The role of gross locomotor restriction in the acquisition of motor and cardiac conditional discrimination in the dog

The effects of gross locomotor restriction and lack of restriction, respectively, on the acquisition of a motor and cardiac discrimination task was investigated. Litter-mate dogs were used in a counterbalanced design involving two treatment conditions (free and restrained) and two discrimination learning problems. Each learning problem included eight daily training sessions with 10 CS+ tones and ten CS—tones presented randomly. The US was a shock to the left foreleg. Degree of foot flexion and percentage change in heart rate in response to CS tones were recorded. Dogs subjected initially to the free condition manifested a superior and more rapid motor and cardiac discrimination than Ss initially restrained. The free condition was not as facilitatory when presented to Ss which first had been exposed to the restraint condition. The results are discussed in terms of activation and negative transfer.