Matching-to-sample performance in older and younger adults.

The present experiment studied the influence of simultaneous matching-to-sample (SMTS) or delayed matching-to-sample (DMTS 0 s) using the many-to-one (MTO) or one-to-many (OTM) training structures on the formation of equivalence classes in older and younger adults. Sixty older adults and 16 younger adults were divided into four groups: (1) SMTS-MTO, (2) SMTS-OTM, (3) DMTS 0 s-MTO, and (4) DMTS 0 s-OTM. All of the younger adults established conditional discriminations, whereas only 35 of the 60 older adults did the same. The SMTS-OTM had the lowest number of trials to mastery criterion for the older adults, and the SMTS-MTO group had the highest number of participants forming equivalence classes. In the younger adults, the differences in trials to mastery criterion were minimal, and there were no differences in the equivalence tests across groups. The older adults had a higher reaction time to comparison stimuli than the younger adults. [ABSTRACT FROM AUTHOR]