title: Something to talk about: enhancement of linguistic cohesion through tdCS in chronic non fluent aphasia.
abstract: 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 fluent aphasia. They were administered five 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). Beneficial 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 confirm 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.
authors: Facoltà di Medicina, Università Politecnica Marche, Ancona, Italy; IRCCS Fondazione Santa Lucia, Roma, Italy. Electronic address: p.marangolo@univpm.it.
authors: Paola
authors: P
authors: Marangolo
authors: IRCCS Fondazione Santa Lucia, Roma, Italy.
authors: Valentina
authors: V
authors: Fiori
authors: IRCCS Fondazione Santa Lucia, Roma, Italy.
authors: Serena
authors: S
authors: Campana
authors: IRCCS Fondazione Santa Lucia, Roma, Italy.
authors: Maria Antonietta
authors: MA
authors: Calpagnano
authors: IRCCS Fondazione Santa Lucia, Roma, Italy.
authors: Carmelina
authors: C
authors: Razzano
authors: IRCCS Fondazione Santa Lucia, Roma, Italy; Università di Tor Vergata, Roma, Italy.
authors: Carlo
authors: C
authors: Caltagirone
authors: IRCCS Fondazione Santa Lucia, Roma, Italy; Dipartimento di Scienze Umane, Università di Udine, Udine, Italy. Electronic address: andrea.marini@uniud.it.
authors: Andrea
authors: A
authors: Marini
mesh_terms: D000328:Adult; D000368:Aged; D001039:Aphasia, Broca / Q000473:pathology / Q000628:therapy*; D001921:Brain / Q000473:pathology; D002908:Chronic Disease; D004599:Electric Stimulation Therapy / Q000379:methods; D005260:Female; D005625:Frontal Lobe / Q000473:pathology; D006801:Humans; D007808:Language Therapy; D008037:Linguistics; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009483:Neuropsychological Tests; D013060:Speech; D016896:Treatment Outcome
keywords: Aphasia rehabilitation; Brain stimulation; Broca's area; Cohesion; Left frontal gyrus; Pragmatics; tDCS