The effects of closed head injury upon intrusions and confusions in free recall

Richardson, John T. E. (1984). The effects of closed head injury upon intrusions and confusions in free recall. Cortex, 20(3) pp. 413–420.

DOI: https://doi.org/10.1016/S0010-9452(84)80009-X

Abstract

Previous research suggests that closed head injury impairs the use of semantic encoding in human memory, and especially the use of mental imagery. An analysis of intrusion and confusion errors in immediate free recall was carried out to provide further evidence on the effects on head injury upon different categories of encoding operation. There was no sign of any effect of closed head injury upon the incidence of either phonemically related or semantically related confusion errors, nor upon the overall incidence of intrusion errors from previous lists. However, the control subjects demonstrated a strong tendency to produce intrusion errors of similar concreteness to the current list, a tendency which was totally absent in the case of the head-injured subjects. It is suggested that the persistent effects of closed head injury upon human memory may be attributable to a failure to attend to the image-evoking quality of the stimulus material.