The brain’s ability to synchronise with the tone and intonation of speech affects language processing and could help remediate dyslexia, a recent study by the Basque Center on Cognition, Brain and Language (BCBL) says.
Earlier neuro-scientific studies found that the brain can naturally adjust its wave frequency to the oscillations or rhythm of a sound source. However, little was known until now about the effect of this synchronisation on areas of the brain directly linked to language processing.
BCBL researcher Nicola Molinaro says the latest study demonstrates that synchronisation with speech intensifies when the brain is listening to low frequency waves, such as those associated with accent, tone and intonation. It also shows synchronisation activates parts of the brain, such as the Broca area, related to language processing.
In previous studies, BCBL researchers found that dyslexic children show a weak synchronisation with low frequency sounds, and therefore poor activation of the brain’s language processing regions. Young people who do not optimally process low frequency waves also struggle with decoding phonemes and words, which is linked to reading difficulties and dyslexia.
Childhood therapy can be used to stimulate low frequency auditory components, Molinaro suggests, thus clarifying the component sounds of language. For example, brain synchronisation can be measured while a dyslexic child is listening to speech and rewards can be used to improve synchronisation with low-frequency sounds. ‘It can help those who are out of sync to pay more attention to the tones, accents and intonations of speech,’ Molinaro adds. ‘With repeated training sessions we can help children with language-delay recover the mechanisms of attention.’
The BCBL researchers conducted a total of two studies with 35 and 37 individuals respectively. Participants listened to different spoken sentences for approximately six minutes and magneto encephalography (MEG), a non-invasive technique, was used to record and analyse their neuronal activity.
Molinaro says further research into cerebral synchronisation is needed.
The objective is to analyse what happens in the brains of bilinguals, in those who are learning a new language or in patients with brain injuries.
Through further research he hopes to analyse what happens to a subject when, for example, several people talk at the same time or the subject can see the speaker’s face when they are speaking.