Scientists find out why singing helps to restore speech after a stroke
Past studies have shown that singing helps to restore speech in stroke patients. In a new paper on this topic, scientists have unravelled the reasons for the therapeutic effects of singing on people with post-stroke aphasia, i.e. the complete or partial loss of the ability to speak and/or perceive the speech of others.
Approximately 40 per cent of stroke survivors experience such impairments, and in half of these cases they persist even a year after the stroke. Earlier, experts from the University of Helsinki (Finland) found that music and singing are effective in the rehabilitation of such patients. In particular, group therapy with singing showed good results: it helped to improve speech and increase social activity of post-stroke patients with aphasia.
However, the neural mechanisms by which this effect is achieved remained incompletely understood. This question was clarified by a fresh study by Finnish physicians from the same university. The results were published in the scientific journal eNeuro.
Scientists followed the effect of song therapy on people with post-stroke aphasia. Twenty-eight patients were randomly divided into a control group and an intervention group. All of them received standard treatment and rehabilitation, but participants in the second group additionally attended group singing classes once a week, as well as trained independently at home three times a week using a tablet and specialised software. The course lasted four months.
The patients were assessed by neuropsychological evaluation and MRI scans at the beginning of the experiment and after five months. In addition, participants reported their demographic data, completed music and clinical questionnaires, and informed the researchers about other types of rehabilitation they received.
MRI examinations revealed that singing helped restore the brain's language network. It covers different areas of the cerebral cortex involved in processing language and speech information, as well as conducting pathways with white matter, through which signals are transmitted from one point of the cortex to another. In patients with aphasia, this network is damaged.
The results of magnetic resonance imaging showed that in people who underwent song therapy, the volume of grey matter in the areas of the left frontal lobe responsible for speech and language increased. In addition, the connectivity of conductive pathways in the language network of the left and right hemispheres improved.
According to the researchers, their results demonstrated for the first time that rehabilitation of aphasic patients with singing is based on neuroplasticity, i.e. the brain's ability to recover and adapt. The positive changes recorded using MRI were accompanied by improved speech in the patients.
The new work has expanded knowledge of the benefits of song and music therapy in the rehabilitation of patients after stroke. According to the WHO, this pathology is among the top ten leading neurological causes of health loss. In Russia, more than 450 thousand people suffer a stroke every year.
Finnish doctors believe that singing therapy can be considered as a cost-effective addition to traditional forms of rehabilitation after stroke. In addition, this method is suitable for correction of mild speech disorders when other forms of rehabilitation are limited.