Establishing a Visual Guideline for the Locus of Auditory Cortex in Humans

Abstract

Given the variability of human brain anatomy, there is a need to develop a guideline for visually identifying important auditory structures. Traditionally, visual guidelines have been taught in order to help clinicians quickly and reliably identify central auditory structures in the brain. However, the reliability of some of these guidelines have been accepted at face value but not necessarily studied extensively. This study examines the location of Heschl’s gyrus along the superior temporal plane and the consistency of the “two-thirds rule” – which states that Heschl’s gyrus appears in the most posterior third of the superior temporal plane. Heschl’s gyrus and intra-hemispheric measures along the superior temporal plane are examined, with new data reported. The relationship between the two-thirds rule and other variables such as: gender, hemisphere, the angle of Heschl’s gyrus, the number of Heschl’s gyri, and the type of ascending ramus are observed.