Crowley, M. A. & Donahoe, J. W. (2004).
Matching: Its acquisition and generalization.
Journal of the Experimental Analysis of Behavior, 82, 143-159.
Choice typically is studied by exposing organisms to concurrent
variable-interval schedules in which not only responses controlled
by stimuli on the key are acquired but also switching responses and
likely other operants as well. In the present research, discriminated
key-pecking responses in pigeons were first acquired using a multiple
schedule that minimized the reinforcement of switching operants.
Then, choice was assessed during concurrent-probe periods in which
pairs of discriminative stimuli were presented concurrently.
Upon initial exposure to concurrently presented stimuli, choice
approximated exclusive preference for the alternative associated
with the higher reinforcement frequency. Concurrent schedules
were then implemented that gave increasingly greater opportunities
for switching operants to be conditioned. As these operants were
acquired, the relation of relative response frequency to relative
reinforcement frequency converged toward a matching relation. An
account of matching with concurrent schedules is proposed in which
responding exclusively to the discriminative stimulus associated
with the higher reinforcement frequency declines as the concurrent
stimuli become more similar and other operants-notably switching-are
acquired and generalize to stimuli from both alternatives. The
concerted effect of these processes fosters an approximate matching
relation in commonly used concurrent procedures.
Key words: matching, concurrent schedule, changeover response,
discrimination, generalization, multiple schedule, key peck, pigeon