Differential impact of continuous theta-burst stimulation over left and right DLPFC on planning

Autor: Annekathrein Frenkel, Cornelius Weiller, Benjamin Rahm, C. H. Läppchen, Rüdiger Lange, Josef M. Unterrainer, Christoph P. Kaller, Katharina Heinze
Rok vydání: 2011
Předmět:
Zdroj: Hum Brain Mapp
ISSN: 1065-9471
DOI: 10.1002/hbm.21423
Popis: Most neuroimaging studies on planning report bilateral activations of the dorsolateral prefron- tal cortex (dlPFC). Recently, these concurrent activations of left and right dlPFC have been shown to dou- ble dissociate with different cognitive demands imposed by the planning task: Higher demands on the extraction of task-relevant information led to stronger activation in left dlPFC, whereas higher demands on the integration of interdependent information into a coherent action sequence entailed stronger activa- tion of right dlPFC. Here, we used continuous theta-burst stimulation (cTBS) to investigate the supposed causal structure-function mapping underlying this double dissociation. Two groups of healthy subjects (left-lateralized stimulation, n ¼ 26; right-lateralized stimulation, n ¼ 26) were tested within-subject on a variant of the Tower of London task following either real cTBS over dlPFC or sham stimulation over pos- terior parietal cortex. Results revealed that, irrespective of specific task demands, cTBS over left and right dlPFC was associated with a global decrease and increase, respectively, in initial planning times com- pared to sham stimulation. Moreover, no interaction between task demands and stimulation type (real vs. sham) and/or stimulation side (left vs. right hemisphere) were found. Together, against expectations from previous neuroimaging data, lateralized cTBS did not lead to planning-parameter specific changes in performance, but instead revealed a global asymmetric pattern of faster versus slower task processing after left versus right cTBS. This global asymmetry in the absence of any task-parameter specific impact of cTBS suggests that different levels of information processing may span colocalized, but independent axes of functional lateralization in the dlPFC. Hum Brain Mapp 00:000-000, 2011. V C 2011 Wiley Periodicals, Inc.
Databáze: OpenAIRE