Homosynaptic plasticity

Homosynaptic plasticity is one type of synaptic plasticity. Homosynaptic plasticity is input-specific, meaning changes in synapse strength occur only at post-synaptic targets specifically stimulated by a pre-synaptic target. Therefore, the spread of the signal from the pre-synaptic cell is localized. Donald Hebb theorized that strengthening of synaptic connections occurred because of coordinated activity between the pre-synaptic terminal and post-synaptic dendrite. According to Hebb, these two cells are strengthened because their signaling occurs together in space and/or time, also known as coincident activity. This postulate is often summarized as Cells that fire together, wire together, which means that the synapses that have neurons with coincident firing are strengthened, while the other synapses on these neurons remain unchanged. Hebb's postulate has provided a conceptual framework for how synaptic plasticity underlies long-term information storage.In order to stabilize LTP and make it last longer periods of time, new proteins supporting this change are synthesized in response to stimulation at a potentiating synapse. The challenge that arises is how to get specific, newly synthesized proteins to the correct input-specific synapses they are need at. Two solutions to this problem include synaptic tagging and local protein synthesis.