Visual Modulation of Acoustic Reflex Measurements: Insights Into Sensory Integration.

OBJECTIVE

The aim was to investigate the impact of visual tasks on acoustic reflex thresholds (ARTs) and AR latencies (ARLs) during AR measurements.

METHODS

A total of 31 participants (17 female, 14 male; mean age: 20.3 ± 1.8 years) with normal hearing and Type A tympanograms were included. ARTs and latencies were measured using a 226 Hz probe tone under five distinct conditions: (1) resting with no visual task, (2) eyes comfortably closed, (3) fixed gaze on a stationary object, (4) saccadic eye movements, and (5) optokinetic eye movements. Data were analyzed using repeated measures ANOVA with Bonferroni correction applied for post hoc comparisons.

RESULTS

ARTs were significantly lower in the condition of eyes closed compared to fixed gaze, at both 1 and 2 kHz (p < 0.05). ARLs at 500 Hz were significantly shorter in the condition of fixed gaze compared to saccadic eye movements (p < 0.05). A significant interaction between frequency and condition was observed for ARTs, indicating frequency-specific modulation by visual tasks, whereas no significant frequency and condition interaction was found for ARLs.

CONCLUSION

Visual tasks have a measurable effect on ARTs and latencies, likely due to cross-modal interactions between the auditory and visual systems. These results highlight the importance of standardizing visual and attentional conditions during clinical AR testing. Further research is warranted to elucidate the underlying neural mechanisms and their clinical implications.