Verbal and spatial memory spans in Alzheimer's and multi-infarct dementia

Abstract

This study aimed to explore verbal and spatial memory spans in Alzheimer's (AD) and multi‐infarct (MID) demented patients. For this purpose, we administered the forward and backward versions of the Digit Span and of the Corsi test to 18 AD, 18 MID and 26 controls. Results revealed a normal forward verbal span but reduced backward verbal and forward and backward spatial spans in both demented groups. These data are discussed in the light of the Working Memory model. It is argued that the normal verbal forward span is sustained by a normally functioning Articulatory Loop. The deficient processing resources of the Central Executive, on the other side, are responsible for the reduced extension of the other memory spans. The possible anatomical substrate of short‐term memory impairment in dementia, as well as alternative interpretations of memory span performance in demented patients are discussed.

Investigating the autonomic nervous system and cognitive functions as potential mediators of an association between cardiovascular disease and driving performance

“…Without appropriate task difficulty, it may be possible for cardiac participants to perform similarly to their healthy counterparts. It is documented that populations susceptible to cognitive decrements can still perform to similar levels as healthy individuals on easy cognitive tasks (Archibald et Fisk, 2000;Carlesimo et al, 1994;Earles et al, 2004). However, when faced with more challenging cognitive tasks, individuals with cognitive decrements generally perform poorer than cognitively healthy individuals (Castel et al, 2009;de Frias et al, 2007;Ewen et al, 2012).…”

Domain-Specific Improvement of Cognition on Memantine in Patients with Alzheimer’s Disease Treated with Rivastigmine

“…Given the excellent test-retest stability of span tasks without retest improvement [43] , the increase of the digit span forward is a meaningful finding that probably explains the improvement in the memory subscore of the ADAS-cog. The verbal forward span indicates a normally functioning articulatory loop, while the reduced backward span results from deficient processing resources of the central executive [44] . From other studies it is known that the verbal span is least affected in dementia compared to backward or block spans [44] and that AD patients may not spontaneously engage central executive resources to reach their maximal span score [45] .…”

Working memory in early Alzheimer's disease: a neuropsychological review

“…mouthing an irrelevant word), which interferes with subvocal articulation by the ARM (Morris, 1994). (Grossi et al, 1993) 39 AD MILD (MMSE-21.4 (4.9)) Impaired 62 EC (Carlesimo et al, 1994) 18 AD MILD Impaired 18 MID (Global performance index) 26 EC (Trojano et al, 1994) 30 EC MILD (MMSE 22.6) Impaired 38 AD (Cherry et al, 1996) 49 …”

“…This involves encoding of visual stimuli, short term storage of spatial location and sequence order and maintenance of information over time (Fischer, 2001). As reviewed in Table 2, impairment on this task has been found in both mild and moderate AD groups compared to both young and elderly controls but not in MCI (Corkin, 1982;Orsini (Morris, 1984) 17 AD MOD Impaired 17 EC ('Moderate severe anterograde amnesia and moderately disorientated') (Martin et al, 1985) 14 AD MILD Intact 11 EC (WAIS, WMS) (Kopelman, 1985) 16 AD MILD-MOD Impaired 16 Korsakoff (NART, IQ, Wechsler logical memory) 16 EC (Morris, 1987a) 21 AD MILD Impaired 21 EC (WAIS and clinical evidence) (Becker, 1988) 71 AD MILD (MMSE 22.5 (5.2)) Impaired 89 EC (Spinnler et al, 1988) 29 AD MILD-MOD Impaired 42 YC (Psychometric assessment) 58 EC (Orsini et al, 1988) 51 AD MILD (n ¼ 24) Intact 30 EC MOD (n ¼ 27) Impaired (History, orientation, visual retention test, clinical judgement) (Lines et al, 1991) 16 AD MILD (n ¼ 8, MMSE 22 (20-26)) Intact 8 EC MOD (n ¼ 8, MMSE 11-19) Impaired (Hulme et al, 1993) 14 AD MILD Impaired 14 EC (relatively early stage of dementia, Clifton assessment procedure) (Carlesimo et al, 1994) 18 AD MILD Intact 18 MID (Global performance index) 26 EC (Hodges and Patterson, 1995) 52 AD MIN (n ¼ 17, MMSE 25.6 (1.8)) Intact 24 EC MILD (n ¼ 17, MMSE 20.9 (1.7)) Impaired MOD (n ¼ 18, MMSE 10 (4.6)) Impaired (Greene et al, 1995) et al., 1988;Spinnler et al, 1988;Sahgal et al, 1992;Grossi et al, 1993;Carlesimo et al, 1994;Trojano et al, 1994;Cherry et al, 1996). As the Corsi block tapping task requires both visuospatial storage and executive processing (temporal sequencing), the impairment seen in early AD, on both forward and backward spatial spans, has been interpreted as reflecting deficits in both the VSS and central executive (Carlesimo et al, 1994).…”

“…Subjects can be asked to recall the span sequence in reverse, referred to as the backward span. This is thought to require increased processing and therefore to involve the CES as well as the subsidiary system (Carlesimo et al, 1994;Cherry et al, 1996).…”