[Neurobiology of memory]

A first part of the paper describes the neuro-anatomical structures involved in the processes of memory and their connections, as demonstrated by the recent hodological methods. The classical view of the Papez's limbic circuitry represents only one part of the reality. Several other circuits do exist, including those relaying in the amygdaloid complex and in the septal area. Actually, all these structures can be understood as the nodal points of a set of cortico-subcortical networks, where information is distributed and processed according to the cognitive demand and finally stored in the cortical layers. In a second part, the various mechanisms at the cellular level in relation with the processes of learning, are discussed (i.e. plasticity of synaptic transmission, dynamic neuronal changes at the morphological, electrophysiological and metabolic levels). The role played by humoral neuromodulation is examined, although it remains largely unknown at present (i.e. acetylcholine, catecholamines, GABA, glutamate, neuropeptides). Unfortunately, therapeutical implications from these fundamental data stay mostly frustrating up to now. Finally, relationships between sleep and memory are considered. The abundant experimental work performed on animals mainly stresses the REM-sleep. However, data from the human pathology are much less conclusive, and no clear evidence of a specific interaction between one aspect of sleep and one kind of memory emerges. To conclude, a few remarks are warranted on the intimal links existing between the anatomical-functional set of memory and the neurobiological bases of behavioural responses and anticipatory processes.