entists not to ignore critique from humanist communities, and encourages the continued interaction
between musicians and scientists. He illustrates the perspectives of neuroscience with studies of
musical imagery, absolute pitch, and music and emotion.
Musical imagery
Investigations of musical imagery show that it is possible to probe internal events by objective mea-
surements. The term ”musical imagery” denominates the experience of ”hearing music in one’s
mind”. In PET studies, Andrea Halpern and Robert Zatorre have found clear similarities between
musical imagery and music perception (1996, 1999). Their results indicate that ”brain activity elicited
during imagery was observed in portions of the auditory cortex and overlapped with the activity elic-
ited by real perception” (p. 7). Zatorre adds that this finding raises interesting questions: How are the
neural traces in sensory cortex that correspond to musical imagery activated? And what is the nature
of creative processes which recombine known elements into novel patterns?
Absolute pitch
The investigations of absolute pitch reported by Zatorre do not provide clear conclusions about brain
mechanisms related to this particular ability (pp. 8-9).
Music and emotion
Concerning music and emotion, Zatorre underscores that emotional responses to music are highly
individual, and depend on social and cultural factors, as well as the context of listening. He presents
two approaches to studying emotional responses, the use of dissonant music, and the investigation
of chills induced by music (pp. 9-12).
First PET study
Zatorre is aware that dissonance, as well as consonance, serves an important role in creating aes-
thetically pleasant music. However, he presupposes that listeners who have been exposed to the
Western tonal idiom to a great extent agree that highly dissonant music tends to be unpleasant (p.
10). In a PET imaging experiment, Anne Blood, Robert Zatorre and colleagues (1999) investigated
emotional responses in a group of subjects who had no more than amateur musical training. The set
of stimuli set consisted of a tonal melody accompanied by chords in variable degrees of dissonance.
The study indicates that exposure to increasing and decreasing consonance is correlated with brain
activity in parahippocampal and orbitofrontal regions. These regions are supposed to mediate be-
tween emotion, on the one hand, and perceptual and cognitive representations on the other (p. 10).
Second PET study
In another PET imaging experiment, Anne Blood and Robert Zatorre (2001) investigated intensely
pleasurable responses to music. The phenomenon in focus was ”chills” or ”shivers down the spine”
elicited by music. ”Chills” are experienced as a a very positive emotion which encompasses measur-
able bodily responses, such as changes in heart rate, respiration, and muscle tension.
Participants were musicians with at least 8 years of music training, selected on the basis of fre-
quent, reproducible experiences of chill responses to music. As music preference is highly individual,
each test subject selected one piece of music that consistently elicited chills. This piece was used
as another subject’s emotionally neutral control, so that chills-inducing and neutral musical samples
were balanced.
Test results of the PET scannings provided evidence that the subjective experience of chills
was correlated with increase in regional cerebral blood flow (rCBF) in a number of brain regions,
including the dorsal^4 midbrain, ventral striatum (which contains the nucleus accumbens), insula,
and the orbitofrontal cortex. Decrease in rCBF during intense chills was observed in portions of the
amygdala (pp. 11-12). During the most intensive chills, heart rate, respiration depth, and muscle ten-
4 ”Dorsal” indicates location toward the back or posterior part of the body. ”Ventral” indicates location toward the front or
anterior part of the body.