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Proactive and reactive control by the medial frontal cortex.

Stuphorn V, Emeric EE - Front Neuroeng (2012)

Bottom Line: This can occur either proactively to anticipate task requirements, or reactively in response to sudden changes.However, due to technical limitations, such as the spatial and temporal resolution of the BOLD signal, human imaging experiments are not able to disambiguate the specific function(s) of these brain regions.These limitations can be overcome through single-unit recordings in non-human primates.

View Article: PubMed Central - PubMed

Affiliation: Psychological and Brain Sciences, The Zanvyl Krieger Mind/Brain Institute, Johns Hopkins University, Baltimore MD, USA.

ABSTRACT
Adaptive behavior requires the ability to flexibly control actions. This can occur either proactively to anticipate task requirements, or reactively in response to sudden changes. Recent work in humans has identified a network of cortical and subcortical brain region that might have an important role in proactive and reactive control. However, due to technical limitations, such as the spatial and temporal resolution of the BOLD signal, human imaging experiments are not able to disambiguate the specific function(s) of these brain regions. These limitations can be overcome through single-unit recordings in non-human primates. In this article, we describe the behavioral and physiological evidence for dual mechanisms of control in response inhibition in the medial frontal cortex of monkeys performing the stop signal or countermanding task.

No MeSH data available.


Changes in LFP power predict arm movement inhibition. Effects of trial history on response time. (A) Response times for no-stop-signal and stop trials surrounding noncanceled trials (left), trials surrounding canceled trials (middle), and trials surrounding corrected trials (right). The type of trials to which the response time corresponds to is shown in bold (G: no stop signal; E: noncanceled; Ca: canceled; Co: corrected). The dotted line indicates the average response time on no-stop-signal trials. (B) Effects of trial history on LFP power in the SMA. Comparison was performed between three groups of no-stop-signal trials: those that followed another canceled trial (Ca-Go), those that followed anoncanceled error trial (E-Go), and those that followed a go trial (Go-Go). The time-frequency maps are aligned on target onset. The significant differences between them are shown in the right panel.
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Figure 3: Changes in LFP power predict arm movement inhibition. Effects of trial history on response time. (A) Response times for no-stop-signal and stop trials surrounding noncanceled trials (left), trials surrounding canceled trials (middle), and trials surrounding corrected trials (right). The type of trials to which the response time corresponds to is shown in bold (G: no stop signal; E: noncanceled; Ca: canceled; Co: corrected). The dotted line indicates the average response time on no-stop-signal trials. (B) Effects of trial history on LFP power in the SMA. Comparison was performed between three groups of no-stop-signal trials: those that followed another canceled trial (Ca-Go), those that followed anoncanceled error trial (E-Go), and those that followed a go trial (Go-Go). The time-frequency maps are aligned on target onset. The significant differences between them are shown in the right panel.

Mentions: While the experimental evidence in favor of a role of the medial frontal cortex in reactive control was mixed, there is very clear evidence for such a role in the case of proactive control. Very few neurons carried signals sufficient for saccade initiation (Stuphorn et al., 2010). However, there exists a more subtle relationship between SEF activation and saccade production. The activity of some SEF neurons was correlated with response time and varied with sequential adjustments in response latency. Trials in which monkeys inhibited or produced a saccade in a stop signal trial were distinguished by a modest difference in discharge rate of these SEF neurons before stop signal or target presentation. Parallel results were observed in the SMA (Chen et al., 2010). Furthermore, the analysis of LFP in the SMA showed that longer response times following stop signal trials (Figure 3A) were accompanied by an increased power in the very low-frequency (1–20 Hz) and the beta band (25–40 Hz) starting approximately 120 ms before target onset (Figure 3B). These findings indicate that neurons in the SEF and pre-SMA/SMA, in contrast to FEF/SC movement and fixation cells, do not contribute directly and immediately to the initiation of visually guided saccades. However the SEF, pre-SMA, and SMA may proactively regulate movement initiation by adjusting the level of excitation and inhibition of the occulomotor and skeletomotor systems based on prior performance and anticipated task requirements.


