Causal evidence for lateral prefrontal cortex dynamics supporting cognitive control

The lateral prefrontal cortex (LPFC) is essential for higher-level cognition, but the nature of its interactions in supporting cognitive control remains elusive. Previously (Nee and D'Esposito, 2016), dynamic causal modeling (DCM) indicated that mid LPFC integrates abstract, rostral and concrete, caudal influences to inform context-appropriate action. Here, we use continuous theta-burst transcranial magnetic stimulation (cTBS) to test this model causally. cTBS was applied to three LPFC sites and a control site in counterbalanced sessions. Behavioral modulations resulting from cTBS were largely predicted by information flow within the previously estimated DCM. However, cTBS to caudal LPFC unexpectedly impaired processes that are presumed to involve rostral LPFC. Adding a pathway from caudal to mid-rostral LPFC significantly improved the model fit and accounted for the observed behavioral findings. These data provide causal evidence for LPFC dynamics supporting cognitive control and demonstrate the utility of combining DCM with causal manipulations to test and refine models of cognition.

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Causal Evidence for Lateral Prefrontal Cortex Dynamics Supporting Cognitive Control

10.1101/130096 ◽

2017 ◽

Author(s):

Derek Evan Nee ◽

Mark D’Esposito

Keyword(s):

Prefrontal Cortex ◽

Transcranial Magnetic Stimulation ◽

Cognitive Control ◽

Magnetic Stimulation ◽

Control Site ◽

Causal Modeling ◽

Fmri Data ◽

Dynamic Causal Modeling ◽

Lateral Prefrontal Cortex ◽

Theta Burst

AbstractThe lateral prefrontal cortex (LPFC) is essential for higher-level cognition, but how interactions among LPFC areas support cognitive control has remained elusive. In previous work, dynamic causal modeling (DCM) of fMRI data revealed that demands on cognitive control elicited a convergence of influences towards mid LPFC. We proposed that these findings reflect the integration of abstract, rostral and concrete, caudal influences to inform context-appropriate action. Here, we provide a causal test of this model using continuous theta-burst transcranial magnetic stimulation (cTBS). cTBS was applied to caudal, mid, or rostral LPFC, as well as a control site in counterbalanced sessions. In most cases, behavioral modulations resulting from cTBS could be predicted based upon the direction of influences within the previously estimated DCM. However, inconsistent with our DCM, we found that cTBS to caudal LPFC impaired cognitive control processes presumed to involve rostral LPFC. Revising the original DCM with a pathway from caudal LPFC to rostral LPFC significantly improved the fitted DCM and accounted for the observed behavioral findings. These data provide causal evidence for LPFC dynamics supporting cognitive control and demonstrate the utility of combining DCM with causal manipulations to create, test, and refine models of cognition.

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P217 Disrupting cognitive control in dual-task situations by transcranial magnetic stimulation of the lateral prefrontal cortex

Clinical Neurophysiology ◽

10.1016/j.clinph.2016.10.334 ◽

2017 ◽

Vol 128 (3) ◽

pp. e119 ◽

Cited By ~ 1

Author(s):

S. Kübler ◽

T. Schubert

Keyword(s):

Prefrontal Cortex ◽

Transcranial Magnetic Stimulation ◽

Cognitive Control ◽

Dual Task ◽

Magnetic Stimulation ◽

Lateral Prefrontal Cortex ◽

Stimulation Of

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The hierarchical organization of the lateral prefrontal cortex

eLife ◽

10.7554/elife.12112 ◽

2016 ◽

Vol 5 ◽

Cited By ~ 62

Author(s):

Derek Evan Nee ◽

Mark D'Esposito

Keyword(s):

Prefrontal Cortex ◽

Functional Organization ◽

Relative Strength ◽

Causal Modeling ◽

Hierarchical Organization ◽

Dynamic Causal Modeling ◽

Cognitive Demands ◽

Lateral Prefrontal Cortex ◽

Hierarchical Processing ◽

Control Behavior

Higher-level cognition depends on the lateral prefrontal cortex (LPFC), but its functional organization has remained elusive. An influential proposal is that the LPFC is organized hierarchically whereby progressively rostral areas of the LPFC process/represent increasingly abstract information facilitating efficient and flexible cognition. However, support for this theory has been limited. Here, human fMRI data revealed rostral/caudal gradients of abstraction in the LPFC. Dynamic causal modeling revealed asymmetrical LPFC interactions indicative of hierarchical processing. Contrary to dominant assumptions, the relative strength of efferent versus afferent connections positioned mid LPFC as the apex of the hierarchy. Furthermore, cognitive demands induced connectivity modulations towards mid LPFC consistent with a role in integrating information for control operations. Moreover, the strengths of these dynamics were related to trait-measured higher-level cognitive ability. Collectively, these results suggest that the LPFC is hierarchically organized with the mid LPFC positioned to synthesize abstract and concrete information to control behavior.

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