Early changes in corticospinal excitability when seeing fearful body expressions

Sara Borgomaneri, Francesca Vitale, Alessio Avenanti

Research output: Contribution to journalArticlepeer-review


Quick inhibition of approach tendencies in response to signals of potential threats is thought to promote survival. However, little is known about the effect of viewing fearful expressions on the early dynamics of the human motor system. We used the high temporal resolution of single-pulse and paired-pulse transcranial magnetic stimulation (TMS) over the motor cortex to assess corticospinal excitability (CSE) and intracortical facilitation (ICF) during observation of happy, fearful and neutral body postures. To test motor circuits involved in approach tendencies, CSE and ICF were recorded from the first dorsal interosseous (FDI), a muscle involved in grasping, and the abductor pollicis brevis (APB), which served as a control. To test early motor dynamics, CSE and ICF were measured 70-90 €‰ms after stimulus onset. We found a selective reduction in CSE in the FDI when participants observed fearful body expressions. No changes in ICF or in the excitability of APB were detected. Our study establishes an extremely rapid motor system reaction to observed fearful body expressions. This motor modulation involves corticospinal downstream projections but not cortical excitatory mechanisms, and appears to reflect an inhibition of hand grasping. Our results suggest a fast visuo-motor route that may rapidly inhibit inappropriate approaching actions.

Original languageEnglish
Article number14122
JournalScientific Reports
Publication statusPublished - Sep 21 2015

ASJC Scopus subject areas

  • General


Dive into the research topics of 'Early changes in corticospinal excitability when seeing fearful body expressions'. Together they form a unique fingerprint.

Cite this