Summary: A new study reveals that blind people remember speech and language better than sighted people. Researchers say that blind people use language as a mental aid to remember information.
Source: Johns Hopkins University
Blind people can remember speech better than sighted people, but a person’s ability to see makes no difference in how they remember sound effects, a new study from Johns Hopkins University and the University of California, Irvine found.
“It’s interesting that people who are blind showed an advantage only with verbal memory,” said senior author Marina Bedny, an associate professor of psychology and brain science at Johns Hopkins, whose work regularly compares the brains of blind and sighted individuals.
“Blind people can use language as a mental aid to remember information.”
The findings appear in Experimental brain research†
Researchers performed two memory tests on 20 blind adults and 22 blindfolded sighted adults. They wondered whether blind participants would perform better than sighted people at remembering spoken sounds. First, the participants listened to series of letters, followed by a delay.
Then they heard the same sequence or a “foil” sequence in which a letter is replaced or placed in the wrong position. The participants then rated whether the second set of letters was the same as the first.
For the second test, they listened to letters while solving math equations with suggested answers. The participants determined whether the solutions of the equations were correct, followed by saying the letters back.
As the researchers expected, blind participants outperformed sighted participants in remembering speech. The results of another phase of testing, which required solving math equations and recalling letters, confirmed researchers’ predictions. Blind participants again remembered more letters than sighted participants, despite being forced to mentally multitask.
“Blind people use their memory a lot more every day to remember things, while sighted people can rely on visual cues to recall information,” said Karen Arcos, lead author and a blind postdoctoral researcher at the University of California, Santa Cruz. her PhD from the University of California, Irvine.
“We think the benefits of blind people on the verbal tests come from more practice in remembering information. The area of the brain responsible for vision in sighted people, the ‘visual’ cortex, is reused for other functions in blind people. Maybe it improves the language processing of the blind.”
In another experimental phase, participants listened to two streams of sound effects and were asked whether sounds matched. The researchers used sound effects such as tones and high-pitched beeps instead of everyday sounds to ensure that sounds could not be labeled with words. In this task, the blind and the sighted performed essentially the same.
“By using meaningless sound effects, we prevented participants from using language to remember them. This reduced the habitual memory advantage of blind people,” Bedny said.
Bedny is now studying what enables blind people to outperform sighted people at remembering words, letters and numbers. In addition, she plans to investigate whether the “visual” cortex contributes to better memory for speech and language in blind people.
About this news about visual neuroscience and memory research
Writer: press office
Source: Johns Hopkins University
Contact: Press Office – Johns Hopkins University
Image: The image is in the public domain
Original research: Closed access.
“Superior verbal but non-verbal memory in congenital blindness” by Karen Arcos et al. Experimental brain research
Superior verbal but non-verbal memory in congenital blindness
Previous studies suggest that people who are congenitally blind outperform sighted people on some memory tasks. Whether blindness-associated memory benefits are specific to verbal materials or also observed with nonverbal sounds has not been established.
Congenital blind persons (n= 20) and age and education were consistent with blindfolded sighted controls (n= 22) performed a series of auditory memory tasks.
These include: verbal forward and backward letter sequences, a complex letter sequence with intermediate comparisons, as well as two matching recognition tasks: one with verbal stimuli (ie letters) and one with nonverbal complex meaningless sounds. By replicating previously observed findings, blind participants outperformed sighted people on forward and backward letter span tasks.
Blind participants also remembered more letters on the complex letter span task, despite the interference of intermediate comparisons. Critically, the same blind participants showed greater benefits on the verbal compared to the nonverbal recognition task.
These results suggest that blindness selectively improves memory for verbal material. Possible explanations for blindness-related benefits of verbal memory include blindness-induced memory exercise and ‘visual’ cortex recruitment for verbal processing.