Alzheimer's disease and implicit memory

Abstract

-Specific neuropsychiatric disorders, such as Alzheimer's disease (AD) affect some forms of memory while leaving others relatively intact. In this review, we investigate particularities of the relationship between explicit and implicit memories in AD. It was found that implicit memory is preserved in AD, irrespective of the task used; in other words, there was not interference from explicit memory. In addition, it was verified that is possible through implicit memory compensatory strategies such as, activities of daily living (ADL) to compensate for the explicit memory deficits. In this sense, cognitive rehabilitation (CR) demonstrates reasonable results in the process of compensation of explicit memory deficits. Concluding, the decline in explicit memory suggests that both systems are functionally independent even if the other is compromised. We expect that when explicit memory system is not involved in competition with the implicit system, the final effect of learning is better, because all of the implicit memory capacity is engaged in learning and not in competition with the explicit system. Key WoRDS: activities of daily living, Alzheimer's disease, cognitive rehabilitation, implicit memory. Doença de Alzheimer e memória implícitaResumo -Distúrbios neuropsiquiátricos específicos, tais como a doença de Alzheimer (DA), podem afetar algumas formas de memória enquanto deixam outros relativamente intactos. Nesta revisão, nós investigamos particularidades da relação entre as memórias explicita e implícita na DA. Foi verificado que a memória é preservada na DA, independente da tarefa usada; ou seja, não ocorre interferência da memória explícita. Além disso, foi verificado que é possível através de estratégias compensatórias de memória implícita, tais como, atividades da vida diária (AVD) compensar os déficits da memória explícita. Neste sentido, a reabilitação cognitiva (RC) demonstra resultados razoáveis no processo de compensação dos déficits da memória explicita. Concluindo, a queda na memória explícita sugere que ambos os sistemas são funcionalmente independentes mesmo que outro esteja comprometido. esperamos que quando o sistema de memória explícita não está envolvido em competição com o sistema implícito, o efeito final de aprendizagem é melhor, porque toda a capacidade da memória implícita está engajada na aprendizagem e não na competição com o sistema explícito. PALAVRAS-ChAVe: atividades da vida diária, doença de Alzheimer, memória implícita, reabilitação cognitiva.

Lexical Priming in Alzheimer's Disease and Aphasia

“…Besides, similar results have been reported previously [38,40,41,42,43,44,45,46,47,48]. However, our results concerning AD are not concordant with those of certain other studies [31,33,34,35,36,37].…”

“…Some investigators have reported a priming deficit in AD [30,31,32,33,34,35,36,37], whereas others have found no differences in priming effects between patients with AD and normal control participants [38,39,40,41,42,43,44,45,46,47,48]. Thus, Fleischman and Gabrieli [29] found that 65% of AD studies reported that priming was normal.…”

Semantic knowledge of newly coined words in mild cognitive impairment and Alzheimer’s disease

“…The context use task has already been shown to be easy enough to remain unaffected by age in healthy 20-to-79-year old adults (Thomas-Anterion et al, 2009), and implicit memory is known to be less affected by normal ageing than explicit memory (Brooks et al, 2001). Similarly, in our study, the preservation of the patients' performance in this task could reflect relatively spared implicit memory processing in MCI and AD (Fleischman, 2007;Machado et al, 2009), despite the onset of semantic impairments at the prodromal stage of AD. Therefore, difference of performance between the MCQ and the context use subtest as observed in the two groups of patients (but not in healthy seniors) may be induced by increased dissociation between explicit and implicit semantic memory skills in both MCI and AD.…”

“…Similarly, implicit memory appears to be spared in MCI patients (LaVoie & Faulkner, 2008). In AD, implicit memory is also relatively preserved as compared with the disproportionate decline in explicit memory (for a review, see Machado et al, 2009). Accordingly, the assessment of explicit and implicit abilities was argued to provide early signs of neurological disease (Fleischman, 2007).…”

Improving Dementia Care Through Behavioral Interventions

“…Second, people with dementia retain the ability to form implicit memories, which are formed through associative learning (so-called "stimulus-response" mechanisms) and thus do not require higher-order cognitive processing [14]. Having direct caregivers identify pleasant events and incorporate them into the daily routine of people with dementia may help to diminish some of the negative reactions (frustration or fear) that people with dementia may develop if they associate caregivers only with stimuli that are unpleasant, such as bathing or dressing experiences that do not take into account the cognitive level of the person with dementia.…”