A new model of active avoidance conditioning adequate for pharmacological studies

A model of rapid learning (active avoidance conditioning), using rats, is described which induces retention depending on the number of trials to which the animals are submitted. For 3 trials (double stimulation) adequately spaced, the memory trace lasts for 48 hr, whilst 6 trails induce a trace for 10 days. One single application of the double stimulation does not give any apparent retention in normal rats for 24 hr. This experimental fact is used to study and screen the activity of substances on the learning process. Animals treated with piracetam, pemoline, methamphetamin, strychnine, pyritinol and meclofenoxate before this single trial, display evidence of retention 24 hr later. Other substances, with known clinical CNS activites, eg, tranquillizers, analgesics, etc... show no positive effect on the mnesic trace.