Differential salivary conditioning to traces.

Abstract

To reconcile trace-conditioning data suggesting effective traces of over 1 min. with delayed-reward and recent memory data suggesting effective traces of about 5 sec, salivary conditioning in dogs to tone CSs was used. Trace discrimination at an 8-sec. interval was virtually as effective as 8-sec. delayed discrimination. Supplementary experiments suggested that this superiority over other methods is attributable, in part, to CS complexity in previous studies rather than the present use of classical conditioning. Trace discrimination with a 16-sec. interval was significant but weak. These results implied that simple long-trace conditioning does not reflect true conditioning to a trace, which requires at least discrimination and a fixed interval throughout training.