Absolute Pitch: An Inside Look
When most people see a wavelength of light, they find no difficulty in associating it with a color. Yet hearing a frequency of sound and associating
it with a musical note is a cognitive talent that fascinates scientists. This rare ability is referred to in the scientific literature as absolute pitch (AP)
and it allows individuals to effortlessly, immediately and accurately label the pitches they hear with a musical note. AP has been a classic example
of the “nature-nurture” dilemma since the extent to which genetic and environmental factors influence it is a matter of constant debate. Current
research though, reveals AP as a paradigm of a complex genetic ...view middle of the document...
Still, numerous inconsistencies and exceptions
in all these theories indicate that AP cannot be fully understood without analyzing its genetic components.
A clearer picture of AP’s genetic basis is emerging through new studies which examine AP’s reoccurrences within families and its relation to other
cognitive conditions. A genetics-based study confirmed that people with AP are likely to have family members who also possess it. This same study
genotyped the DNAs of individuals with AP and linkage analysis was performed. Significant linkage was found in various positions on chromosome
8 with a peak in the specific location 8q24.21 amongst individuals of European ancestry. Further analysis though, implied that despite strong
linkage in this area, the genetic basis of AP displays locus heterogeneity (Theusch et al., 2009). The relationship between AP and another cognitive
phenomenon, synesthesia, further brings to light AP’s genetics. Synesthesia is a trait in which stimulating one sense creates a perception in
another. A recent study performed linkage analysis amongst individuals with AP and synesthesia. The study uncovered modest linkage on
chromosomes 2 and 6 with evidence pointing to several genes in those areas that could potentially be responsible for AP (Gregersen et al., 2013).
The results of both these studies are inconclusive but they highlight AP’s undeniable genetic basis. Yet further research is necessary to connect
these scattered pieces of information.
It is important to examine AP through the lens of neuroplasticity, the idea that neural pathways within the brain can be altered by outside stimuli
during set periods in development to focus them on certain skills. A drug called Valproate (VPA) was studied for its potential to reopen the critical
period in adults, hereby restoring a degree of neuroplasticity to allow them to acquire AP. VPA inhibits the enzyme HDAC whose activity closes the
critical period of auditory learning. In a controlled experiment, participants were given the drug and subsequently trained for targeted AP
development. Results indeed demonstrated that subjects...