- The research center is looking for participants with complete blindness or high visual impairment to perform different tasks at its facilities in Donostia.
- They will also analyze people without vision problems to identify if there are cognitive mechanisms that support better language skills in blind people.
- The experts will use a pioneering combination of neuroimaging techniques and methods such as the first atlas of the human thalamus, developed by the BCBL.
- The project is funded by the Provincial Council of Gipuzkoa, the Basque Government, the Ministry of Science and Innovation and the prestigious Marie Slodowska Curie grant, awarded by the European Commission.
Blind people show, according to different studies, superior abilities during speech processing, memory or attention. For example, it has been found that some are able to understand speech at very high speeds. While the majority of the population understands words at an average of 8 syllables per second, some visually impaired people are able to understand words at 22 syllables per second.
However, the cognitive mechanisms underlying these abilities are still unclear. This is largely due to the lack of research and knowledge about some of the brain areas that may be key in these processes, such as the thalamus. This brain structure sends sensory information gathered in the body to the cerebral cortex and, in addition, also appears to have a regulatory role in sensory information.
In this context, the neuroscientific research center Basque Center on Cognition, Brain and Language (BCBL) has started a new study for which it is looking for participants with different visual abilities (sighted, visually impaired and blind) with the challenge of observing at the brain level how they process memory, attention and speech.
BCBL experts will use a pioneering combination of neuroimaging techniques and tools, including the first atlas of the thalamus in humans, developed by the Basque center itself, magnetic resonance imaging equipment and optical coherence tomography (OCT), which is used to obtain information about the retina.
“With the help of the probabilistic atlas of the thalamus we will be able to determine with greater precision and reliability whether, in addition to the cerebral cortex, the usual focus of previous research in this field, subcortical areas such as the thalamus and its connections with the cortex also contribute to these skills in people with visual difficulties,” explains Ane Gurtubay, BCBL researcher.
According to the expert, there is scientific evidence suggesting that auditory processing at the level of the thalamus is different in the visually impaired population, and this new project seeks to find out whether these variations are related to an improvement in language processing, memory or attention.
Visual acuity less than 0.3
To carry out the study, the BCBL will have sighted, visually impaired and blind participants. In the latter groups, we are looking for volunteers with a visual acuity of less than 0.3 or a visual field of less than 20 degrees, and who have been so for at least the last 10 years.
The participants will be evaluated at BCBL’s facilities, firstly, by means of an optical coherence tomography to obtain information about their retina and, subsequently, they will perform different tests in an MRI to measure, while executing the tasks, the functioning of the posterior visual system, that is, of the part of the brain that processes vision.
“We will study people’s ability to process language, attend and memorize. In the attention task, for example, they will listen to a series of tones and will have to identify those that are similar or different; and in the memory task they will have to remember the order that a word occupied in a sequence that they heard previously,” adds Gurtubay.
The results obtained in the speech processing, memory and attention tests performed in the MRI will then be cross-checked with the thalamus atlas to study and identify the thalamic nuclei reliably in each individual and check whether their activity and structure are associated with language and memorization abilities.
“Understanding how information processing varies depending on visual abilities will help us to better understand the brain processes and mechanisms that can facilitate such processing, and this knowledge can be applied to improve the evaluation of people with deficits in these areas (aphasia, dementia or attentional deficits) and existing therapies,” says Kepa Paz-Alonso, leader of the “Language and memory control in BCBL” research group.
In addition, understanding the limits of brain reorganization in people with a different visual experience may facilitate finding more efficient methods of communication with the brain in cases where vision restoration is sought.
The new BCBL project is funded by the Marie Slodowska Curie postdoctoral fellowship awarded by the European Commission and is also supported by the Provincial Council of Gipuzkoa, the Basque Government and the Ministry of Science and Innovation.