1. Spike timing dependent plasticity
Domina Petric, MD 1

2. STDP
Spike timing dependent plasticity is a framework for understanding plasticity in the brain: one postsynaptic spike at a time.

3. STDP
When the presynaptic activity happens before the postsynaptic activity, there is long term potentiation (interval between presynaptic and postsynaptic activity has to be less than 20 ms).
If the presynaptic activity happens after the postsynaptic activity, there is long term depression.

4. Hebb´s postulate
Coordinated activity of a presynaptic terminal and a postsynaptic cell would strengthen the synaptic connection between them.
Uncoordinated activity between the synaptic partners would weaken their synaptic connections.

5. Hebb´s postulate and STDP
STDP explains how synaptic change can occur one postsynaptic spike at a time under physiological conditions that are found in real neural networks.

6. Hebb´s postulate and STDP
Presynaptic activity that occurs before the postsynaptic activity is coordinated activity of a presynaptic terminal and a postsynaptic cell that will cause long term potentiation.

7. Hebb´s postulate and STDP
Presynaptic activity
Postsynaptic activity
Before
After
Coordinated activity: long term potentiation
20 ms interval

8. Hebb´s postulate and STDP
Postsynaptic activity that occurs before the presynaptic activity is uncoordinated activity of presynaptic terminal and a postsynaptic cell that will cause long term depression.

9. Hebb´s postulate and STDP
Presynaptic activity
Postsynaptic activity
After
Before
Uncoordinated activity: long term depression
20 ms interval

10. Conclusion
Change at the synaptic level can produce changes in wiring patterns of neuronal circuits.
Synaptic changes accumulate throughout a network of interconnected neurons.

11. Literature
Leonard E. White, PhD, Duke University