HANDEDNESS AND THE BILATERAL ASYMMETRY OF THE JUGULAR FORAMEN

This paper examines the proposed association of bilateral asymmetry of the jugular foramen as an indicator of handedness observable from cranial morphology. The jugular foramina of 54 subjects were observed for size asymmetry during routine autopsy procedures. Hand preference data were collected on each subject from family members. Of the 54 subjects, 47 were documented as being right-handed and 7 as being left-handed. These values approximate the average percentage of right-handed versus left-handed individuals from larger populations. Jugular foramen asymmetry was qualitatively identified for 36 subjects (66.7%) and was judged equivocal for the other 18 (33.3%). Of the 36 subjects exhibiting asymmetry, 28 (77.7%) showed positive correlation between the asymmetry direction and handedness. This moderate level of congruence, coupled with the result that 4 of the 7 left-handers exhibited dominant right-side foramina, casts doubt on the reliable use of jugular foramen asymmetry for estimating handedness.