Cortical Dynamics of Motivational Salience: TMS-EEG and ERP Integration in a Food Cue Paradigm

Abstract

Abstract Background & Objective

This study investigated the neural mechanisms underlying food-related motivational salience by integrating transcranial magnetic stimulation with electroencephalography (TMS–EEG) in a visual cue paradigm. By aligning TMS-evoked potentials (TEPs) with classical event-related potential (ERP) components, we aimed to characterize cortical excitability and inhibitory dynamics during early and sustained stages of stimulus processing. 

Methods 

TEPs were recorded over the left dorsolateral prefrontal cortex (DLPFC) at two latencies—immediately (0 ms) and 300 ms after the onset of food-related and neutral images. Thirty-nine participants were classified as high or normal cravers based on composite craving scores derived from questionnaire and visual analog ratings. 

Results

At 0 ms, high cravers exhibited greater early inhibitory (N40) and excitatory (P60) responses to food cues, together with enhanced N280 amplitudes, indicating stronger early cortical engagement. At 300 ms, larger P185 amplitudes reflected prolonged processing in high cravers. Within the high-craver group, P60 amplitudes were positively correlated with post-task craving ratings, suggesting a link between early cortical excitability and subjective motivational state. 

Conclusions 

These findings demonstrate that TMS–EEG can resolve temporally distinct neural signatures of excitatory and inhibitory processing in response to salient cues. The observed TEP patterns, particularly in components associated with GABAergic inhibition (N40, N100), reveal individual variability in prefrontal control of appetitive stimuli. By bridging ERP and TMS–EEG approaches, this study provides mechanistic insight into the temporal dynamics of prefrontal regulation under motivational challenge and identifies potential neurophysiological markers for targeted neuromodulation of cue reactivity in health and disorder. 

Keywords 

TMS-EEG Food craving Craving vulnerability Cue reactivity Cortical excitability Dorsolateral prefrontal cortex (DLPFC) Event-related potentials (ERP) State-dependent brain dynamics Inhibition and excitation Motivational salience

Authors

King, F.C., Ismail, F.Y., Statsenko, Y., Baylis, C. G., & Ljubisavljevic, M.