Functional anatomy of musical processing in listeners with absolute pitch and relative pitch
Abstract
We used both structural and functional brain imaging techniques to investigate the neural basis of absolute pitch (AP), a specialized skill present in some musicians. By using positron emission tomography, we measured cerebral blood flow during the presentation of musical tones to AP possessors and to control musicians without AP. Listening to musical tones resulted in similar patterns of increased cerebral blood flow in auditory cortical areas in both groups, as expected. The AP group also demonstrated activation of the left posterior dorsolateral frontal cortex, an area thought to be related to learning conditional associations. However, a similar pattern of left dorsolateral frontal activity was also observed in non-AP subjects when they made relative pitch judgments of intervals, such as minor or major. Conversely, activity within the right inferior frontal cortex was observed in control but not in AP subjects during the interval-judgment task, suggesting that AP possessors need not access working memory mechanisms in this task. MRI measures of cortical volume indicated a larger left planum temporale in the AP group, which correlated with performance on an pitch-naming task. Our findings suggest that AP may not be associated with a unique pattern of cerebral activity but rather may depend on the recruitment of a specialized network involved in the retrieval and manipulation of verbal-tonal associations.
Content
The existence of special perceptuomotor skills in certain individuals presents many puzzling questions for cognitive neuroscience. One such ability whose cerebral substrate remains essentially unknown is absolute pitch (AP), also known as perfect pitch, a relatively rare ability that refers to a long-term internal representation for the pitch of tones in the musical scale (1, 2). It is typically manifested behaviorally by the ability to identify, by the name of the musical note, the pitch of any sound without reference to another sound or by producing a given musical tone on demand. In contrast, relative pitch (RP), which is well-developed among most trained musicians, refers to the ability to make pitch judgments about the relation between notes, such as within a musical interval.
http://www.pnas.org/content/95/6/3172.full.pdf
PDF – PNAS-1998-Zatorre-3172-7
The functional anatomy of musical processing in listeners with absolute pitch (AP) and relative pitch (RP) has been a subject of interest in neuroscience and cognitive psychology research. Absolute pitch, also known as perfect pitch, refers to the ability to identify or produce musical pitches without reference to an external standard, while relative pitch involves the ability to perceive and recognize the relationships between pitches.
Several neuroimaging studies have investigated the neural correlates of AP and RP to better understand how the brain processes music in individuals with these abilities. While the exact neural mechanisms underlying AP and RP are not fully understood, research has identified several brain regions that may play a role in musical processing:
1. Auditory Cortex: The primary auditory cortex, located in the temporal lobes, is responsible for processing sound information, including musical stimuli. Studies have shown that both AP and RP listeners exhibit activation in the auditory cortex when processing musical stimuli, indicating that this region plays a central role in musical perception.
2. Superior Temporal Gyrus (STG): The STG is involved in higher-level auditory processing, including the perception of pitch, timbre, and melody. Research has found differences in STG activation between AP and RP listeners, suggesting that this region may be involved in the encoding and processing of pitch information.
3. Prefrontal Cortex: The prefrontal cortex, particularly the dorsolateral prefrontal cortex (DLPFC), is implicated in cognitive functions such as working memory, attention, and executive control. Studies have shown that AP listeners exhibit greater activation in the prefrontal cortex compared to RP listeners during tasks involving pitch memory and identification, suggesting that this region may be involved in the maintenance and manipulation of pitch information.
4. Inferior Frontal Gyrus (IFG): The IFG is involved in language processing and cognitive control, but it has also been implicated in musical processing, particularly in tasks involving pitch perception and production. Research has found differences in IFG activation between AP and RP listeners, suggesting that this region may play a role in the cognitive processing of musical pitch.
Overall, the functional anatomy of musical processing in listeners with AP and RP involves a network of brain regions responsible for auditory perception, memory, attention, and cognitive control. Further research is needed to elucidate the specific contributions of these brain regions to the development and expression of AP and RP abilities and to better understand the neural basis of musical processing in general.