of any type but
tends to be stereotypic for a particular epileptic subject. Such patients are less likely than
those with musicogenic epilepsy to be musically talented. In a reported series of 666
temporal lobe epileptics, 16 per cent had auditory hallucinations, the great majority of
which were unformed (e.g. banging, ticking).^12 Formed hallucinations could be verbal,
musical, or both. In a more detailed description of hallucinatory seizures precipitated by
cortical electrical stimulation, subjective phenomena included a male chorus and orches-
tra singing ‘White Christmas’, a radio jingle, organ music, and an orchestra playing in
a music hall, which was simultaneously visually hallucinated.^13 Seizures most predictably
followed stimulation of the superior temporal gyrus, right more often than left.
Interestingly, spoken words also followed either left or right hemispheric stimulation, and
there was no topographical separation between areas precipitating voices and those
precipitating music.
Visual or auditory hallucinations associated with impaired vision or deafness (‘Charles
Bonnet syndrome’, release hallucinations) can consist of music; they most often affect
elderly people with presbycusis. Neither dementia nor psychiatric disease need be present,182 Zat-Ch12.qxd 6/6/03 3:43 AM Page 182