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Putting the brakes on inhibitory models of frontal lobe function.

Hampshire A - Neuroimage (2015)

Bottom Line: However, there is growing evidence to support the alternative view that response inhibition is just one prominent example of the many cognitive control processes that are supported by the same set of 'domain general' functional networks.The results demonstrate that there is no inhibitory module within the RIFC.Instead, response inhibition recruits a functionally heterogeneous ensemble of RIFC networks, which can be dissociated from each other in the context of other task demands.

View Article: PubMed Central - PubMed

Affiliation: The Computational, Cognitive and Clinical Neuroimaging Laboratory, Division of Brain Sciences, Imperial College London, London, United Kingdom. Electronic address: a.hampshire@imperial.ac.uk.

No MeSH data available.


(a) In the stop signal task, participants are instructed to respond as quickly and accurately as possible to ‘go’ stimuli in the form of left and right arrows, which are presented in a rapid and pseudo-randomised sequence. During the inhibition trials, they must try to cancel the already initiated response when an infrequent stop signal cue is presented at a short offset after the go cue. The go–stop offset is typically set to produce a 50% failure rate on the inhibition trials. (b) In the target detection paradigm, participants are instructed to monitor sequences of distractors for an infrequent target stimulus. The stimulus that is the target is periodically changed. When motor responses are made to distractors but not to targets, this design is equivalent to a go–no go paradigm.
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f0005: (a) In the stop signal task, participants are instructed to respond as quickly and accurately as possible to ‘go’ stimuli in the form of left and right arrows, which are presented in a rapid and pseudo-randomised sequence. During the inhibition trials, they must try to cancel the already initiated response when an infrequent stop signal cue is presented at a short offset after the go cue. The go–stop offset is typically set to produce a 50% failure rate on the inhibition trials. (b) In the target detection paradigm, participants are instructed to monitor sequences of distractors for an infrequent target stimulus. The stimulus that is the target is periodically changed. When motor responses are made to distractors but not to targets, this design is equivalent to a go–no go paradigm.

Mentions: The design of study 1 has been reported in detail in a previous article in this journal (Hampshire et al., 2010); in brief, there were three blocks of scanning acquisition during which participants undertook a classic SST paradigm and two attentional control variants of the task. In all three of the acquisition blocks, participants viewed a series of left and right arrows that appeared on the screen in rapid succession. Less frequently, an up arrow appeared a short variable delay after the onset of the left or right arrow (Fig. 1a), and this formed the cue for an additional behaviour that varied across the three blocks. During the first block, participants were instructed to silently count the total number of up-arrow cues that were presented without making any motor responses (‘COUNT’). At the end of the block, participants were asked to report the total number of up arrows that they had counted. In the second block (RESPOND), participants responded to the up-arrow cue with a left or right button press the direction of which was defined by the immediately preceding lateral arrow. In the third block, participants were instructed to make left or right button presses as soon as possible after the appearance of the left and right arrows, but to try and cancel that response whenever an up arrow was presented (‘INHIBIT’). This latter condition was equivalent to the response inhibition manipulation employed in classical SST tasks. Participants viewed a total of 131 left and 131 right arrows per 9-min acquisition block, 68 of which were followed by up arrows. Left and right arrows were displayed on the screen for 300 ms with a predefined pseudo-randomised ISI such that arrows occurred at either 1600, 1700, 1800, 1900 or 2000 ms intervals. Up arrows were displayed unpredictably after the left and right arrows with a predefined and pseudo-randomised offset from the start of the left or right signal of between 300 and 900 ms.


Putting the brakes on inhibitory models of frontal lobe function.

Hampshire A - Neuroimage (2015)

(a) In the stop signal task, participants are instructed to respond as quickly and accurately as possible to ‘go’ stimuli in the form of left and right arrows, which are presented in a rapid and pseudo-randomised sequence. During the inhibition trials, they must try to cancel the already initiated response when an infrequent stop signal cue is presented at a short offset after the go cue. The go–stop offset is typically set to produce a 50% failure rate on the inhibition trials. (b) In the target detection paradigm, participants are instructed to monitor sequences of distractors for an infrequent target stimulus. The stimulus that is the target is periodically changed. When motor responses are made to distractors but not to targets, this design is equivalent to a go–no go paradigm.
© Copyright Policy - CC BY-NC-ND
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4441092&req=5

f0005: (a) In the stop signal task, participants are instructed to respond as quickly and accurately as possible to ‘go’ stimuli in the form of left and right arrows, which are presented in a rapid and pseudo-randomised sequence. During the inhibition trials, they must try to cancel the already initiated response when an infrequent stop signal cue is presented at a short offset after the go cue. The go–stop offset is typically set to produce a 50% failure rate on the inhibition trials. (b) In the target detection paradigm, participants are instructed to monitor sequences of distractors for an infrequent target stimulus. The stimulus that is the target is periodically changed. When motor responses are made to distractors but not to targets, this design is equivalent to a go–no go paradigm.
Mentions: The design of study 1 has been reported in detail in a previous article in this journal (Hampshire et al., 2010); in brief, there were three blocks of scanning acquisition during which participants undertook a classic SST paradigm and two attentional control variants of the task. In all three of the acquisition blocks, participants viewed a series of left and right arrows that appeared on the screen in rapid succession. Less frequently, an up arrow appeared a short variable delay after the onset of the left or right arrow (Fig. 1a), and this formed the cue for an additional behaviour that varied across the three blocks. During the first block, participants were instructed to silently count the total number of up-arrow cues that were presented without making any motor responses (‘COUNT’). At the end of the block, participants were asked to report the total number of up arrows that they had counted. In the second block (RESPOND), participants responded to the up-arrow cue with a left or right button press the direction of which was defined by the immediately preceding lateral arrow. In the third block, participants were instructed to make left or right button presses as soon as possible after the appearance of the left and right arrows, but to try and cancel that response whenever an up arrow was presented (‘INHIBIT’). This latter condition was equivalent to the response inhibition manipulation employed in classical SST tasks. Participants viewed a total of 131 left and 131 right arrows per 9-min acquisition block, 68 of which were followed by up arrows. Left and right arrows were displayed on the screen for 300 ms with a predefined pseudo-randomised ISI such that arrows occurred at either 1600, 1700, 1800, 1900 or 2000 ms intervals. Up arrows were displayed unpredictably after the left and right arrows with a predefined and pseudo-randomised offset from the start of the left or right signal of between 300 and 900 ms.

Bottom Line: However, there is growing evidence to support the alternative view that response inhibition is just one prominent example of the many cognitive control processes that are supported by the same set of 'domain general' functional networks.The results demonstrate that there is no inhibitory module within the RIFC.Instead, response inhibition recruits a functionally heterogeneous ensemble of RIFC networks, which can be dissociated from each other in the context of other task demands.

View Article: PubMed Central - PubMed

Affiliation: The Computational, Cognitive and Clinical Neuroimaging Laboratory, Division of Brain Sciences, Imperial College London, London, United Kingdom. Electronic address: a.hampshire@imperial.ac.uk.

No MeSH data available.