Gyral

Gyral is an adjective used in anatomy and neuroscience to describe features related to the gyri, the elevated ridges on the cerebral cortex of the brain. Gyri (singular gyrus) are separated by sulci, the grooves that create the characteristic folded surface of the cortex. The term derives from Latin gyrus, from Greek gyros, meaning circle or turn.

In neuroanatomy, gyral landmarks are used to refer to specific ridges such as the precentral gyrus (the primary motor cortex) and the postcentral gyrus (the primary somatosensory cortex). Gyral and sulcal terminology helps describe cortical topography in neuroimaging, neurology, and neurosurgery, enabling precise localization of functions and pathology.

Cortical folding, or gyrification, varies among individuals and across species. The extent of gyrification can be quantified by measures such as the gyrification index. Abnormal gyral patterns can be associated with developmental disorders like lissencephaly (a smooth brain with reduced or absent gyri) or polymicrogyria (many small gyri), and are routinely studied in clinical neuroimaging to assess brain development and pathology.

In histology and anatomy, the term gyral may also describe tissue relating to the surface of a gyrus or the organization of neurons on the gyral surface. Overall, gyral features are central to understanding the structure and function of the cerebral cortex.