A basic mechanism for synaptic plasticity, posited to underlie learning and memory, through which an increase in synaptic efficacy arises from the persistent stimulation of the postsynaptic cell by the presynaptic cell. Thus, when an axon of cell A is close enough to excite cell B and is repeatedly involved in firing it, some growth process or metabolic change ensues in one or both cells such that efficiency of A, as one of the cells firing B, is increased. However, if A fires and B does not, then the connection between them is weakened. In connectionist modelling, it has become a technique for selectively weighting the strength of connections between neurons.
See Activity-dependent organization, Connectionist models, Hebbian learning, Plasticity (neural), Synapse