Previous transcranial magnetic stimulation (TMS) studies indicate that exposing the subjects to an emotionally valent stimulus results in larger motor evoked potentials (MEP). Up to date, no TMS studies have been conducted in order to investigate the effect of personal memories with emotional value on corticospinal excitability.

To investigate changes in corticospinal excitability and sensorimotor integration induced by retrieval of negative or neutral autobiographical memories (AM).

To contribute to a further characterization of neural circuits involved during the evocation of negative AM.

In 12 healthy volunteers, we recorded motor evoked potentials (MEPs) elicited by TMS pulses during the retrieval of negative AM or neutral AM. Furthermore, we also tested Short-interval Intracortical Inhibition (SICI), Intracortical facilitation (ICF), Short and Long afferent Inhibition (SAI and LAI) in the two different experimental conditions.

Retrieval of negative AM induced a larger increase in MEP amplitude (35.01%) compared to neutral AM (F(1,22) = 7.04, P = 0.013). Furthermore we showed that retrieval of Negative AM increasedn ICF (F(1,22) = 5, P = 0.03) and decrease SAI (F(1,22) = 7.04, P = 0.039). The other TMS parameters were different between conditions.

Our results indicate that evocation of negative AM induce a complex modulation of excitatory and inhibitory sensorimotor networks. Further studies are needed to explore the link of these electrophysiological biomarkers with the strength, valence and specificity of negative AM.

The authors have not supplied their declaration of competing interest.