Synaptic Plasticity (1)

Professor Tom O'Dell discusses synaptic plasticity - the strengthening and weakening of synaptic connections between neurons.

So the neural code, or the patterns of synaptic activity on both the pre- and postsynaptic side of the synapse, are sort of the crucial determinants of synaptic plasticity. In general, in many, many excitatory synapses in the brain – probably most if not all excitatory synapses in the brain – when a presynaptic partner of the synapse, when that cell is active at about the same time the postsynaptic cell is, that fulfills the requirement for the induction of long-tern potentiation, or LTP. Cells that are firing together at that same time – that pattern of activity, these two happening conjointly – that is the trigger, the condition, for causing long term potentiation. When cells are firing out of sequence, or out of synch, that in turn can cause the opposite change in synaptic strength. It can trigger long term depression, or LTD.