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The effects of impulsivity and proactive inhibition on reactive inhibition and the go process: insights from vocal and manual stop signal tasks.

Castro-Meneses LJ, Johnson BW, Sowman PF - Front Hum Neurosci (2015)

Bottom Line: Our aim was to evaluate the effect stop probability would have on reactive and proactive inhibition.We tested 44 subjects and found that for the high compared to low probability stop signal condition, more proactive inhibition was evident and this was correlated with a reduction in the stop signal reaction time (SSRT).We found that reactive inhibition had a positive relationship with dysfunctional but not functional impulsivity in both vocal and manual domains of responding.

View Article: PubMed Central - PubMed

Affiliation: Department of Cognitive Science, Australian Research Council Centre of Excellence in Cognition and its Disorders, Macquarie University North Ryde, NSW, Australia ; Department of Cognitive Science, Perception in Action Research Centre, Macquarie University North Ryde, NSW, Australia.

ABSTRACT
This study measured proactive and reactive response inhibition and their relationships with self-reported impulsivity. We examined the domains of both vocal and manual responding using a stop signal task (SST) with two stop probabilities: high and low probability stop (1/3 and 1/6 stops respectively). Our aim was to evaluate the effect stop probability would have on reactive and proactive inhibition. We tested 44 subjects and found that for the high compared to low probability stop signal condition, more proactive inhibition was evident and this was correlated with a reduction in the stop signal reaction time (SSRT). We found that reactive inhibition had a positive relationship with dysfunctional but not functional impulsivity in both vocal and manual domains of responding. These findings support the hypothesis that proactive inhibition may pre-activate the network for reactive inhibition.

No MeSH data available.


Trial structure of the stop-signal task (SST). There were three main trial types: certain go, uncertain go and stop trials. Certain go trials were signaled by a blue circle and always required to either press a response button (manual-responses) or produce the short vowel sound “ɪ” as it would occur in the word “hit/hɪt/”(vocal-responses). Uncertain go trials were signaled by a yellow circle and required a response as in the certain go trials. Finally, stop trials started as uncertain go trials but after the stop signal delay (SSD), a stop-signal was presented, which was signaled by a purple circle. Participants were instructed to attempt to withhold their responses on seeing the stop signal. In the high probability stop condition, stop signals occurred following 2/3 of the uncertain go signals whereas in the low probability stop condition stop signals occurred following 1/3 of the uncertain go signals.
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Figure 1: Trial structure of the stop-signal task (SST). There were three main trial types: certain go, uncertain go and stop trials. Certain go trials were signaled by a blue circle and always required to either press a response button (manual-responses) or produce the short vowel sound “ɪ” as it would occur in the word “hit/hɪt/”(vocal-responses). Uncertain go trials were signaled by a yellow circle and required a response as in the certain go trials. Finally, stop trials started as uncertain go trials but after the stop signal delay (SSD), a stop-signal was presented, which was signaled by a purple circle. Participants were instructed to attempt to withhold their responses on seeing the stop signal. In the high probability stop condition, stop signals occurred following 2/3 of the uncertain go signals whereas in the low probability stop condition stop signals occurred following 1/3 of the uncertain go signals.

Mentions: This study implemented a variant of the stop-signal task or SST (Logan and Cowan, 1984; Logan, 1994). It contained three types of trials (certain go, uncertain go, and stop) that all occurred within every block. All trials began with a black fixation cross appearing in the center of a white background; the duration of fixation randomly varied between 1 and 2.5 s. Certain go trials consisted of a simple reaction time task where participants were required to respond as quickly as possible to the certain go-signal, which was indicated by the onset of a blue circle, 10.5 cm in diameter (see Figure 1) in the center of the monitor. Certain go trials made up 50% of the total trial number. For manual responses, participants were asked to press a response button as quickly as possible whereas for vocal responses, participants were asked to make the short vowel sound “ɪ” as it would occur in the word “hit/hɪt/.” The other half of the trials was uncertain go trials in which the onset of yellow circle was the signal to initiate a response. The uncertainty in this trial type was created by the possibility of a stop signal following the go signal (yellow circle). The stop signal could appear with a probability of either one third or two thirds of all uncertain go trials. Hereafter we refer to these as low probability and high probability stop signals respectively. Participants were required to respond to the yellow circle as if this was a blue circle unless the stop-signal appeared.


