Sham protocols for transcranial direct current stimulation using high-definition electrodes

Richardson, Jessica D.; Fillmore, Paul; Datta, Abhishek; Truong, Dennis Q.; Hudspeth, Sarah Grace; Bikson, Marom; Fridriksson, Julius

doi:10.1016/j.brs.2014.01.031

Cited by 1 publication

(1 citation statement)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Future studies may use a more focal stimulation technique, such as TMS, to verify the present results. Yet another way to control the outcomes in future neuromodulation studies could be to use double-blind experimental designs 75 , 76 .…”

Section: Discussionmentioning

confidence: 99%

Acquisition of concrete and abstract words is modulated by tDCS of Wernicke’s area

Kurmakaeva

Blagovechtchenski

Gnedykh

et al. 2021

Sci Rep

View full text Add to dashboard Cite

Previous behavioural and neuroimaging research suggested distinct cortical systems involved in processing abstract and concrete semantics; however, there is a dearth of causal evidence to support this. To address this, we applied anodal, cathodal, or sham (placebo) tDCS over Wernicke’s area before a session of contextual learning of novel concrete and abstract words (n = 10 each), presented five times in short stories. Learning effects were assessed at lexical and semantic levels immediately after the training and, to attest any consolidation effects of overnight sleep, on the next day. We observed successful learning of all items immediately after the session, with decreased performance in Day 2 assessment. Importantly, the results differed between stimulation conditions and tasks. Whereas the accuracy of semantic judgement for abstract words was significantly lower in the sham and anodal groups on Day 2 vs. Day 1, no significant performance drop was observed in the cathodal group. Similarly, the cathodal group showed no significant overnight performance reduction in the free recall task for either of the stimuli, unlike the other two groups. Furthermore, between-group analysis showed an overall better performance of both tDCS groups over the sham group, particularly expressed for abstract semantics and cathodal stimulation. In sum, the results suggest overlapping but diverging brain mechanisms for concrete and abstract semantics and indicate a larger degree of involvement of core language areas in storing abstract knowledge. Furthermore, they demonstrate a possiblity to improve learning outcomes using neuromodulatory techniques.

show abstract

Section: Discussionmentioning

confidence: 99%