Whereas memory deficits are the hallmark of dementia in early stages, other aspects of information processing, such as attention and encoding, have been reported to be very soon altered. Looking for neuropsychological markers of DAT, we recently identified some aspects of memory deficits as capable of distinguishing DAT from other forms of dementia at satisfactory level of accuracy. In the present study we took into account 'selective attention' - i.e.: the ability to maintain focus on salient features while suppressing irrelevant ones -, that is one of the critical encoding mechanisms on which all further cognitive functions depend. We studied performance of 68 DAT and 40 MID demented patients - accurately matched for the overall severity of dementia -, on a battery of cognitive tasks. The battery included two 'timed' cancellation tasks involving visual-spatial exploration and psychomotor speed, but differently demanding in terms of selective attention skills. DAT patients performed significantly worse than MID on several memory measures (immediate and delayed recall, number of 'false alarms' in delayed recognition of Rey's Auditory Verbal Learning Test; Immediate Recognition of Abstract Visual Patterns) and on Verbal Fluency. The two cancellation tasks did not differentiate the two dementia groups considering overall quantitative scores. However the qualitative patterns of errors were quite different, owing to the remarkable prevalence of 'false alarms' in DAT patients' performance on the task more demanding in terms of selective attention skills.
|Number of pages||1|
|Journal||Italian Journal of Neurological Sciences|
|Publication status||Published - 1997|
ASJC Scopus subject areas
- Clinical Neurology