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Published in: Brain Structure and Function 8/2017

Open Access 01-11-2017 | Original Article

Laterality of anterior temporal lobe repetitive transcranial magnetic stimulation determines the degree of disruption in picture naming

Authors: Anna M. Woollams, Lee J. Lindley, Gorana Pobric, Paul Hoffman

Published in: Brain Structure and Function | Issue 8/2017

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Abstract

The bilateral anterior temporal lobes play a key role in semantic representation. This is clearly demonstrated by the performance of patients with semantic dementia, a disorder characterised by a progressive and selective decline in semantic memory over all modalities as a result of anterior temporal atrophy. Although all patients exhibit a progressive decline in both single-word production and comprehension, those with greater atrophy to the left anterior temporal lobe show a stronger decline in word production than comprehension. This asymmetry has been attributed to the greater connectivity of the left anterior temporal lobe with left-lateralised speech production mechanisms. Virtual lesioning of the left ATL using offline repetitive transcranial magnetic stimulation (rTMS) has been shown to disrupt picture naming, but, the impact of right ATL rTMS is yet to be explored. We tested the prediction that disruption of picture naming in normal participants by rTMS should be greater for the left than the right ATL. We found a significant increase in picture naming latencies specifically for stimulation of the left ATL only. Neither left nor right ATL TMS slowed performance in a number naming control task. These results support the hypothesis that although both temporal lobes are part of a widespread semantic network in the human brain, the left anterior temporal lobe possesses a stronger connection to left-lateralised speech production areas than the right temporal lobe.
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Metadata
Title
Laterality of anterior temporal lobe repetitive transcranial magnetic stimulation determines the degree of disruption in picture naming
Authors
Anna M. Woollams
Lee J. Lindley
Gorana Pobric
Paul Hoffman
Publication date
01-11-2017
Publisher
Springer Berlin Heidelberg
Published in
Brain Structure and Function / Issue 8/2017
Print ISSN: 1863-2653
Electronic ISSN: 1863-2661
DOI
https://doi.org/10.1007/s00429-017-1430-2

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