Sulcal pattern and morphology of the superior temporal sulcus.

The superior temporal sulcus (STs) is the main sulcal landmark of the external temporal cortex and is very important for functional (posterior language areas on the left) mapping and surgery. The methodology we use is based on the extraction of the 3D shape of sulci and their separation into subunits called sulcal roots. Seventeen normal brains (male: 11, female: 6, age: 22-60) were systematically analyzed. Additionally, parameters generated by visual observation were recorded. Non-parametric statistics were performed to evaluate the variation of the STs and influence of side, handedness and sex. We found that the 3D architecture of the STs was consistent with our generic model in four sulcal roots and four "plis de passage" (PP) and significant differences between right and left hemispheres. These morphological differences may be related to the language-relevant cortical areas difference and are pertinent for defining the limits of morphometric variability of the STs in "normal humans".