Differences in the sequential integration of form as a function of age and interstimulus interval.

The sequential integration of visual stimuli was studied in 12 young (18-28 years) and 12 old (51-62 years) men and women. Stimuli were constructed as corresponding word halves and inter-stimulus intervals (ISI's) of varied duration (0-150 msec.) were introduced between the presentation of the two halves. Correct word identification was found to be an inverse function of ISI for both young and old subjects. The number of stimuli correctly identified was significantly lower for the older subjects at all levels of ISI. None of the interactions of age, sex, and ISI was significant. The data appear to question the "stimulus persistence" model as applied to age differences in the temporal organization of form.