Is an intact hippocampus necessary for answering 3â¯×â¯3? - Evidence from Alzheimer's disease.
Brain Cogn
; 134: 1-8, 2019 08.
Article
em En
| MEDLINE
| ID: mdl-31054405
ABSTRACT
Recent evidence has suggested that the hippocampus supports learning and retrieval of arithmetic facts during childhood and adolescence. Whether the hippocampus is also involved in retrieving overlearned arithmetic facts (such as 3â¯×â¯5â¯=â¯15) during adult age is open for investigation. In this study, we assessed whether patients with hippocampal atrophy due to Alzheimer's disease (AD) are still able to retrieve overlearned arithmetic facts from memory. Sixteen patients (nâ¯=â¯13 with AD, nâ¯=â¯3 with Mild Cognitive Impairment - MCI) were evaluated using standard radiological, neurological, and neuropsychological test procedures. We adopted a multiple single-case analysis in order to acknowledge possible dissociations between hippocampal degeneration and intact arithmetic fact retrieval. All patients performed a neuropsychological screening battery assessing episodic memory as well as arithmetic processing, and underwent a 3-Tesla MRI procedure. A morphometric analysis comprising estimation of both cortical thickness and hippocampal volume, which also included a subfield analysis, was conducted. All patients had marked hippocampal atrophy (bilateral nâ¯=â¯15, unilateral nâ¯=â¯1) in comparison to healthy matched controls and showed deficits in episodic memory (delayed recall). However, 13 out of 16 patients performed in the average range of standardised norms during retrieval of overlearned arithmetic facts (i.e. multiplication tables). Our results suggest that intact retrieval of consolidated arithmetic facts from memory does not depend on the integrity of the hippocampus. This is in line with the view that the hippocampus plays a dynamic and time-limited role in arithmetic processing. While the hippocampus seems to be necessary for learning and consolidating new arithmetic facts in memory, it might not be critically involved in retrieving arithmetic facts when these are well consolidated in memory.
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Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Lobo Temporal
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Doença de Alzheimer
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Memória Episódica
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Hipocampo
Limite:
Aged
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Aged80
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Female
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Humans
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Male
Idioma:
En
Revista:
Brain Cogn
Ano de publicação:
2019
Tipo de documento:
Article
País de afiliação:
Áustria