Interaural level difference cues count when signals come from unexpected
Auditory spatial attention was investigated in younger and older adults
with good audiograms. In conditions of real spatial separation, the target
sentence was presented from one spatial location and competing sentences
were presented from two different locations. In conditions of simulated
spatial separation, differences in the apparent spatial locations of the
target and competitors were induced using the precedence effect. The identity
of the target voice was cued by a callsign presented either prior to or
following the target sentence, and four different probability specifications
indicated the likelihood of the target being presented at the three locations.
Overall, younger adults performed better than older adults. For both age
groups, performance improved with target location certainty, with a priori
target cueing, and when location differences were real rather than simulated.
This presentation will focus on the key finding that interaural level
difference cues conferred a significant advantage when the target occurred
at unlikely spatial listening locations, but not at likely
locations. Both auditory and attentional processes contributed to the
pattern of results in a similar fashion for both age groups.