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Two studies explored the stability of art preference in patients with Alzheimer's disease and age-matched control participants. Preferences for three different styles of paintings, displayed on art postcards, were examined over two sessions. Preference for specific paintings differed among individuals but AD and non-AD groups maintained about the same stability in terms of preference judgments across two weeks, even though the AD patients did not have explicit memory for the paintings. We conclude that aesthetic responses can be preserved in the face of cognitive decline. This should encourage caregivers and family to engage in arts appreciation activities with patients, and reinforces the validity of a preference response as a dependent measure in testing paradigms.

The association between epilepsy and amnesia is studied in patient J.T. who presented with a very unusual pattern of memory loss with retention of information for hours to days but rapid forgetting of information that exceeded this time frame. J.T.'s unusual memory profile was studied with several tests administered over week-long intervals of time. There was evidence that his retention decreased in conjunction with increased seizures. During a trial of paraldehyde, a decrease in seizure frequency was associated with enhanced memory. J.T.'s memory problem was unlike that described in prototypical cases of amnesia. His day-long retention of new information alongside his absolute loss of that information days later is consistent with the idea that consolidation is a process that occurs over lengthy periods of time.

We studied perception in three patients with prosopagnosia of childhood onset. All had trouble with other ‘within-category’ judgments. All were deficient on face matching tests and severely impaired on tests of perception of the spatial relations of facial features and abstract designs, indicating a deficit in the encoding of coordinate relationships, similar to adult-onset prosopagnosia with lesions of the fusiform face area. Two had difficulty perceiving feature colour, which correlated with reduced luminance sensitivity. In contrast to adult-onset patients, saturation discrimination was spared in two and spatial resolution impaired in two. Curvature discrimination was relatively spared. Contrast sensitivity showed variable reductions at different spatial frequencies. We conclude that developmental prosopagnosia is similar to the adult-onset form in encoding deficits for the spatial arrangement of facial elements. Deficits in luminance perception and spatial resolution are more associated with defective encoding for basic object-level recognition, as shown on tests of object and spatial perception.

This paper explores potential cognitive deficits underlying confabulation of a patient, G.S., following an anterior communicating artery aneurysm. G.S.’s performance on tasks assessing memory for temporal duration, temporal order, and speaker identification is examined as is his recollection of autobiographical events. We compare G.S. with three nonconfabulating patients matched with him for age, education, and neuropsychological measures of memory and frontal deficits and with three age- and education-matched control subjects. Like frontal control patients, G.S. underestimated temporal durations and showed poor source monitoring (speaker identification). In addition, G.S. showed an even more pronounced deficit in recall of autobiographical memories and relatively more detailed reports of laboratory-induced memories for imagined events. We suggest that this configuration of deficits rather than any single factor accounts for G.S.’s tendency to confabulate.

The implicit memory ability of a patient (S.S.) with severe amnesia due to encephalitis was assessed using five independent paradigms: Perceptual priming with real words and pseudowords; Word-stem completion with and without contextual cues; Word-stem completion following presentation of high- vs. low-frequency words; Biasing of the spelling of ambiguous (homophonic) words; and Conceptual priming. On the tasks in which previously acquired knowledge could potentially be activated by a prime (e.g., perceptual priming with real words), both S.S. and the Korsakoff patients performed on a normal level. However, when new learning or new associations had to be formed prior to implicit memory testing (e.g., perceptual priming of pseudowords or contextual word-stem completion), S.S.'s implicit memory performance was superior to Korsakoff amnesics. These results suggested that new learning differentially affects the priming abilities of S.S. and alcoholic Korsakoff patients. Since S.S.'s amnesia is as severe as Korsakoff patients, it was also concluded that severity of amnesia is clearly not the sole determinant of priming capacity; etiology may be equally important.