MODEL SYNAPSES WITH FREQUENCY POTENTIATION CHARACTERISTICS CAN COOPERATIVELY
ENHANCE HEBBIAN LEARNING
C. Andrew Chapman and Suzanna Becker
Frequency potentiation, a short-term form of plasticity, is an enhancement in
the amplitude of neuronal responses to each pulse in a train of stimulation
pulses which occurs when the pulses are delivered within a certain frequency
range. In the model, theta-frequency input from the subiculum via synapses
with frequency potentiation characteristics cooperatively enhances Hebbian
learning in pyriform cortex efferents to the entorhinal cortex, particularly
when the inputs are phase-locked. This effect is further enhanced when
inhibitory interneurons are added within the entorhinal layer. These
simulations demonstrate a mechansism for frequency-dependent heterosynaptic
modulation of Hebbian learning, and may be relevant to theta rhythm-related
enhancements of plasticity in the hippocampal formation.
Back to Sue Becker's home page