The mismatch negativity (MMN) was used as a probe
to evaluate changes, with age, of transient auditory memory.
Subjects were 16 young (M = 23 years) and 16 old
(M = 72 years) people. Standard auditory stimuli
were presented in trains of eight tones (1000 Hz) with
either a 1-s or 8-s intertrain interval (ITI). Occasionally,
the first stimulus of a train was replaced with a 1200
Hz tone (deviant). The MMN was recorded while subjects
watched a silent movie and ignored the sounds. Both groups
of subjects showed an MMN response to deviant stimuli under
the 1-s ITI condition, but MMNs were only seen for some
subjects under the 8-s ITI condition. After MMN recording,
subjects performed a discrimination task to the tones used
for recording MMNs. Accuracy for both groups was near 100%
at both ITIs. These results suggest that generation of MMN
is a function of the perceptual grouping of the acoustical
stimuli and that the integrity of perceptual grouping may
be maintained with increased age.