title: Comparison of Psychophysiological and Dual-Task Measures of Listening Effort.
abstract: OBJECTIVE
  We wished to make a comparison of psychophysiological measures of listening effort with subjective and dual-task measures of listening effort for a diotic-dichotic-digits and a sentences-in-noise task.
  
  
  METHODS
  Three groups of young adults (18-38 years old) with normal hearing participated in three experiments: two psychophysiological studies for two different listening tasks and a dual-task measure for a sentences-in-noise task. Psychophysiological variables included skin conductance, heart-rate variability, and heart rate; the dual-task measure was a letter-identification task. Heart-rate variability was quantified with the difference from baseline for the normalized standard deviation of R to R.
  
  
  RESULTS
  Heart-rate variability differences from baseline were greater for increased task complexity and for poorer signal-to-noise ratios (SNRs). The dual-task measure of listening effort also increased for sentences presented at a +5 dB SNR compared with a +15 dB SNR. Skin conductance was elevated for greater task complexity only, and similar across noise conditions. None of these measures were significantly correlated with subjective measures of listening effort.
  
  
  CONCLUSIONS
  Heart-rate variability appears to be a robust psychophysiological indicator of listening effort, sensitive to both task complexity and SNR. This sensitivity to SNR was similar to a dual-task measure of listening effort.
authors.forename: Scott
authors.initials: S
authors.lastname: Seeman
authors.forename: Rebecca
authors.initials: R
authors.lastname: Sims
mesh_terms: D000161:Acoustic Stimulation; D000293:Adolescent; D000328:Adult; D000704:Analysis of Variance; D001307:Auditory Perception / Q000502:physiology*; D005260:Female; D005712:Galvanic Skin Response / Q000502:physiology; D006339:Heart Rate / Q000502:physiology; D006801:Humans; D007807:Language Tests; D008297:Male; D005082:Physical Exertion / Q000502:physiology*; D011601:Psychophysics / Q000379:methods*; D011930:Reaction Time; D014796:Visual Perception / Q000502:physiology; D055815:Young Adult