title: Bihemispheric tDCS enhances language recovery but does not alter BDNF levels in chronic aphasic patients.
abstract: OBJECTIVE
  Several studies have shown that transcranial direct current stimulation (tDCS) is a useful tool to enhance language recovery in aphasia. It has also been suggested that modulation of the neurotrophin brain-derived neurotrophic factor (BDNF) might be part of the mechanisms involved in tDCS effects on synaptic connectivity. However, all language studies have previously investigated the effects using unihemispheric stimulation. The purpose of the present study is to investigate the role of bihemispheric tDCS on language recovery and BDNF serum levels.
  
  
  METHODS
  Seven aphasic persons underwent an intensive language therapy in two different conditions: real bihemispheric stimulation over the left and right Broca's areas and a sham condition.
  
  
  RESULTS
  After the stimulation, patients exibited a significant recovery in three language tasks (picture description, noun and verb naming) compared to the sham condition which persisted in the follow-up session. No significant differences were found in BDNF serum levels after tDCS stimulation and in the follow-up session. However, a significant positive correlation was present for the real stimulation condition between percent changes in BDNF levels and in the verb naming task.
  
  
  CONCLUSIONS
  The data suggest that this novel approach may potentiate the recovery of language in chronic aphasia. They also emphasize the importance to further investigate the role of possible biomarkers associated with tDCS treatment response in language recovery.
authors.affiliation: Facoltà di Medicina, Università Politecnica Marche, Ancona, Italy IRCCS Fondazione Santa Lucia, Roma, Italy.
authors.forename: Paola
authors.initials: P
authors.lastname: Marangolo
authors.affiliation: IRCCS Fondazione Santa Lucia, Roma, Italy.
authors.forename: Valentina
authors.initials: V
authors.lastname: Fiori
authors.affiliation: IRCCS Fondazione Santa Lucia, Roma, Italy Dipartimento di Medicina dei Sistemi, Università degli studi di Roma "Tor Vergata", Roma, Italy.
authors.forename: Francesca
authors.initials: F
authors.lastname: Gelfo
authors.affiliation: IRCCS Fondazione Santa Lucia, Roma, Italy.
authors.forename: Jacob
authors.initials: J
authors.lastname: Shofany
authors.affiliation: IRCCS Fondazione Santa Lucia, Roma, Italy.
authors.forename: Carmelina
authors.initials: C
authors.lastname: Razzano
authors.affiliation: IRCCS Fondazione Santa Lucia, Roma, Italy Dipartimento di Medicina dei Sistemi, Università degli studi di Roma "Tor Vergata", Roma, Italy.
authors.forename: Carlo
authors.initials: C
authors.lastname: Caltagirone
authors.affiliation: IRCCS Fondazione Santa Lucia, Roma, Italy.
authors.forename: Francesco
authors.initials: F
authors.lastname: Angelucci
mesh_terms: D000368:Aged; D001037:Aphasia / Q000097:blood / Q000209:etiology / Q000628:therapy*; D019208:Brain-Derived Neurotrophic Factor / Q000097:blood*; D002908:Chronic Disease; D004599:Electric Stimulation Therapy; D005260:Female; D006801:Humans; D007802:Language; D008297:Male; D008875:Middle Aged; D009483:Neuropsychological Tests; D011930:Reaction Time; D020127:Recovery of Function / Q000502:physiology; D020521:Stroke / Q000150:complications
chemical_list: D019208:Brain-Derived Neurotrophic Factor
keywords: Aphasia; BDNF; Broca's area; bihemispheric tDCS; language recovery