THE FACE AS A REFLECTION OF SPEECH TO STUDY PROSODY

• The BCBL research center, in collaboration with the Biogipuzkoa Health Research Institute, aims to find out the cognitive origin of the ability to interpret and distinguish the intonation of anger, joy, exclamations or questions.

• Experts will test healthy people and patients with brain damage with the task of listening to sentences and then choosing the face that best expresses the words perceived.

• Deficits in prosodic comprehension are common in people who have suffered brain injuries such as stroke.

 

The proverb says that the face is the mirror of the soul, but what if it is also the mirror of speech? Or do we not change our gesture when we express anger or when we announce positive and joyful news? In the same way, our voice also varies depending on whether we are exclaiming or questioning something.

 

The ability we have to interpret and distinguish the intonation of words in each of these communicative situations is known as prosody and plays a key role in human interactions. So much so that a deficit in this prosodic comprehension, which is frequent in people who have suffered, for example, cerebral accidents such as a stroke, has a significant impact on their quality of life.

 

The aim of a new study by the Basque Center on Cognition, Brain and Language (BCBL) in Donostia, in collaboration with the Donostia University Hospital and the Biogipuzkoa Health Research Institute (IIS Biogipuzkoa), is to find the origin of prosody and its failures and to understand how it works at brain level in healthy people and those with neurological damage.

 

“We will study the phases involved in the interpretation of intonation with the idea of observing what influence a deficit in this function can have on speech comprehension and which brain region has the greatest relationship with prosody,” explains Giada Antonicelli, BCBL researcher.

 

Not surprisingly, as the expert adds, it is traditionally believed that emotional prosody (happy, angry or sad) is processed in the right hemisphere of the brain, while linguistic prosody (question, plea or exclamation) is processed in the left hemisphere. “This hypothesis is not supported by current evidence, which indicates a more complex distribution of prosody-related functions,” he says.

 

Healthy and brain-damaged participants

BCBL researchers will analyze the interpretation of prosody in two groups of participants: on the one hand, patients with brain damage from the Neurology Service of the University Hospital of Donostia, which collaborates in the study; and, on the other hand, healthy people over 18 years of age.

 

In this second group, the center is currently looking for volunteers who are right-handed, who have at least a high school education, who do not take medication for depression or anxiety, who do not have any neurological problems and who have no musical training.

 

“The idea is to assess the effects that age and brain lesions can have on prosody processing,” emphasizes Giada Antonicelli.

 

To do so, the experts will measure the behavioral and neuronal response of the participants through behavioral tests and magnetoencephalography (MEG), a non-invasive technique that detects the magnetic field produced naturally by the electrical activity of the brain.

 

In these tests, both healthy and sick people will undergo a simple task that will test their memory and linguistic abilities: listening to sentences and then choosing among 3 alternatives the face that best expresses the intonation of the words just heard, whether they are angry, happy, questioning, pleading or neutral.

 

The major novelty of the research lies in studying prosody in people with brain lesions using not only MEG, but also a statistical analysis technique called cortical tracking that estimates the synchronization between auditory stimuli and activity in the cerebral cortex.

 

“Previous research has shown that the brain and its oscillations tend to synchronize with the rhythm of speech, i.e., that neurons, the brain cells, slightly modify their activity to tune to the flow of speech. This is the first study to measure the cortical tracking of prosody in people with brain damage and in different age groups to find out how this synchronization influences prosodic comprehension,” emphasizes Simona Mancini, leader of the BCBL research group “Neurolinguistics and Aphasia”.

 

The results of the BCBL project, funded by the Spanish Ministry of Science and Innovation, will increase knowledge about the origin of prosody deficits and could help to guide rehabilitation therapies for people who have suffered a stroke, for example, and make them more effective.

 

Those who wish to participate and are available to come to BCBL’s facilities in the Miramón Technology Park, Donostia (Gipuzkoa), can contact the center by e-mail at participa@bcbl.eu, indicating in the subject: “Protrack Study”.

 

Sobre Biogipuzkoa

El IIS Biogipuzkoa es el centro de I+D+i de referencia del sistema sanitario público en Gipuzkoa, liderando el desarrollo de actividades científicas e innovadoras mediante su estructura colaborativa multi-institucional e interdisciplinar de excelencia. El IIS Biogipuzkoa potencia de forma preferente la investigación traslacional afrontando proyectos de valor añadido cuyos resultados reviertan en los y las pacientes, así como en la población general.

 

Sobre BCBL

El Basque Center on Cognition, Brain and Language es un centro internacional de investigación interdisciplinar con sede en San Sebastián para el estudio de la cognición, el cerebro y el lenguaje. Está impulsado por el Gobierno vasco con el objetivo de fomentar la ciencia y la investigación en Euskadi. Además, cuenta entre sus socios con Ikerbasque, Innobasque, la Diputación de Gipuzkoa y la Universidad del País Vasco/Euskal Herriko Unibertsitatea (UPV/EHU).