Recognition of affective and noncanonical linguistic facial expressions in hearing and deaf subjects

This study explores the use of two types of facial expressions, linguistic and affective, in a lateralized recognition accuracy test with hearing and deaf subjects. The linguistic expressions represent unfamiliar facial expression for the hearing subjects whereas they serve as meaningful linguistic emblems for deaf signers. Hearing subjects showed left visual field advantages for both types of signals while deaf subjects' visual field asymmetries were greatly influenced by the order of presentation. The results suggest that for hearing persons, the right hemisphere may predominate in the recognition of all forms of facial expression. For deaf signers, hemispheric specialization for the processing of facial signals may be influenced by the differences these signals serve in this population. The use of noncanonical facial signals in laterality paradigms is encouraged as it provides an additional avenue of exploration into the underlying determinants of hemispheric specialization for recognition of facial expression.