# ht_synapse – Synapse with depression after Hill & Tononi (2005)¶

## Description¶

This synapse implements the depression model described in [1], p 1678.

Synaptic dynamics are given by

\[\begin{split}P'(t) = ( 1 - P ) / \tau_P \\
P(T+) = (1 - \delta_P) P(T-) \text{ for T : time of a spike } \\
P(t=0) = 1\end{split}\]

\(w(t) = w_{max} \cdot P(t)\) is the resulting synaptic weight

For implementation details see: HillTononi_model

Warning

This synaptic plasticity rule does not take precise spike timing into account. When calculating the weight update, the precise spike time part of the timestamp is ignored.

## Parameters¶

The following parameters can be set in the status dictionary:

tau_P |
ms |
Synaptic vesicle pool recovery time constant |

delta_P |
real |
Fractional change in vesicle pool on incoming spikes (unitless) |

P |
real |
Current size of the vesicle pool [unitless, 0 <= P <= 1] |

## References¶

## Transmits¶

SpikeEvent