Long Term Potentiation

Long-Term Potentiation (LTP) is a phenomenon in which the efficacy of a synapse is changed when a pre-synaptic neuron and a post-synaptic neuron are active at approximately the same time (Matrinez & Derrick, 1996). These changes can last for a long period of time, hence the phrase "long-term". Originally discovered in Aplysi, LTP has also been found to occur in the mammalian nervous system, specifically the hippocampus. This is an extremely important finding as it suggests that LTP could be the cellular basis of learning and memory, especially when combined with the fact that the hippocampus is believed to be one of the major brain regions responsible for processing memories. Initially viewed as an excitatory mechanism -- that is, responsible for making synapses more excitatory -- a similar inhibitory process, long-term depression (LTD) has also been discovered (Artola & Singer, 1993).

LTP is one of the first examples of a mechanisms for neural implementation of a cognitive function. In particular, LTP can be viewed as implementing the computations required for Hebbian learning (Gerstner & Kistler, 2002).

References:

1. Artola, A., & Singer, W. (1993). Long-term depression of excitatory synaptic transmission and its relationship to long-term potentiation. Trends In Neurosciences, 16(11), 480-487.
2. Gerstner, W., & Kistler, W. M. (2002). Mathematical formulations of Hebbian learning. Biological Cybernetics, 87(5-6), 404-415.
3. Martinez, J. L., & Derrick, B. E. (1996). Long-term potentiation and learning. Annual Review of Psychology, 47, 173-203

(Revised February 2010)