PHARMACOLOGICAL STIMULI CONTROL - APPLICATIONS IN PSYCHOPHARMACOLOGY

Amain purpose of pharmacological research is to identify new drugs and to determine their mechanism and site of action; such findings beside s the therapeutical benefit will improve our knowledge of the physiopa thology of the diseases. Usually, through the comparison in different experimental models it is possible to determine the therapeutical and collateral effects of a drug. Since there are a large number of experi mental models it is not always convenient or efficient to search throu gh all those models. Drug discrimination procedures (or more appropria tely, stimulus control of drugs) may offer an efficient alternative to establish the similarities and differences between drugs. The use of these models has become extended, particularly within psychopharmacolo gy, so it is convenient to understand the theoretical principles beyon d the model to evaluate its deficiencies and worth. As to drug discrim ination procedures, when comparing some drugs, one of them is establis hed as discriminative stimulus; such drug, therefore, acquires the pro perty of controlling behavior through the stimulus cue that it produce s. Under the effect of this drug, the subject must learn to emit a par ticular behavior which is correlated with a particular reinforce. On d ifferent occasions, the same subject is trained to emit another respon se correlated with some other reinforce. After performance criteria, t he training drug is substituted on generalization tests with a novel o r test drug to determine the similarity between them in a particular s et of dimensions which were varied (effect of the drug, dose, mechanis m of action, etc.). It is assumed that response selection will be a di rect function of the similarity between the drugs. This particular mod el is exemplified with serotonin partial agonists for the 5-HT1A recep tor; this class of compounds were selected due to the great interest t hese compounds have promoted after their possible application on depre ssion, anxiety and food regulation, among other possible effects.