2 research outputs found
Something to talk about: enhancement of linguistic cohesion through tdCS in chronic non fluent aphasia
Several studies have shown that the modulation of cortical activity through transcranial direct current
stimulation (tDCS) enhances naming performance in persons with aphasia. In this study, we investigated
the potential effects of tDCS in improving spontaneous speech and the ability to use connective words to
establish cohesion among adjacent utterances in a group of eight participants with chronic non \ue000uent
aphasia. They were administered \ue001ve short videoclips representing everyday life contexts and two
picture description tasks. Three videoclips were used to elicit spontaneous conversation during the
treatment, while the remaining tasks were presented to the patients only before and after the therapy.
Patients were required to talk about each videoclip, with the help of a therapist, while they were treated
with tDCS (20 min, 1 mA) over the left hemisphere in three different conditions: anodic tDCS over the
Broca's area, anodic tDCS over the Wernicke's area and a sham condition. Each experimental condition
was performed for ten consecutive daily sessions with 14 days of intersession interval. Only after Broca's
stimulation, patients showed a greater improvement in producing words that enhanced the cohesion of
their speech samples (i.e., pronouns, ellipses, word repetitions, conjunctions). Bene\ue001cial effects of the
stimulation were generalized also to contexts presented to the patients at the beginning and at the end of
the therapy sessions. Our data further con\ue001rm the key role of the left inferior frontal gyrus in binding
words into a coherent speech. We believe that positive tDCS effects may be further extended to different
linguistic domains, useful to promote language recovery