TY - JOUR

T1 - Broca’s area involvement in abstract and concrete word acquisition: tDCS evidence

AU - Гнедых, Дарья Сергеевна

AU - Цветова, Диана Маратовна

AU - Мкртычян, Надежда Андреевна

AU - Благовещенский, Евгений Дмитриевич

AU - Костромина, Светлана Николаевна

AU - Штыров, Юрий Юрьевич

N1 - Publisher Copyright: © 2022 Elsevier Inc.

PY - 2022/7

Y1 - 2022/7

N2 - Broca's area in the left hemisphere of the human neocortex has been suggested as a major hub for acquisition, storage, and access of linguistic information, abstract words in particular. Direct causal evidence for the latter, however, is still scarce; filling this gap was the goal of the present study. Using transcranial direct current stimulation (tDCS) of Broca's region, we aimed to delineate the involvement of this area in abstract and concrete word acquisition. The experiment used a between-subject design and involved 15 min of anodal or cathodal tDCS over Broca's area, or a sham/placebo control condition. The stimulation procedure was followed by a contextual learning session, in which participants were exposed to new concrete and abstract words embedded into short five-sentence texts. Finally, a set of behavioural assessment tasks was run to assess the learning outcomes immediately after the training (Day 1) and with a 24-hour delay (Day 2). The results showed that participants recognised novel abstract words more accurately after both anodal and cathodal tDCS in comparison with the sham condition on Day 1, which was also accompanied by longer recognition times (presumably due to deeper lexico-semantic processing), supporting the role of Broca's region in acquisition of abstract semantics. They were also more successful when recalling concrete words after cathodal tDCS, which indicates a degree of Broca's area involvement in forming memory circuits for concrete words as well. A decrease in the accuracy of recall of word forms and their meanings, as well as in recognition, was observed for all stimulation groups and both types of semantics on Day 2. The results suggest that both anodal and cathodal tDCS of Broca's area improves immediate contextual learning of novel vocabulary, predominantly affecting abstract semantics.

AB - Broca's area in the left hemisphere of the human neocortex has been suggested as a major hub for acquisition, storage, and access of linguistic information, abstract words in particular. Direct causal evidence for the latter, however, is still scarce; filling this gap was the goal of the present study. Using transcranial direct current stimulation (tDCS) of Broca's region, we aimed to delineate the involvement of this area in abstract and concrete word acquisition. The experiment used a between-subject design and involved 15 min of anodal or cathodal tDCS over Broca's area, or a sham/placebo control condition. The stimulation procedure was followed by a contextual learning session, in which participants were exposed to new concrete and abstract words embedded into short five-sentence texts. Finally, a set of behavioural assessment tasks was run to assess the learning outcomes immediately after the training (Day 1) and with a 24-hour delay (Day 2). The results showed that participants recognised novel abstract words more accurately after both anodal and cathodal tDCS in comparison with the sham condition on Day 1, which was also accompanied by longer recognition times (presumably due to deeper lexico-semantic processing), supporting the role of Broca's region in acquisition of abstract semantics. They were also more successful when recalling concrete words after cathodal tDCS, which indicates a degree of Broca's area involvement in forming memory circuits for concrete words as well. A decrease in the accuracy of recall of word forms and their meanings, as well as in recognition, was observed for all stimulation groups and both types of semantics on Day 2. The results suggest that both anodal and cathodal tDCS of Broca's area improves immediate contextual learning of novel vocabulary, predominantly affecting abstract semantics.

KW - Abstract concepts

KW - Brain

KW - Broca's area

KW - Concrete concepts

KW - Cortex

KW - Language

KW - Learning

KW - Left inferior-frontal gyrus (IFG)

KW - Non-invasive brain stimulation (NIBS)

KW - Semantics

KW - Transcranial direct current stimulation (tDCS)

KW - Word acquisition

UR - http://www.scopus.com/inward/record.url?scp=85129723892&partnerID=8YFLogxK

UR - https://www.mendeley.com/catalogue/e8bd1224-0ed8-3d4f-9335-c270aa5baf20/

U2 - 10.1016/j.nlm.2022.107622

DO - 10.1016/j.nlm.2022.107622

M3 - Article

VL - 192

JO - Neurobiology of Learning and Memory

JF - Neurobiology of Learning and Memory

SN - 1074-7427

M1 - 107622

ER -