Effects of Contingent and Non-Contingent Signals During Delay Interval on Response Acquisition by Rats
Resumen
Research on delay of reinforcement effects under temporally defined schedules
of reinforcement suggests delay effects are diluted under short cycle durations.
This conclusion is tentative because attempts to replicate the seminal
study conducted by Weil (1984) differed from the original study in a number of
ways. The present study attempted a more direct replication of Weil`s study
and also to extended the original manipulation to encompass two different signaled
delay of reinforcement procedures. Thirty-six naive rats were exposed
to a repetitive time cycle of 32-s. The cycle was divided into two portions, td and t delta. A response during td produced food at the end of the cycle; responses
emitted during t delta had no programmed consequences. For some
experimental groups td was signaled by a response-produced signal; in other
groups a non-contingent signal occurred during td ; in still other experimental
groups td was unsignaled. The placement of td was varied to produce two
different response-reinforcer temporal relations; td duration was also varied
to assess the generality of the results. Response rates were considerably
lower when td was at the beginning of the cycle than when the opportunity
to respond was at its end. Non-contingent signals produced low rates of responding;
in contrast response produced signals were associated with high
response rates. In general the results show that delay of reinforcement has
detrimental effects on response acquisition even under short reinforcement
cycles. Both non-contingent and contingent signals have facilitative effects on
the response acquisition process, but the former favors low rates of responding
and the later favors high response rates.
of reinforcement suggests delay effects are diluted under short cycle durations.
This conclusion is tentative because attempts to replicate the seminal
study conducted by Weil (1984) differed from the original study in a number of
ways. The present study attempted a more direct replication of Weil`s study
and also to extended the original manipulation to encompass two different signaled
delay of reinforcement procedures. Thirty-six naive rats were exposed
to a repetitive time cycle of 32-s. The cycle was divided into two portions, td and t delta. A response during td produced food at the end of the cycle; responses
emitted during t delta had no programmed consequences. For some
experimental groups td was signaled by a response-produced signal; in other
groups a non-contingent signal occurred during td ; in still other experimental
groups td was unsignaled. The placement of td was varied to produce two
different response-reinforcer temporal relations; td duration was also varied
to assess the generality of the results. Response rates were considerably
lower when td was at the beginning of the cycle than when the opportunity
to respond was at its end. Non-contingent signals produced low rates of responding;
in contrast response produced signals were associated with high
response rates. In general the results show that delay of reinforcement has
detrimental effects on response acquisition even under short reinforcement
cycles. Both non-contingent and contingent signals have facilitative effects on
the response acquisition process, but the former favors low rates of responding
and the later favors high response rates.