The Effect of Aging on Reversal and Extradimensional Shifts in Jordan

Abstract

A two-phase discrimination shift design was used in which 192 Jordanian subjects in the age groups 50-59, 60-69, and 70 years and older were shifted following criterion learning of a discrimination task to either a reversal (R) shift or an extradimensional (ED) shift. Like older children and young adults, subjects in the 50-59 age group executed an R shift faster than an ED shift. Subjects who were 70 years or older, however, found the ED shift easier than the R shift, just as is traditionally found with preschool children. The reversed ontogenetic trend was explained in terms of Kendler and Kendler's two-stage mediational theory.