Stimulus-onset-asynchrony as the main cue in temporal order judgment

Elderly individuals often complain of difficulties in understanding speech, especially when heard against a background noise or when there are multiple speakers. One of the hypothesized reasons for these complaints is the reported age-related decline in auditory temporal processing (Schneider & Pichora-Fuller, 2001; Schneider, Daneman, & Pichora- Fuller, 2002). The rationale underlying this hypothesis is that the appropriate use of speech cues relies on several types of auditory temporal resolution, which research has shown is age-related (Gordon-Salant, 2005; Pichora-Fuller & Souza, 2003; Schneider & Pichora-Fuller, 2001; Schneider et al., 2002). A large number of studies have compared young and elderly subjects on a variety of auditory temporal resolution tasks and reported poorer resolution by the elderly as compared to the younger individuals. Elderly adults perform poorer than younger adults in gap detection tasks and need longer silent intervals to identify the presence of a gap when the marker signal is 250 msec or shorter...