Language, Attention Gains Seen in Brain Stimulation Plus Cognitive Therapy

Combining conventional cognitive training with transcranial direct current stimulation (tDCS) — a non-invasive, painless brain stimulation approach — safely improves attention and language skills in girls and young women with Rett syndrome, a study reports.

Data suggest that tDSC potentiates the benefits of traditional training and support their combined use in Rett patients, but larger studies are needed, the researchers said.

Their study, “Effects of Combined Transcranial Direct Current Stimulation with Cognitive Training in Girls with Rett Syndrome,” was published in the journal Brain Sciences.

Increasing evidence suggests that combining traditional rehabilitative techniques with non-invasive brain stimulation, such as tDCS, benefits people with neurological, motor, cognitive, and language disorders.

tDCS uses constant, low-intensity electrical currents to stimulate specific parts of the brain via a pair of electrodes placed on the scalp. The approach can be used to bring nerve cells closer to, or farther from, firing, to strengthen or weaken neuronal communication and learning. As such, tDCS is thought to amplify the learning effects of traditional training.

However, tDCS’s use in combination with traditional rehabilitative training in Rett patients is largely unexplored.

Researchers in Italy evaluated whether combining cognitive training with tDCS improved attention and language skills in Rett syndrome.

They recruited 35 diagnosed young girls and women, with a mean age of 18.8 (range 13–35), from the Italian Rett Association. Four were soon excluded due to mutations in genes other than MECP2 (the main cause of Rett syndrome).

The remaining 31 patients were randomly assigned to 10 daily, 20-minute sessions of cognitive training in combination with either tDCS (18 patients) or a placebo stimulation (13 patients).

A treatment plan was based on participants’ level of behavior, cognition, and functional skills, and on cognitive–behavioral strategies. Its goal was to promote the production of vowels, speech sounds, and words.

Participants’ attention, language skills — number of vowels, speech sounds, and words — and brain electric activity (through an electroencephalogram) were assessed before and after the treatment period, as well as one month after the intervention.

Results showed that the combined intervention significantly improved attention and language skills — a higher number of vowels and speech sounds — compared with cognitive training alone. These benefits were also generally maintained after one month.

A similar trend was also observed for the number of words, but the difference between the two groups was not statistically significant.

The improvement in language skills was consistent with data from a previous study in Rett patients, “confirming the idea that speech training when combined with tDCS is more effective,” the researchers wrote.

People treated with the combined approach also showed significant improvements in electric activity parameters in the brain compared with those given cognitive training alone. No safety concerns were reported.

Combining tDCS with cognitive training for 10 days is a safe and effective approach to improve attention and language abilities in Rett patients, the team said.

“This study supports the use of tDCS as a promising and alternative approach in the [Rett syndrome] rehabilitation field,” the scientists wrote.

They added, however, that larger studies are needed to confirm these findings, to evaluate the potential effects of combined intervention on other cognitive abilities, and to identify the optimal parameters for a combined treatment protocol — including language, cognitive, and motor training plus tDCS.