The purpose of this paper is to examine the relationship between the general processes of arousal and sensitization and the response increment processes at the cellular level, which have been considered as model systems of behavioural plasticity, i.e. the kindling effect and long-term potentiation in hippocampal pathways. From the published literature it appears that kindling and potentiation may be considered as model systems of sensitization and arousal. Moreover, research on these potentiation effects gives support to the hypothesis of specific arousal systems in the brain which mediate learning and memory. It is proposed that a multidisciplinary approach, including data from behavioural neurobiology and from psychophysiological studies, can contribute to better knowledge of the biological basis of learning.