title: ERP correlates of auditory goal-directed behavior of younger and older adults in a dynamic speech perception task.
abstract: The ability to understand speech under adverse listening conditions deteriorates with age. In addition to genuine hearing deficits, age-related declines in attentional and inhibitory control are assumed to contribute to these difficulties. Here, the impact of task-irrelevant distractors on speech perception was studied in 28 younger and 24 older participants in a simulated "cocktail party" scenario. In a two-alternative forced-choice word discrimination task, the participants responded to a rapid succession of short speech stimuli ("on" and "off") that was presented at a frequent standard location or at a rare deviant location in silence or with a concurrent distractor speaker. Behavioral responses and event-related potentials (mismatch negativity MMN, P3a, and reorienting negativity RON) were analyzed to study the interplay of distraction, orientation, and refocusing in the presence of changes in target location. While shifts in target location decreased performance of both age groups, this effect was more pronounced in the older group. Especially in the distractor condition, the electrophysiological measures indicated a delayed attention capture and a delayed re-focussing of attention toward the task-relevant stimulus feature in the older group, relative to the young group. In sum, the results suggest that a delay in the attention switching mechanism contribute to the age-related difficulties in speech perception in dynamic listening situations with multiple speakers.
authors.affiliation: Leibniz Research Centre for Working Environment and Human Factors at the Technical University of Dortmund (IfADo), Ardeystraße 67, D-44139 Dortmund, Germany. Electronic address: getzmann@ifado.de.
authors.forename: Stephan
authors.initials: S
authors.lastname: Getzmann
authors.affiliation: Leibniz Research Centre for Working Environment and Human Factors at the Technical University of Dortmund (IfADo), Ardeystraße 67, D-44139 Dortmund, Germany.
authors.forename: Michael
authors.initials: M
authors.lastname: Falkenstein
authors.affiliation: Leibniz Research Centre for Working Environment and Human Factors at the Technical University of Dortmund (IfADo), Ardeystraße 67, D-44139 Dortmund, Germany.
authors.forename: Edmund
authors.initials: E
authors.lastname: Wascher
mesh_terms: D000161:Acoustic Stimulation; D000328:Adult; D000368:Aged; D000375:Aging; D000704:Analysis of Variance; D004215:Distance Perception / Q000502:physiology; D004569:Electroencephalography; D005072:Evoked Potentials, Auditory / Q000502:physiology*; D005260:Female; D007839:Functional Laterality; D006040:Goals; D006801:Humans; D008297:Male; D008875:Middle Aged; D011930:Reaction Time / Q000502:physiology; D013067:Speech Perception / Q000502:physiology*; D055815:Young Adult
keywords: Aging; Mismatch negativity (MMN); P3a; Reorienting negativity (RON); Speech perception; “Cocktail Party” scenario