Posted on 10 December 2013
They are testing whether a technique called Transcranial Direct Current Stimulation (tDCS) can be used to help recovery of comprehension, even for those who had a stroke several years ago. The research is funded by the Stroke Association.
Although the idea of electrical stimulation has been around for over a hundred years and is very safe, scientists and doctors have only recently started to use it as a way to improve stroke impairments. It is now employed to help people who are re-learning skills that they have lost after stroke.
The technique involves placing two pads on the head and passing a very small electrical current through these pads for around 20 minutes. This stimulates the brain cells underneath and causes them to increase their activity, leading to better performance on a wide range of tasks. Effects can last beyond the session itself, and have previously been shown to last at least several months after finishing the study.
Professor Beth Jefferies, who is leading the York research, said: “Our research is exploring comprehension after stroke and ways to improve this. It is thought that knowledge about the meanings of things is often maintained in the brain after stroke, but that the sorting mechanism is lost. It’s a bit like a library without a catalogue. Only the brightest book covers - the strongly remembered items - can be picked out properly.
“We are excited by the possibilities of tDCS, particularly for those people who haven’t fully regained their abilities and no longer receive speech and language therapy or physiotherapy.”
She warns, however, that the effects may not be seen in everyone, and they can be very subtle because the current is so small. In previous studies, not everybody benefited from tDCS, and it is often those who find the task most difficult that benefit the most.
Professor Jefferies said: “The technique is not painful, and it is fairly cheap and portable, so if the research finds that the method improves comprehension, it could be used to improve the outcomes of speech and language therapy.
“While there is no pain with this method, people can feel an itchy or hot feeling on the scalp.”
The researchers are seeking volunteers from Yorkshire and the surrounding area who have had a stroke at least six months ago and who might be willing to take part in the study. The researchers want to compare stroke patients with healthy volunteers aged from 45 – 85, for studies on language and memory problems that do not involve electrical stimulation.
To find out more contact Professor Beth Jefferies and her team on 01904 322928 or 01904 322937, write to her at the Department of Psychology, University of York, York, YO10 5DD, or e-mail: firstname.lastname@example.org.