2023-07-05 17:30:00
The brain has not finished revealing its mysteries. Recently, scientists made a new discovery that challenges a long-held belief. In Neurobiology of Language, they explain that they found that our auditory lexicon, the memory of the words we hear, is located at the front of the primary auditory cortex. However, previous research had shown that it was in the back. For the authors, this could have “an impact on recovery and rehabilitation following a brain injury such as a stroke”.
Understanding Word Storage in the Brain Using MRIs
“Since the early 1900s, scientists believed that spoken word recognition took place behind the primary auditory cortex, but this model did not fit well with many observations of patients with speech recognition deficits, such as victims of ‘a stroke,’ says Maximilian Riesenhuber, professor of neuroscience at Georgetown University Medical Center in Washington and lead author of the study. To identify the exact location of this brain area, the researcher and his team recruited 26 people: all underwent three series of MRIs to examine how their brains processed speech. These various examinations enabled them to discover this zone at the front of the primary auditory cortex.
Stroke: hope in the management of aphasia?
“Our discovery of an auditory lexicon more forward in the brain provides a new target area to help us understand speech comprehension deficits.” He explains that it could be interesting to carry out trials with people who have suffered strokes or brain damage, to understand the effects of an intervention in this area of the brain.
On average, 40% of stroke victims have significant sequelae, according to Inserm. Aphasia is one of the most common: it is a disorder of oral and written language, which affects speech and comprehension. “In about a third of patients, severe aphasia limiting communication persists, specifies Inserm. Another third recovers enough to communicate correctly, despite sequelae.” To recover, patients undergo speech therapy sessions, but this rehabilitation is “long and intensive” according to theHealth Insurance.
Brain area linked to words heard: what could this discovery be used for?
This discovery could have other implications: according to the authors, it could also be used to better understand the links between the storage of written words and spoken words in the brain. “We know that when we learn to speak, we rely on our auditory system to know if the sound we have produced faithfully represents our intention, adds Josef Rauschecker, co-author of the study. We use this to refine our future attempts to pronounce this word. However, the brain process for this remains poorly understood.” A better understanding of this could help to decipher the processes at play when children acquire speech or when adults learn a long second.
1688594771
#part #brain #stores #vocabulary #thought