Inhibitory control of reaching movements in humans

Giovanni Mirabella, Pierpaolo Pani, Martin Paré, Stefano Ferraina

Research output: Contribution to journalArticlepeer-review

Abstract

Behavioral flexibility provides a very large repertoire of actions and strategies, however, it carries a cost: a potential interference between different options. The voluntary control of behavior starts exactly with the ability of deciding between alternatives. Certainly inhibition plays a key role in this process. Here we examined the inhibitory control of reaching arm movements with the countermanding paradigm. Right-handed human subjects were asked to perform speeded reaching movements toward a visual target appearing either on the same or opposite side of the reaching arm (no-stop trials), but to withhold the commanded movement whenever an infrequent stop signal was presented (stop trials). As the delay between go and stop signals increased, subjects increasingly failed to inhibit the movement. From this inhibitory function and the reaction times of movements in no-stop trials, we estimated the otherwise unobservable duration of the stopping process, the stop signal reaction time (SSRT). We found that the SSRT for reaching movements was, on average, 206 ms and that it varied with the reaching arm and the target position even though the stop signal was a central stimulus. In fact, subjects were always faster to withhold reaching movements toward visual targets appearing on the same side of the reaching arm. This behavior strictly parallels the course of the reaction times of no-stop trials. These data show that the stop and go processes interacting in this countermanding task are independent, but most likely influenced by a common factor when under the control of the same hemisphere. In addition, we show that the point beyond which the response cannot be inhibited, the so-called point-of-no-return that divides controlled and ballistic phases of movement processing, lies after the inter-hemispheric transfer.

Original languageEnglish
Pages (from-to)240-255
Number of pages16
JournalExperimental Brain Research
Volume174
Issue number2
DOIs
Publication statusPublished - Sep 2006

Keywords

  • Countermanding
  • Human
  • Motor control
  • Reaching

ASJC Scopus subject areas

  • Neuroscience(all)

Fingerprint Dive into the research topics of 'Inhibitory control of reaching movements in humans'. Together they form a unique fingerprint.

Cite this