Alterations in resolution of temporal order after cerebral injury in man

Forty patients with penetrating head injuries and a control group of 12 subjects were tested on their ability to resolve the relative orders of repeated sequences of sounds. The sound sequences differed in the extent to which language-specific analysis of the signal was required. The findings indicated a language-independent deficit in the ability to resolve the order of repeated sound sequences after penetrating lesions of the left cerebral hemisphere. This deficit provides additional support for the claim that the left hemisphere is more competent than the right in discriminating fine time differences and that this facility may underlie in part the left hemisphere's specialization for language.