Spike-timing-dependent plasticity in the human dorso-lateral prefrontal cortex

Area of Science:

• Neuroscience
• Cognitive Science
• Neurophysiology

Background:

• Spike-timing-dependent plasticity (STDP) modifies synaptic strength based on precise neural firing timing.
• The existence and function of STDP in large-scale human cortical networks remain debated.

Purpose of the Study:

• To investigate STDP in the human fronto-parietal network using paired associative stimulation (PAS).
• To determine if the dorsolateral prefrontal cortex (DLPFC) exhibits robust STDP.

Main Methods:

• Combined transcranial magnetic stimulation (TMS) with electroencephalography (EEG).
• Applied two PAS protocols (fronto-parietal and parieto-frontal) to modulate neural input timing.
• Measured TMS-evoked cortical activity and high-frequency oscillations.

Main Results:

• Demonstrated robust STDP in the human DLPFC.
• Observed long-term potentiation or depression of TMS-evoked activity following specific stimulation orders.
• Found sustained changes in high-frequency oscillatory activity correlating with STDP.

Conclusions:

• The human fronto-parietal network, particularly the DLPFC, supports STDP.
• Bidirectional synaptic plasticity can be induced via precisely timed fronto-parietal stimulation.
• Findings offer potential therapeutic avenues for enhancing plasticity in cognitive and psychiatric disorders.