The use of the Bilingual Aphasia Test for assessment and transcranial direct current stimulation to modulate language acquisition in minimally verbal children with autism

Abstract

Minimally verbal children with autism commonly demonstrate language dysfunction, including immature syntax acquisition. We hypothesised that transcranial direct current stimulation (tDCS) should facilitate language acquisition in a cohort (n = 10) of children with immature syntax. We modified the English version of the Bilingual Aphasia Test (BAT) to test only basic canonical subject-verb-object sentences. We tested syntactic accuracy after teaching then testing all vocabulary from the subsequent syntax test to ensure validity of syntactic scoring. We used scaffolding sentences for syntax training. All procedures were performed both before and after tDCS. Results demonstrated a large effect size of the difference between pre-/post-tDCS groups (p < 0.0005, d = 2.78), indicating syntax acquisition. Combining a modified BAT with tDCS constitutes effective modalities for assessment and treatment of immature syntax in children with autism. Future studies should explore the BAT for patients with an inability to use or understand language, in particular bilingual children with autism.

Applications of transcranial direct current stimulation in children and pediatrics

“…Neuroanatomical and functional studies point to an alteration of synaptic maturation and cortical connectivity during early neurodevelopment, leading to a thinner cortical gray matter and alterations of frontal lobe connections, which may explain the different clinical manifestations (Courchesne and Pierce, 2005). From a theoretical point of view, noninvasive brain stimulation could be a useful way to modulate possible cortical mechanisms of this disorder and its functional effects (Schneider and Hopp, 2011). In children aged between 5 and 8 years, specific improvements in the scores of the Autism Treatment Evaluation Checklist and Children's Global Assessment Scale, but not in the Childhood Autism Rating Scale, were described after five consecutive sessions of anodal tDCS applied over the left dorsolateral prefrontal cortex (1 mA for 20 min), with the cathode placed on the right contralateral shoulder, when compared to sham stimulation (Amatachaya et al, 2014).…”

“…In children aged between 5 and 8 years, specific improvements in the scores of the Autism Treatment Evaluation Checklist and Children's Global Assessment Scale, but not in the Childhood Autism Rating Scale, were described after five consecutive sessions of anodal tDCS applied over the left dorsolateral prefrontal cortex (1 mA for 20 min), with the cathode placed on the right contralateral shoulder, when compared to sham stimulation (Amatachaya et al, 2014). Prefrontal stimulation was conducted to modulate language and cognitive functions, in which the prefrontal cortex is involved (Schneider and Hopp, 2011). With the same stimulation protocol, but applied in two single sessions of anodal tDCS separated by 1 week, improvements in the social scale and health and behavioral problems scale of the Autism Treatment Evaluation Checklist (but not in the language scale nor the sensory and cognitive awareness scale) and peak alpha EEG power have been described in children with the same age range ( Amatachaya et al, 2015).…”

Transcranial Electrical Stimulation: Methodology and Applications

“…Boggio, Sultani, and colleagues (2008) Other Clinical Cases. Schneider and Hopp (2011) found improved language (syntax) acquisition in a group of children with autism after a single 30-min tDCS session, with anodal stimulation over the left DLPFC. Vercammen et al (2011) found increased variability in performance on a probabilistic association learning task, after 20 min of anodal stimulation of the left DLPFC, in a group of patients with schizophrenia and suggested that this may imply beneficial effects in a subgroup of these patients.…”

Transcranial direct current stimulation in psychiatric disorders

“…An open study evaluating autistic patients with minimal verbal language have applied anodal tDCS over the Broca's area to improve language acquisition and the results showed that mean vocabulary scores were significantly higher after the intervention Schneider et al [104] . One double-blind, sham-controlled trial with 12 youths (age range from 10 to 17 years) with schizophrenia evaluated the tolerability of tDCS.…”