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The integrative activity of the brain is particularly related to the telencephalic level of CNS. Drugs affecting learning and memory usually interfere with the reticular or limbic system, and are either stimulants or sedatives. In contrast, Piracetam (U C B 6215) is an atoxic compound which, up to dosages such as g/kg, does not interfere with autonomic functions, general behavior, level of wakefulness, the limbic system, etc. Yet, in dosages such as mg/kg it improves several learning and memory abilities, protects against experimental amnesic agents, facilitates EEG recovery after severe hypoxia and also facilitates interhemispheric transfer (transcallosal evoked potential and learned behavior). Discussion is made on the basis of the particular neuropharmacology as well as on the available biochemical and human clinical correlations to emphasize the selectivity of this compound on telencephalic integrative mechanisms. Piracetam is presented as the first-comer of a new psychotropic class for which the termnootropic is proposed.

Rats were trained on a continuously reinforced bar-press response for water reward. Seven days later they were retested for retention, with or without pretest injection of the nootropic drug, piracetam. Drug-treated animals had significantly shorter response latencies than saline-treated animals. The results are interpreted as a facilitation of retrieval processes after forgetting. The experiment was extended under extinction conditions and it was found that after three sessions there was a tendency to facilitate extinction when response latency is used as the extinction index. The clinical interest of a drug which facilitates the retrieval aspect of the memory process without impairing extinction is discussed.

Nootropics were proposed as a class of psychoactive drugs selectively improving efficiency of higher telencephalic, integrative activities (Giurgea, 1972). The main features of the nootropic pharmacology are: (1) enhancement of learning acquisition (water-maze, Y-maze, “drinking”-test, spinal fixation active avoidance) and resistance to impairing agents (hypoxia, ECS, chemicals, sensory deprivation, age); (2) facilitation of interhemispheric transfer of informations (callosal evoked potentials, visual discriminative learning); (3) enhanced resistance to brain “aggressions” such as nitrogen hypoxia, experimental high-altitude or drugs overdosing; (4) increased tonic, cortico - subcoitical “control” (LGB-induced nystagmus inhibited and spinal fixation facilitated by Piracetam); (5) absence of usual pharmacological effects such as sedation, stimulation, autonomic modulations or toxicity, even in very high dosages. All experimental features are thoroughly correlated with human pharmacoclinical and therapeutic data supporting the view that nootropic activity is based on a functional telencephalic selectivity. Geropsychiatric implications are discussed relative to (1) geropsychiatric self-perpetuating “vicious” circle (Lehmann, 1975); (2) cerebral hypoxia; (3) reduced, “dys-adaptive” plasticity with aging; (4) CNS-inhibitory reduced efficiency and sensory deprivation induced deficits.

In an operant conditioning situation a visual stimulus, presented about 40 times per trial, was used in a control group of Wistar rats, to learn to avoid an electric shock.

Les experiences discutees ont porte sur le rOle de la motivation — sous la forme d'un renforcement —dans l'etablissement de reponses conditionnees instrumentales chez le rat. Les resultats obtenus sur un groupe experimental et un groupe de contrOle comprenant chacun 7 animaux, montrent que la contiguite temporelle de 2 stimuli neutres (son-lumiere) permet aux animaux d'etablir entre ceux-ci une relation fonctionnelle sans intervention d'un facteur specifique de motivation.