Jhr. Maes et Jmh. Vossen, Acquisition of discriminations involving ambiguous or non-ambiguous features: an evaluation of two configural learning models, BEHAV PROC, 53(3), 2001, pp. 191-201
The present rat experiment evaluated the validity of two formal accounts of
configural learning in the framework of discrimination tasks involving the
serial presentation of feature and target stimuli: Rescorla's (1973) modif
ication of the Rescorla-Wagner model (1972) and the Pearce model (1987). Th
e first, ambiguous: feature task was of the form X -->A+, Y -->A-, X -->B-,
Y -->B+, in which X and Y represent visual features, '-->' signifies a ser
ial arrangement, A and B are auditory target stimuli, and '+' and '-' symbo
lise food-reinforcement and non-reinforcement, respectively. The second, no
n-ambiguous feature task was of the form: X -->A+, Y -->A-, X -->B, Y -->B-
. The former task was much more difficult to solve than was the latter task
. The Rescorla model is able to account for the observed differences betwee
n the two tasks in learning rates and in the associative strength of featur
e X with more plausible parameter values than is the Pearce model. It is su
ggested that models acknowledging a role for both elemental and configural
learning can better account for discrimination learning in discrimination t
asks of the sort presented in this study than do models that exclusively al
low for configural learning. (C) 2001 Elsevier Science B.V. All rights rese
rved.