Pupillary Response to Auditory Stimuli in Depressive State

Abstract

Background: Previous reports indicate that depressed individuals have worse memory for negative information than other types of information. They tend to ruminate upon negative information with high sensitivity. Depressive subjects also tend to display greater sustained pupil dilation in response to negative information. Methods: We evaluated pupil diameter with charge coupled device (CCD) infrared camera while scoring depressive scale in 41 healthy elderly subjects. Six kinds of sounds were used as auditory stimuli with characters of startle-eliciting. The measurements of pupil were made in a rested state and done twice with pre- and post-auditory and light stimulations. The indexes of pupil responses were dilations for auditory stimulations and contractions for light stimulations. Results: The pupil diameter stimulated by emotional sound “glasses broken on the floor” was solely positive correlated with depressive score. The pupil contractions for light stimuli were weakly negative correlated with depressive score. Conclusion: Some emotional sounds with negative information could cause pupil dilation in depressive participants. This sound “glasses broken on the floor” would be a biological marker assistant to depressive diagnosis. J Neurol Res. 2016;6(1):8-11 doi: http://dx.doi.org/10.14740/jnr364w