Unified pre- and postsynaptic long-term plasticity enables reliable and flexible learning

Area of Science:

• Neuroscience
• Synaptic Plasticity
• Computational Neuroscience

Background:

• Long-term synaptic plasticity is crucial for learning and memory.
• Plasticity can be expressed at either the presynaptic or postsynaptic terminal, or both.
• The functional impact of combined pre- and postsynaptic plasticity remains largely unexplored.

Purpose of the Study:

• To investigate the functional consequences of spike-timing-dependent plasticity (STDP) with both pre- and postsynaptic expression.
• To compare the effects of dual STDP with postsynaptic STDP alone on receptive field properties.
• To explore the role of dual STDP in memory formation and recall.

Main Methods:

• Computational modeling of neural circuits.
• Simulations of STDP with distinct pre- and postsynaptic expression rules.
• Analysis of receptive field properties (variability, discriminability).
• Investigation of memory traces and relearning dynamics.

Main Results:

• STDP with both pre- and postsynaptic expression resulted in receptive fields with lower variability and enhanced discriminability compared to postsynaptic STDP alone.
• The simulated receptive field changes align with experimental findings in sensory perception.
• A hidden postsynaptic memory trace was identified, facilitating rapid relearning of previously acquired information.

Conclusions:

• Presynaptic plasticity plays a critical role in refining neural representations and improving sensory discrimination.
• Combined pre- and postsynaptic plasticity provides a cellular substrate for memory savings and efficient relearning.
• Understanding the distribution of synaptic strength changes is essential for comprehending experience-dependent neural adaptations.