Acetylcholine modulates human working memory and subsequent familiarity based recognition via alpha oscillations.
Neuroimage
; 137: 61-69, 2016 Aug 15.
Article
en En
| MEDLINE
| ID: mdl-27222217
ABSTRACT
Working memory (WM) can be defined as the ability to maintain and process physically absent information for a short period of time. This vital cognitive function has been related to cholinergic neuromodulation and, in independent work, to theta (4-8Hz) and alpha (9-14Hz) band oscillations. However, the relationship between both aspects remains unclear. To fill this apparent gap, we used electroencephalography (EEG) and a within-subject design in healthy humans who either received the acetylcholinesterase inhibitor galantamine (8mg) or a placebo before they performed a Sternberg WM paradigm. Here, sequences of sample images were memorized for a delay of 5s in three different load conditions (two, four or six items). On the next day, long-term memory (LTM) for the images was tested according to a remember/know paradigm. As a main finding, we can show that both theta and alpha oscillations scale during WM maintenance as a function of WM load; this resembles the typical performance decrease. Importantly, cholinergic stimulation via galantamine administration slowed down retrieval speed during WM and reduced associated alpha but not theta power, suggesting a functional relationship between alpha oscillations and WM performance. At LTM, this pattern was accompanied by impaired familiarity based recognition. These findings show that stimulating the healthy cholinergic system impairs WM and subsequent recognition, which is in line with the notion of a quadratic relationship between acetylcholine levels and cognitive functions. Moreover, our data provide empirical evidence for a specific role of alpha oscillations in acetylcholine dependent WM and associated LTM formation.
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Encéfalo
/
Acetilcolina
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Reconocimiento en Psicología
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Ritmo alfa
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Memoria a Largo Plazo
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Memoria a Corto Plazo
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Plasticidad Neuronal
Tipo de estudio:
Clinical_trials
Límite:
Adult
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Female
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Humans
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Male
Idioma:
En
Revista:
Neuroimage
Asunto de la revista:
DIAGNOSTICO POR IMAGEM
Año:
2016
Tipo del documento:
Article
País de afiliación:
Alemania