Clinical trial NCT02840370: Effect of Stimulation of the Prefrontal Cortex on Language Production in Aphasic Patients
Official title: Effect of Transcranial Direct Current Stimulation of the Prefrontal Cortex on Language Production in Aphasic Patients: a Multicentre Experimental Study With a Placebo-controlled and Double Blind Crossover Design
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: NA
Conditions: Aphasia
Keywords: transcranial direct current stimulation
aphasia
language production
prefrontal cortex
Lead sponsor: University of Fribourg
Sponsor class: OTHER
Collaborators: name: University Hospital, Geneva
name: Hôpital Cantonal de Fribourg
First posted: 2016-07-21
Enrollment: 19
Sex: ALL
Minimum age (years): 18
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Allocation: RANDOMIZED
Intervention model: CROSSOVER
Primary purpose: OTHER

Brief summary: The purpose of this study is to investigate whether transcranial direct current stimulation (tDCS) of the prefrontal cortex (PFC) influences lexical access and language production. The experimental paradigm will assess the impact of prefrontal stimulation by tDCS versus sham tDCS (S-tDCS) over the PFC of patients with chronic post-stroke aphasia during three language production tasks and a nonverbal executive functions task.

Detailed description: Background:

Language processing is a complex brain function supported by a large network, including domain-specific language areas as well as domain-general cognitive-control networks (Friederici \& Gierhan, 2013). Noninvasive brain stimulation, such as transcranial direct current stimulation (tDCS), is increasingly being used as a promising therapeutic tool for psychiatric and neurological diseases (Tortella et al., 2015; Flöel, 2014). In the language domain, several studies revealed that tDCS over languagespecific areas induces changes in cortical function that enhances the recovery of language abilities in patients with post-stroke aphasia (Torres, Drebing \& Hamilton, 2013; Monti et al., 2013). Beneficial effects of tDCS have also been found for stimulation over more domain-general cognitive control regions. Although research on non-invasive brain stimulation and aphasia reveals promising results, studies investigating the modulation of cognitive control-networks on lexical access are rare. Given the importance of a successful interplay between prefrontal and domain-specific language areas, possible therapeutic effects of tDCS over the prefrontal cortex (PFC) in aphasia can be of high value for rehabilitation and basic research.

Procedure:

A planned total of 30 patients will be included. In a first visit, the severity of aphasia, the medical history as well as inclusion/exclusion criteria will be evaluated. After this visit, patients will undergo two tDCS sessions (one tDCS and one S-tDCS session) with a one week interval between the sessions. Each session consists of an online (during stimulation) and an offline assessment (within 30 minutes after stimulation). Three language tasks and a nonverbal executive function task will be conducted online as well as offline in each of the two sessions (tDCS and S-tDCS).

Eligibility criteria: Inclusion Criteria:

* Chronic aphasia due to ischemic or haemorrhagic stroke (\> 6 months post-stroke)
* French as dominant language
* Right-handedness
* Left hemisphere lesion with intact bilateral PFC

Exclusion Criteria:

* Diagnosed dementia or psychiatric comorbidity
* Epileptic seizure within the last 12 months
* Metallic head implants
* Pacemaker
* Inability to understand procedures or insufficient language production abilities
* pregnancy
* strong headache on the days of the tDCS sessions
* consumption of alcohol and/or unprescribed drugs on the days of the tDCS sessions or on the day before

Primary outcomes:
measure: Language production
timeFrame: up to 30 min
Secondary outcomes:
measure: Nonverbal executive functions task
timeFrame: up to 30 min
Other outcomes:
Locations:
city: Fribourg
country: Switzerland
facility: Laboratory for Cognitive and Neurological Sciences
city: Fribourg
country: Switzerland
facility: Hôpital Cantonal de Fribourg
city: Geneva
country: Switzerland
facility: University Hospital Geneva
Study officials:
affiliation: University of Fribourg
name: Jean-Marie Annoni, Prof. Dr.
role: PRINCIPAL_INVESTIGATOR
References:
citation: Friederici AD, Gierhan SM. The language network. Curr Opin Neurobiol. 2013 Apr;23(2):250-4. doi: 10.1016/j.conb.2012.10.002. Epub 2012 Nov 9.
citation: Tortella G, Casati R, Aparicio LV, Mantovani A, Senco N, D'Urso G, Brunelin J, Guarienti F, Selingardi PM, Muszkat D, Junior Bde S, Valiengo L, Moffa AH, Simis M, Borrione L, Brunoni AR. Transcranial direct current stimulation in psychiatric disorders. World J Psychiatry. 2015 Mar 22;5(1):88-102. doi: 10.5498/wjp.v5.i1.88.
citation: Floel A. tDCS-enhanced motor and cognitive function in neurological diseases. Neuroimage. 2014 Jan 15;85 Pt 3:934-47. doi: 10.1016/j.neuroimage.2013.05.098. Epub 2013 May 30.
citation: Torres J, Drebing D, Hamilton R. TMS and tDCS in post-stroke aphasia: Integrating novel treatment approaches with mechanisms of plasticity. Restor Neurol Neurosci. 2013;31(4):501-15. doi: 10.3233/RNN-130314.
citation: Monti A, Ferrucci R, Fumagalli M, Mameli F, Cogiamanian F, Ardolino G, Priori A. Transcranial direct current stimulation (tDCS) and language. J Neurol Neurosurg Psychiatry. 2013 Aug;84(8):832-42. doi: 10.1136/jnnp-2012-302825. Epub 2012 Nov 8.