Cognitive Ability Influences Speech Perception in Noisy Environments
Imagine you’re at a busy café with a friend. It’s quite noisy, and focusing on the conversation feels tough. It might seem like you could use a hearing aid. However, a recent study indicates the challenges in understanding speech may be tied to cognitive ability instead.
Researchers investigated three groups: individuals with autism, those with fetal alcohol syndrome, and a typical control group. They discovered a strong link between cognitive ability and how well participants—each with normal hearing—processed speech in noisy settings.
“The connection between cognitive skills and speech perception was evident across all diagnostic categories. It was consistent in all three groups,” explained Bonnie Lau, the lead researcher and an assistant professor in otolaryngology–head and neck surgery at the University of Washington. She also oversees studies on auditory brain development.
The research is detailed in PLOS One.
Lau pointed out that, although the study involved fewer than 50 participants, which calls for further validation in broader groups, the results highlight that cognitive ability plays a significant role in listening performance in challenging acoustic environments, such as lively classrooms or social gatherings.
To explore their hypothesis, the researchers designed an experiment involving individuals with autism and fetal alcohol syndrome. Participants with these conditions often report listening difficulties in congested atmospheres, despite having normal hearing. Interestingly, those from these “neurodivergent” groups exhibited a broader spectrum of IQ scores—some notably higher—compared to the neurotypical participants.
The study consisted of 12 participants with autism, 10 with fetal alcohol syndrome, and 27 matched individuals in the control group, aged between 13 and 47 years.
Initially, all participants underwent an audiology screening to confirm their hearing was clinically normal. Then they donned headphones and engaged with a computer program designed to present a complex listening task.
Participants were exposed to a main speaker’s voice while two additional “background” voices emerged, all speaking at the same time. The primary speaker’s voice was male, while the background voices included both genders. Each voice spoke a single sentence that began with a call sign followed by a color and number, like “Ready, Eagle, go to green five now.”
Using the computer program, participants were tasked with selecting a colored, numbered box that matched the primary speaker’s statement as the volume of the other voices gradually increased.
They also took brief, standardized intelligence tests—both verbal and nonverbal—as well as perceptual reasoning assessments. These scores were compared to their performance in the multitalker listening challenge.
Researchers found a significant relationship between directly assessed intelligence and multitalker speech perception, highlighting that cognitive ability was correlated with speech perception thresholds in all three participant groups.
Lau noted that effective listening in complex environments involves significant brain processing. “You need to separate streams of speech, focus on the speaker of interest while filtering out competing noise, and comprehend linguistically—all of this adds to the cognitive load when trying to communicate in noisy settings.”
The study challenges a common misconception that those who struggle to hear must have peripheral hearing loss. “You can have difficulty listening in environments like restaurants without having hearing loss,” she mentioned.
The authors suggest that neurodivergent individuals or those with lower cognitive abilities might benefit from an assessment of their listening environments, potentially leading to useful classroom adaptations, such as seating adjustments or the use of hearing-assistive technology.
Lau and her colleagues are affiliated with the University of Washington’s Virginia Merrill Bloedel Hearing Research Center. Other co-authors hail from various departments across the University of Washington and the University of Michigan.
