Interaction between a verbal working memory network and the medial temporal lobe.
The irrelevant speech effect illustrates that sounds that are irrelevant to a visually presented short-term memory task still interfere with neuronal function. In the present study we explore the functional and effective connectivity of such interference. The functional connectivity analysis suggested an interaction between the level of irrelevant speech and the correlation between in particular the left superior temporal region, associated with verbal working memory, and the left medial temporal lobe. Based on this psycho-physiological interaction, and to broaden the understanding of this result, we performed a network analysis, using a simple network model for verbal working memory, to analyze its interaction with the medial temporal lobe memory system. The results showed dissociations in terms of network interactions between frontal as well as parietal and temporal areas in relation to the medial temporal lobe. The results of the present study suggest that a transition from phonological loop processing towards an engagement of episodic processing might take place during the processing of interfering irrelevant sounds. We speculate that, in response to the irrelevant sounds, this reflects a dynamic shift in processing as suggested by a closer interaction between a verbal working memory system and the medial temporal lobe memory system.
Petersson
Karl Magnus
KM
F.C. Donders Centre for Cognitive Neuroimaging, Radboud University Nijmegen, The Netherlands. karl.magnus.petersson@fcdonders.ru.nl
Gisselgård
Jens
J
Gretzer
Monica
M
Ingvar
Martin
M
D006801:Humans; D008297:Male; D008568:Memory / Q000502:physiology*; D009415:Nerve Net / Q000502:physiology*; D013060:Speech / Q000502:physiology*; D013702:Temporal Lobe / Q000502:physiology*