The effects of impulsivity and proactive inhibition on reactive inhibition and the go process: insights from vocal and manual stop signal tasks.

Castro-Meneses LJ, Johnson BW, Sowman PF - Front Hum Neurosci (2015)

Trial structure of the stop-signal task (SST). There were three main trial types: certain go, uncertain go and stop trials. Certain go trials were signaled by a blue circle and always required to either press a response button (manual-responses) or produce the short vowel sound “ɪ” as it would occur in the word “hit/hɪt/”(vocal-responses). Uncertain go trials were signaled by a yellow circle and required a response as in the certain go trials. Finally, stop trials started as uncertain go trials but after the stop signal delay (SSD), a stop-signal was presented, which was signaled by a purple circle. Participants were instructed to attempt to withhold their responses on seeing the stop signal. In the high probability stop condition, stop signals occurred following 2/3 of the uncertain go signals whereas in the low probability stop condition stop signals occurred following 1/3 of the uncertain go signals.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4594014&req=5

Figure 1: Trial structure of the stop-signal task (SST). There were three main trial types: certain go, uncertain go and stop trials. Certain go trials were signaled by a blue circle and always required to either press a response button (manual-responses) or produce the short vowel sound “ɪ” as it would occur in the word “hit/hɪt/”(vocal-responses). Uncertain go trials were signaled by a yellow circle and required a response as in the certain go trials. Finally, stop trials started as uncertain go trials but after the stop signal delay (SSD), a stop-signal was presented, which was signaled by a purple circle. Participants were instructed to attempt to withhold their responses on seeing the stop signal. In the high probability stop condition, stop signals occurred following 2/3 of the uncertain go signals whereas in the low probability stop condition stop signals occurred following 1/3 of the uncertain go signals.
Mentions: This study implemented a variant of the stop-signal task or SST (Logan and Cowan, 1984; Logan, 1994). It contained three types of trials (certain go, uncertain go, and stop) that all occurred within every block. All trials began with a black fixation cross appearing in the center of a white background; the duration of fixation randomly varied between 1 and 2.5 s. Certain go trials consisted of a simple reaction time task where participants were required to respond as quickly as possible to the certain go-signal, which was indicated by the onset of a blue circle, 10.5 cm in diameter (see Figure 1) in the center of the monitor. Certain go trials made up 50% of the total trial number. For manual responses, participants were asked to press a response button as quickly as possible whereas for vocal responses, participants were asked to make the short vowel sound “ɪ” as it would occur in the word “hit/hɪt/.” The other half of the trials was uncertain go trials in which the onset of yellow circle was the signal to initiate a response. The uncertainty in this trial type was created by the possibility of a stop signal following the go signal (yellow circle). The stop signal could appear with a probability of either one third or two thirds of all uncertain go trials. Hereafter we refer to these as low probability and high probability stop signals respectively. Participants were required to respond to the yellow circle as if this was a blue circle unless the stop-signal appeared.

Bottom Line: Our aim was to evaluate the effect stop probability would have on reactive and proactive inhibition.We tested 44 subjects and found that for the high compared to low probability stop signal condition, more proactive inhibition was evident and this was correlated with a reduction in the stop signal reaction time (SSRT).We found that reactive inhibition had a positive relationship with dysfunctional but not functional impulsivity in both vocal and manual domains of responding.

View Article: PubMed Central - PubMed

Affiliation: Department of Cognitive Science, Australian Research Council Centre of Excellence in Cognition and its Disorders, Macquarie University North Ryde, NSW, Australia ; Department of Cognitive Science, Perception in Action Research Centre, Macquarie University North Ryde, NSW, Australia.

ABSTRACT
This study measured proactive and reactive response inhibition and their relationships with self-reported impulsivity. We examined the domains of both vocal and manual responding using a stop signal task (SST) with two stop probabilities: high and low probability stop (1/3 and 1/6 stops respectively). Our aim was to evaluate the effect stop probability would have on reactive and proactive inhibition. We tested 44 subjects and found that for the high compared to low probability stop signal condition, more proactive inhibition was evident and this was correlated with a reduction in the stop signal reaction time (SSRT). We found that reactive inhibition had a positive relationship with dysfunctional but not functional impulsivity in both vocal and manual domains of responding. These findings support the hypothesis that proactive inhibition may pre-activate the network for reactive inhibition.

No MeSH data available.