Subproblem analysis of discrimination-shift learning

A new analysis of discrimination-shift learning is presented which is applicable to reversal (RS) vs extradimensional (EDS) shift comparisons in which stimulus pairing is unaltered throughout training. The analysis focuses on trial-by-trial performance on the individual pairs appearing in RS and in EDS. Applications of the analysis are presented which reveal that young children are likely to learn the pairs as independent subproblems, while older Ss treat the pairs as instances of a single problem. The former solution mode is found to be correlated with fast EDS and the latter mode with fast RS.