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This study investigated the performance of left- (LBD) and right-brain-damaged (RBD) patients in recognizing personal names under different conditions of associative priming. Subjects performed speeded familiarity decisions for names of famous and unfamiliar persons. These target names were preceded by primes, either faces or names, which could be neutral, related (e.g. Gorbachev-Jelzin), or unrelated (e.g. Travolta-Carter). Overall impairments in name recognition were observed in both patient groups relative to controls but were more severe in LBD than in RBD patients. This suggests that, contrary to previous hypotheses, the recognition of personal names is more dependent on left hemisphere functioning. In controls and LBD patients, associative priming effects did not differ significantly between face and name primes. In RBD patients, however, associative priming from names was larger than priming from faces. This specificity of priming effects for names in RBD patients was tentatively related to their impairments in face recognition.

Covert face recognition was investigated in a patient with prosopagnosia without object agnosia. This patient performed well in various face processing tasks like expression analysis and feature processing and had relatively preserved semantic knowledge about persons, but was slightly impaired in the visual matching of unfamiliar faces. In face-name paired-associate relearning task, covert face recognition was demonstrated to be above-chance. However, as this task cannot be meaningfully applied to control subjects, results do not necessarily indicate that the degree of covert face recognition is normal. In fact, in contrast to control subjects, the patient showed significantly reduced associative priming of names by face primes as compared to name primes, suggesting a quantitative reduction of covert face recognition. It is argued that these results support the view that overt and covert face recognition are brought about by the same functional system (Farah, O'Reilly and Vecera, 1993).

A neglected topic in metamemory research is the ability of subjects to predict their own recognition performance for faces. We investigated whether subjects can make such judgments of learning (JOL) for unfamiliar faces and whether JOLs relate to facial distinctiveness, a powerful determinant of face recognition. One group of subjects made JOLs, and a second group rated the same faces for distinctiveness; subsequently, both groups tried to recognize these faces among new faces. There was significant prospective metamemory for faces that appeared to be based on facial distinctiveness. Both prospective metamemory and distinctiveness ratings related to long-lasting effects in event-related brain potentials (ERPs), closely resembling an ERP component that predicted face recognition. Therefore, the brain processes underlying JOLs, distinctiveness, and recognition memory for faces appear to be intimately related.

This study demonstrates that operant conditioning may increase the P300 component of the event-related potential above a level obtained without contingent training. An experimental group of subjects was rewarded for producing large P300 amplitudes and was compared with a yoked control group which was rewarded on a random basis. During training the experimental subjects increased both the amplitude of the P300 and of a subsequent frontal negative slow wave relative to the control group. These training effects were independent of prestimulus potential shifts and occurred likewise for target and nontarget stimuli.