Suppressing a pending action is an essential ability when someone must cope with an unpredictable situation. This component of executive control has been extensively studied by the stop-signal task (SST). SST is a task requiring to respond with a movement to a go signal (go trials) but to refrain from the movement when occasionally a stop signal occurs after the go signal (stop trials). A theoretical model describes the outcome in stop trials as a race towards a threshold between a go and a stop process. Every time the go process runs faster than the stop process the movement cannot be interrupted (stop error trials). In addition, it has been hypothesized the go process as a two-stage process including: 1) a controlled stage (CS), that can be inhibited at any time; 2) a ballistic stage (BS), that cannot be inhibited. A point-of-no-return defines the crossing line between CS and BS. It has been reported that perceptual and cognitive variables can affect the duration of CS and influence the probability of the stop process to win the race. Besides these factors, for some effectors, the state of biomechanics variables could influence the start of the go process. For example, we can hypothesize that if we ask someone to push a button and then release it in response to a go signal, the strength applied to push the button at the beginning of a given trial could play a role in influencing the CS of button release and, consequently, the run of the go process against the stop process. Here we tested this hypothesis by studying 20 healthy volunteers performing a button release SST while monitoring the time evolution of CS by a force sensor resistor (FSR) fixed on a mouse button. The analysis of the perturbation of FSR revealed in a proportion of correctly stopped trials, defined as “partial errors”, an initial decline of the force applied on the button (as in go trials), followed by a rising back of it. This FSR pattern was never observed in stop error trials. Looking at the amount of force exerted on the button at the beginning of trials, it was significantly higher in partial error than in stop error trials, suggesting that trials started with an initial high force on the button have higher probability to turn in correct for higher differences between the force at the beginning of CS and that at the time of movement onset. Moreover, in partial errors the velocity of decay of the FSR signal was lower than in stop error trials, allowing subjects to stay within the CS for longer. These results point out that models of movement inhibition need to account for the biomechanical state of the effector before the go-signal.
Forcing the winning horse: how the amount of force on a push button affects the inhibition of finger release in a stop signal task / Colangeli, S.; Ramawat, S.; Marc, I. B.; Pani, P.; Ferraina, S.; Brunamonti, E. - (2021). (Intervento presentato al convegno Neuroscience 2021 50th Annual Meeting tenutosi a Chicago(Online)).
Forcing the winning horse: how the amount of force on a push button affects the inhibition of finger release in a stop signal task
Colangeli, S.Primo
;Ramawat, S.Secondo
;Marc, I. B.;Pani, P.;Ferraina, S.Penultimo
;Brunamonti, E
Ultimo
2021
Abstract
Suppressing a pending action is an essential ability when someone must cope with an unpredictable situation. This component of executive control has been extensively studied by the stop-signal task (SST). SST is a task requiring to respond with a movement to a go signal (go trials) but to refrain from the movement when occasionally a stop signal occurs after the go signal (stop trials). A theoretical model describes the outcome in stop trials as a race towards a threshold between a go and a stop process. Every time the go process runs faster than the stop process the movement cannot be interrupted (stop error trials). In addition, it has been hypothesized the go process as a two-stage process including: 1) a controlled stage (CS), that can be inhibited at any time; 2) a ballistic stage (BS), that cannot be inhibited. A point-of-no-return defines the crossing line between CS and BS. It has been reported that perceptual and cognitive variables can affect the duration of CS and influence the probability of the stop process to win the race. Besides these factors, for some effectors, the state of biomechanics variables could influence the start of the go process. For example, we can hypothesize that if we ask someone to push a button and then release it in response to a go signal, the strength applied to push the button at the beginning of a given trial could play a role in influencing the CS of button release and, consequently, the run of the go process against the stop process. Here we tested this hypothesis by studying 20 healthy volunteers performing a button release SST while monitoring the time evolution of CS by a force sensor resistor (FSR) fixed on a mouse button. The analysis of the perturbation of FSR revealed in a proportion of correctly stopped trials, defined as “partial errors”, an initial decline of the force applied on the button (as in go trials), followed by a rising back of it. This FSR pattern was never observed in stop error trials. Looking at the amount of force exerted on the button at the beginning of trials, it was significantly higher in partial error than in stop error trials, suggesting that trials started with an initial high force on the button have higher probability to turn in correct for higher differences between the force at the beginning of CS and that at the time of movement onset. Moreover, in partial errors the velocity of decay of the FSR signal was lower than in stop error trials, allowing subjects to stay within the CS for longer. These results point out that models of movement inhibition need to account for the biomechanical state of the effector before the go-signal.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.