Head size

Definition: Head size in fNIRS research is mostly described by the head circumference (in cm), as measured by wrapping a measuring tape around the head at the level of the nasion in the front, the inion at the back, and the left and right preauricular points (tragi). Head size is needed to choose the best-fitting cap size for the participant to ensure good contact between the optodes and the scalp. Head sizes vary depending on age, gender, and ethnicity. Adults’ average head circumference ranges between approximately 52-58 cm (20-23 inches). For infants, head circumferences range between from 32-48 cm (13-19 inches) in the first year of life (for infants born full term) and increase to about 52-56 cm (20-22 inches) by adolescence.

Alternative definition:

Synonym:

References: ISO 7250: Basic human body measurements for technological design

Related terms: Cap size, Head circumference, Landmark, Headgear