Proactive and reactive control by the medial frontal cortex.

Stuphorn V, Emeric EE - Front Neuroeng (2012)

Changes in LFP power predict arm movement inhibition. Effects of trial history on response time. (A) Response times for no-stop-signal and stop trials surrounding noncanceled trials (left), trials surrounding canceled trials (middle), and trials surrounding corrected trials (right). The type of trials to which the response time corresponds to is shown in bold (G: no stop signal; E: noncanceled; Ca: canceled; Co: corrected). The dotted line indicates the average response time on no-stop-signal trials. (B) Effects of trial history on LFP power in the SMA. Comparison was performed between three groups of no-stop-signal trials: those that followed another canceled trial (Ca-Go), those that followed anoncanceled error trial (E-Go), and those that followed a go trial (Go-Go). The time-frequency maps are aligned on target onset. The significant differences between them are shown in the right panel.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC3378012&req=5

Figure 3: Changes in LFP power predict arm movement inhibition. Effects of trial history on response time. (A) Response times for no-stop-signal and stop trials surrounding noncanceled trials (left), trials surrounding canceled trials (middle), and trials surrounding corrected trials (right). The type of trials to which the response time corresponds to is shown in bold (G: no stop signal; E: noncanceled; Ca: canceled; Co: corrected). The dotted line indicates the average response time on no-stop-signal trials. (B) Effects of trial history on LFP power in the SMA. Comparison was performed between three groups of no-stop-signal trials: those that followed another canceled trial (Ca-Go), those that followed anoncanceled error trial (E-Go), and those that followed a go trial (Go-Go). The time-frequency maps are aligned on target onset. The significant differences between them are shown in the right panel.
Mentions: While the experimental evidence in favor of a role of the medial frontal cortex in reactive control was mixed, there is very clear evidence for such a role in the case of proactive control. Very few neurons carried signals sufficient for saccade initiation (Stuphorn et al., 2010). However, there exists a more subtle relationship between SEF activation and saccade production. The activity of some SEF neurons was correlated with response time and varied with sequential adjustments in response latency. Trials in which monkeys inhibited or produced a saccade in a stop signal trial were distinguished by a modest difference in discharge rate of these SEF neurons before stop signal or target presentation. Parallel results were observed in the SMA (Chen et al., 2010). Furthermore, the analysis of LFP in the SMA showed that longer response times following stop signal trials (Figure 3A) were accompanied by an increased power in the very low-frequency (1–20 Hz) and the beta band (25–40 Hz) starting approximately 120 ms before target onset (Figure 3B). These findings indicate that neurons in the SEF and pre-SMA/SMA, in contrast to FEF/SC movement and fixation cells, do not contribute directly and immediately to the initiation of visually guided saccades. However the SEF, pre-SMA, and SMA may proactively regulate movement initiation by adjusting the level of excitation and inhibition of the occulomotor and skeletomotor systems based on prior performance and anticipated task requirements.

Bottom Line: This can occur either proactively to anticipate task requirements, or reactively in response to sudden changes.However, due to technical limitations, such as the spatial and temporal resolution of the BOLD signal, human imaging experiments are not able to disambiguate the specific function(s) of these brain regions.These limitations can be overcome through single-unit recordings in non-human primates.

View Article: PubMed Central - PubMed

Affiliation: Psychological and Brain Sciences, The Zanvyl Krieger Mind/Brain Institute, Johns Hopkins University, Baltimore MD, USA.

ABSTRACT
Adaptive behavior requires the ability to flexibly control actions. This can occur either proactively to anticipate task requirements, or reactively in response to sudden changes. Recent work in humans has identified a network of cortical and subcortical brain region that might have an important role in proactive and reactive control. However, due to technical limitations, such as the spatial and temporal resolution of the BOLD signal, human imaging experiments are not able to disambiguate the specific function(s) of these brain regions. These limitations can be overcome through single-unit recordings in non-human primates. In this article, we describe the behavioral and physiological evidence for dual mechanisms of control in response inhibition in the medial frontal cortex of monkeys performing the stop signal or countermanding task.

No MeSH data available.