Why Closing Your Eyes in Noise Makes Hearing Fainter Sounds Harder

New research reveals how vision affects our ability to hear in noisy environments. Scientists found that closing your eyes can actually make it harder to pick out faint sounds. Meanwhile, watching a matching video improves hearing sensitivity by helping the brain predict when a sound will occur.

The study tested volunteers under four different conditions: eyes closed, eyes open with a blank screen, static visual stimulation, and dynamic visual stimulation. Results showed that shutting the eyes raised the detection threshold by an average of 1.32 decibels. In contrast, dynamic visuals that matched the sound lowered the threshold by 2.98 dB, while static visuals reduced it by 1.60 dB.

EEG recordings provided further insight. When participants closed their eyes, the brain’s 'avalanche critical index' dropped by 22.3% to 45.2% across five auditory stimuli compared to a blank screen. This suggests the brain enters a state of 'neural criticality', aggressively filtering sounds and making faint noises harder to detect. The findings support the idea that the brain performs best when visual and audio cues are synchronised. Watching a dynamic video that aligns with the sound significantly boosts hearing sensitivity. The researchers propose a new framework, based on brain dynamics theory, to explain how vision influences auditory perception in complex, noisy settings. Looking ahead, the team plans to explore this relationship further. Future experiments will include testing how incongruent pairings of visual and auditory stimuli affect perception.

The study highlights the strong link between sight and sound in how we process noise. Closing the eyes in loud environments weakens the brain’s ability to detect faint sounds, while matching visuals enhance hearing. These results could inform new approaches to improving auditory focus in challenging acoustic spaces.