Skin conductance responses (SCRs) were recorded in a patient with frontal lobe damage and in normal control subjects while attempting recognition of famous and unfamiliar faces. The patient had more overt false recognition errors and misidentifications of unfamiliar faces than the controls, while, similar to controls, he showed accurate covert autonomic discrimination of familiar from unfamiliar faces. Overt and covert forms of memory for face recognition are dissociable following frontal lobe damage. Memory distortions are related to a sense of familiarity, or deja vu, that have a resemblance to previously seen faces. The false recognition results from breakdown of frontal memory retrieval mechanisms involved in correctly attributing familiar faces to the appropriate source. 
COMMENT. False recognition and confabulation of memory and misattributions of familiarity with faces are characteristics of frontal lobe dysfunction. Overt or explicit and covert implicit measures of memory are dissociable. Verbal and autonomic measures of recognition are poorly correlated in patients with agnosia and amnesia.
Prosopagnosia or agnosia for faces may be found in lesions of the posterior portion of the minor hemisphere, and unlike those with frontal lobe damage, patients fail to recognize familiar individuals, insisting that all faces are unfamiliar. Prosopagnosia is associated with contralateral visual field defect.