Hierarchically Organized Medial Frontal Cortex-Basal Ganglia Loops Selectively Control Task- and Response-Selection

Abstract This EEG study investigates the electrophysiological activity underlying processes of stimulus and response selection, and their executive orchestration via long-range functional connectivity under conflict condition, in order to shed more light on how these brain dynamics shape individual behavioral performance. Participants (n = 91) performed a modified flanker task, in which bilateral visual stimulation and a bimanual response pattern were employed to isolate the stimulus and response selection-related lateralized activity. First, we identified conflict-related markers of task-relevant processes; most importantly, the stimulus and response selection were evidenced by contra–ipsilateral differences in visual and motor activity, respectively, and executive control was evidenced by modulations of midfrontal activity. Second, we identified conflict-related functional connectivity between midfrontal and other task-relevant areas. The results showed that interregional phase synchronization in theta band was centered at the midfrontal site, interpreted here as a “hub” of executive communication. Importantly, the theta functional connectivity was more robust under the condition of increased demands for stimulus and response selection, including connectivity between the medial frontal cortex and the lateral frontal and motor areas, as well as cross-frequency theta–alpha coupling between the medial frontal cortex and contralateral visual areas. Third, we showed that individual differences in the measured conflict-related EEG activity, particularly the midfrontal N2, theta power, and global theta connectivity, predict the behavioral efficiency in conflict resolution.

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Interference with Performance of a Response Selection Task that has no Working Memory Component: An rTMS Comparison of the Dorsolateral Prefrontal and Medial Frontal Cortex

Journal of Cognitive Neuroscience ◽

10.1162/089892901753294392 ◽

2001 ◽

Vol 13 (8) ◽

pp. 1097-1108 ◽

Cited By ~ 84

Author(s):

K. A. Hadland ◽

M. F. S. Rushworth ◽

R. E. Passingham ◽

M. Jahanshahi ◽

J. C. Rothwell

Keyword(s):

Working Memory ◽

Frontal Cortex ◽

Response Times ◽

Memory Load ◽

Response Selection ◽

Repetitive Transcranial Magnetic Stimulation ◽

Selection Task ◽

Medial Frontal Cortex ◽

Memory Element ◽

Dorsolateral Prefrontal

It has been suggested that the dorsolateral prefrontal cortex (DLPFC) is involved in free selection (FS), the process by which subjects themselves decide what action to perform. Evidence for this proposal has been provided by imaging studies showing activation of the DLPFC when subjects randomly generate responses. However, these response selection tasks have a hidden working memory element and it has been widely reported that the DLPFC is activated when subjects perform tasks which involve working memory. The primary aim of this experiment was to establish if the DLPFC is genuinely involved in response selection. We used repetitive transcranial magnetic stimulation (rTMS) to investigate whether temporary interference of the DLPFC could disrupt performance of a response selection task that had no working memory component. Subjects performed tasks in which they made bimanual sequences of eight nonrepeating finger movements. In the FS task, subjects chose their movements at random while a computer monitor displayed these moves. This visual feedback obviated the need for subjects to maintain their previous moves “on-line.” No selection was required for the two control tasks as responses were cued by the visual display. The attentional demands of the control tasks varied. In the high load (HL) version, subjects had to maintain their attention throughout the sequence, but this requirement was absent in the low load (LL) task. rTMS over the DLPFC slowed response times on the FS task and at the end of the sequence on the HL task, but had no effect on the LL task. rTMS over the medial frontal cortex (MFC) slowed response times on the FS task but had no effect on the HL task. This suggests that a response selection task without a working memory load will depend on the DLPFC and the MFC. The difference appears to be that the DLPFC is important when selecting between competing responses or when concentrating if there is a high attentional demand, but that the MFC is only important during the response selection task.

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Role of the Human Medial Frontal Cortex in Task Switching: A Combined fMRI and TMS Study

Journal of Neurophysiology ◽

10.1152/jn.2002.87.5.2577 ◽

2002 ◽

Vol 87 (5) ◽

pp. 2577-2592 ◽

Cited By ~ 316

Author(s):

M.F.S. Rushworth ◽

K. A. Hadland ◽

T. Paus ◽

P. K. Sipila

Keyword(s):

