Nonverbal Recognition Memory Research Articles

Signal-Detection Analysis of Nonverbal Recognition Memory in Dementia

A signal-detection analysis was applied to performance on two non-verbal recognition memory tasks for 21 subjects with presumed dementia of the Alzheimer type, 19 subjects with presumed multi-infarct dementia, and 19 elderly depressed subjects. Performance was best for the depressed and worst for the Alzheimer subjects. Response bias did not differ significantly among groups. Within the depressed group, more impaired and older subjects were more conservative on one test. Correlations suggested that the sensitivity and response-bias measures may depend on the type of material used and so have limited generality.

SIGNAL-DETECTION ANALYSIS OF NONVERBAL RECOGNITION MEMORY IN DEMENTIA

A signal-detection analysis was applied to performance on two nonverbal recognition memory tasks for 21 subjects with presumed dementia of the Alzheimer type, 19 subjects with presumed multi-infarct dementia, and 19 elderly depressed subjects. Performance was best for the depressed and worst for the Alzheimer subjects. Response bias did not differ significantly among groups. Within the depressed group, more impaired and older subjects were more conservative on one test. Correlations suggested that the sensitivity and response-bias measures may depend on the type of material used and so have limited generality.

Verbal and nonverbal recognition memory in aphasic and nonaphasic stroke patients

The ability to retain lists of verbal and nonverbalizable items across recurrent recognition tasks was tested in three groups: (1) stroke patients with a left-brain lesion and aphasia, (2) stroke patients with a right-brain lesion and left hemiplegia, and (3) nonneurologically impaired outpatients. As determined with signal detection measures, aphasics were deficient in discriminating words that were to be remembered from those that were not; their recognition of nonverbal visual (geometric art) or auditory (bird calls) patterns, however, was unimpaired. Left hemiplegics showed the opposite pattern. After a long-term interval (<10 min), correct recognition of words was diminished in all groups whereas recognition of visual patterns increased. Both groups of stroke patients adopted material-specific decision criteria which in part accounted for the dissociation of verbal and nonverbal recognition memory by laterality of lesion. Item analysis indicated that aphasics' verbal memory difficulties were affected by acoustic-semantic confusion of list words.

Inconstant nonverbal recognition memory in Korsakoff patients and controls

Eleven alcoholic Korsakoff patients, 12 alcoholic controls, and 12 volunteers were asked to remember complex nonverbal items (8 bird calls and 8 coloured geometric art patterns) across each of 3 auditory and 3 visual tests of recurrent recognition. Item-by-item analyses of correct recognitions indicated that Korsakoff patients forgot many items, yet recovered other to-be-remembered items from one test to the next. Influenced by decision uncertainty, the recognition memory of Korsakoff patients (as estimated in measures derived from Signal Detection Theory) declined across tests in the auditory task, that of chronic alcoholics only in the visual task. Neither the item fluctuation nor the low decision criteria adopted by Korsakoff patients were found to be task-specific.