“Our study shows how two brain regions, namely the auditory cortex and the dorsal frontal lobe, work together for absolute pitch. In the process, we combine two essentially conflicting explanatory approaches for the phenomenon.”
Two theories on absolute pitch
One explanation assumes that people with absolute pitch already categorize the notes at a very early stage of sound processing. In other words, they process tones in the same way as speech sounds and assign them to particular categories, which is referred to as the categorical perception of tones. This theory assumes that the tones are already processed in the primary and secondary auditory cortex in the brain in people with absolute pitch.
Another theory suggests that people with absolute pitch only process the notes later on and associate them with memory information. People with this gift supposedly master the subconscious allocation of the tones to memory information particularly well. These allocations primarily take place in the upper frontal lobe, in the dorsal frontal cortex. “Therefore, both theories make completely different statements regarding the moment and the anatomical location of the special processing and there is evidence to support both theories,” explains Jäncke.
As someone who experiences the phenomenon of synesthesia, married to someone who experiences absolute/perfect pitch, I would offer that these two theories do an excellent job of explaining our worlds; both theories are accurate from our perspective.
Connected brain regions explain the phenomenon
In his study, Stefan Elmer is now able to show that functionally the left-hand auditory cortex and the left-hand dorsal frontal cortex are already strongly linked in a dormant state — in other words, when there are no tasks to be performed. This functional coupling could be estimated based on a mathematical technique, which uses surface electroencephalography to extrapolate the brain activity inside the brain. In people with absolute pitch, the neurophysiological activity in the frontal and auditory cortex are synchronized, which suggests a close functional connection.
This means that the brain regions that control early perception functions (auditory cortex) or late memory functions (dorsal frontal cortex) are already tightly interwoven in a dormant state. “This coupling enables an especially efficient exchange of information between the auditory cortex and the dorsal frontal cortex in people with absolute pitch, which means that the perception and memory information can be exchanged quickly and efficiently,” explains Elmer.