Frontal Cortex ◽

Task Switching ◽

Response Selection ◽

Repetitive Transcranial Magnetic Stimulation ◽

Blood Oxygenation ◽

Cortical Activation ◽

Medial Frontal Cortex ◽

Stimulus Selection ◽

Task Set ◽

Fmri Session

We used event-related functional magnetic resonance imaging (fMRI) to measure brain activity when subjects were performing identical tasks in the context of either a task-set switch or a continuation of earlier performance. The context, i.e., switching or staying with the current task, influenced medial frontal cortical activation; the medial frontal cortex is transiently activated at the time that subjects switch from one way of performing a task to another. Two types of task-set-switching paradigms were investigated. In the response-switching (RS) paradigm, subjects switched between different rules for response selection and had to choose between competing responses. In the visual-switching (VS) paradigm, subjects switched between different rules for stimulus selection and had to choose between competing visual stimuli. The type of conflict, sensory (VS) or motor (RS), involved in switching was critical in determining medial frontal activation. Switching in the RS paradigm was associated with clear blood-oxygenation-level-dependent signal increases (“activations”) in three medial frontal areas: the rostral cingulate zone, the caudal cingulate zone, and the presupplementary motor area (pre-SMA). Switching in the VS task was associated with definite activation in just one medial frontal area, a region on the border between the pre-SMA and the SMA. Subsequent to the fMRI session, we used MRI-guided frameless stereotaxic procedures and repetitive transcranial magnetic stimulation (rTMS) to test the importance of the medial frontal activations for task switching. Applying rTMS over the pre-SMA disrupted subsequent RS performance but only when it was applied in the context of a switch. This result shows, first, that the pre-SMA is essential for task switching and second that its essential role is transient and limited to just the time of behavioral switching. The results are consistent with a role for the pre-SMA in selecting between response sets at a superordinate level rather than in selecting individual responses. The effect of the rTMS was not simply due to the tactile and auditory artifacts associated with each pulse; rTMS over several control regions did not selectively disrupt switching. Applying rTMS over the SMA/pre-SMA area activated in the VS paradigm did not disrupt switching. This result, first, confirms the limited importance of the medial frontal cortex for sensory attentional switching. Second, the VS rTMS results suggest that just because an area is activated in two paradigms does not mean that it plays the same essentialrole in both cases.

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Transcranial direct current stimulation of superior medial frontal cortex disrupts response selection during proactive response inhibition

NeuroImage ◽

10.1016/j.neuroimage.2016.10.035 ◽

2017 ◽

Vol 158 ◽

pp. 455-465 ◽

Cited By ~ 6

Author(s):

Angela D. Bender ◽

Hannah L. Filmer ◽

Paul E. Dux

Keyword(s):

Frontal Cortex ◽

Direct Current ◽

Response Inhibition ◽

Transcranial Direct Current Stimulation ◽

Response Selection ◽

Medial Frontal Cortex ◽

Direct Current Stimulation ◽

Stimulation Of

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Synergistic information in the frontal cortex-striatal pathway

10.1101/2021.06.18.449072 ◽

2021 ◽

Author(s):

Ibrahim Alsolami ◽

Takashi Handa ◽

Tomoki Fukai

Keyword(s):

Decision Making ◽

Basal Ganglia ◽

Frontal Cortex ◽

Information Transfer ◽

Dorsal Striatum ◽

Brain Regions ◽

Medial Frontal Cortex ◽

Positive Interaction

Across the cortico-basal ganglia circuit, the medial frontal cortex (MFC) communicates with the dorsal striatum (DS) during learning and planning. How these two brain regions communicate with each other is, however, not fully understood. Here we report the presence of synergistic information during information transfer across the frontal cortex-striatal pathway. Synergistic information emerges from the positive interaction of DS and MFC neurons and provides the DS with additional cortical information. This information is held latent in neuronal signals. To reveal it, we simultaneously record neuronal activities from the MFC and DS of rats trained on an outcome-based decision-making task and determined whether past neuronal activities of the DS positively influence communication rates. We detect a neuronal synergy that enables the MFC to boost its communication rate to the DS. Our results suggest that past neuronal activities of the DS are not redundant but play a key communication role in the MFC-DS network.

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Transcortical Motor Aphasia

10.1093/oxfordhb/9780199772391.013.11 ◽

2015 ◽

Author(s):

Bruce A. Crosson ◽

Anastasia Ford ◽

Anastasia M. Raymer

Keyword(s):

Basal Ganglia ◽

Frontal Cortex ◽

Language Production ◽

Right Hemisphere ◽

Premotor Cortex ◽

Medial Frontal Cortex ◽

Positive Effects ◽

Motor Aphasia ◽

Dopaminergic Pathways ◽

Verbal Output

The defining symptoms of transcortical motor aphasia (TCMA) are nonfluent verbal output with relatively preserved repetition. Other symptoms, such as naming difficulties, agrammatic output, or even some paraphasias, may occur, but these are not cardinal symptoms defining TCMA and are not necessary for the diagnosis. The core anatomy involved in TCMA is a lesion of the medial frontal cortex, especially the left presupplementary motor area (pre-SMA) and adjacent Brodmann’s area 32; a lesion of the left posterior inferior frontal cortex, especially pars opercularis and ventral lateral premotor cortex; or a lesion of the pathways between these frontal structures. TCMA occasionally has been reported with a lesion of the left basal ganglia, the left thalamus, or the ascending dopaminergic pathways. From a cognitive standpoint, TCMA can be conceptualized as a disorder of intention, in other words, as a disorder of initiation and continuation of spoken language that is internally motivated. The medial frontal cortex provides the impetus to speak; this impetus to speak is conveyed to lateral frontal structures through frontal–subcortical pathways where it activates various language production mechanisms. The influence of the ascending dopaminergic pathways may occur either through their heavy connections with the pre-SMA region or through their influence on the basal ganglia. The influence of the basal ganglia and thalamus probably occurs through their connections with the medial frontal cortex. Assessments for TCMA should involve a thorough evaluation of conversational or narrative language output and repetition. New treatments are available that attempt to engage right-hemisphere intention mechanisms with left-hand movements and may be effective in TCMA. Although dopamine agonists have also shown some positive effects in increasing verbal output in TCMA, trials have been small, and some caution must be exercised in interpreting these findings.

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