Flexible brain network reconfiguration supporting inhibitory control

Abstract

The ability to inhibit distracting stimuli from interfering with goaldirected behavior is crucial for success in most spheres of life. Despite an abundance of studies examining regional brain activation, knowledge of the brain networks involved in inhibitory control remains quite limited. To address this critical gap, we applied graph theory tools to functional magnetic resonance imaging data collected while a large sample of adults (n = 101) performed a color-word Stroop task. Higher demand for inhibitory control was associated with restructuring of the global network into a configuration that was more optimized for specialized processing (functional segregation), more efficient at communicating the output of such processing across the network (functional integration), and more resilient to potential interruption (resilience). In addition, there were regional changes with right inferior frontal sulcus and right anterior insula occupying more central positions as network hubs, and dorsal anterior cingulate cortex becoming more tightly coupled with its regional subnetwork. Given the crucial role of inhibitory control in goal-directed behavior, present findings identifying functional network organization supporting inhibitory control have the potential to provide additional insights into how inhibitory control may break down in a wide variety of individuals with neurological or psychiatric difficulties. T he ability to exert cognitive control to inhibit distracting stimuli from interfering with goal-directed behavior is crucial for success in most spheres of life, including academic, occupational, health, and general well-being (1). However, such control is impaired under certain conditions in both psychologically/neurologically typical individuals [e.g., overeating during stressful periods (2)] and those with pathological conditions [e.g., addiction (3)]. Consequently, understanding the neural circuitry supporting inhibitory aspects of cognitive control has the potential to provide key insights into a wide array of difficulties, ranging from common activities of daily life to psychiatric disorders.Substantial uncertainty remains regarding the neurobiology supporting inhibitory aspects of cognitive control (4), with the majority of recent research focusing on which particular regions of prefrontal cortex (PFC) are important for which specific aspects of inhibitory control. A large body of research has identified a set of brain regions that appear generally crucial for inhibitory control. For example, consistent activation was identified in several critical regions in a recent meta-analysis of studies using the color-word Stroop (5), which is a classic cognitive control probe (6) and which we use in the present study. This task indexes inhibitory control, because an individual must maintain a task set in the face of irrelevant, but prepotent, information that must be inhibited. The meta-analysis revealed a number of regions, including dorsal anterior cingulate cortex (dACC), lateral PFC (e.g., BA 9/44/45/46), insul...

State-dependent variability of dynamic functional connectivity between frontoparietal and default networks relates to cognitive flexibility

“…Previous studies focusing on static connectivity alone have already pointed out that the interactions between the FPN and DMN are highly complex and may even change during a single task (Hellyer et al, 2014; Hearne et al, 2015; Piccoli et al, 2015), rendering FPN-DMN vdFC (as opposed to dynamics of one network by itself, for instance) of great importance for the direction of correlation. The FPN is generally considered a ‘task-positive’ network, while the DMN is down-regulated more strongly as cognitive load increases (Rosazza and Minati, 2011; Anticevic et al, 2012; Hugdahl et al, 2015; Spielberg et al, 2015). This state-dependent functionality has been hypothesized to be due to the balance between activation and inhibition.…”

Maturation trajectories of cortical resting-state networks depend on the mediating frequency band

“…We chose this measure because it has been studied, mostly using fMRI, in the context of psychiatric disorders, where multiple hubs might be functioning abnormally (Achard et al, 2006; Lo et al, 2015). It has also been shown that greater resilience in a functionally derived task-driven network is associated with greater inhibitory control cognitively (Spielberg et al, 2015), a function that is often impaired in neurodevelopmental and psychiatric disorders. Importantly, the measure incorporates network topology in conjunction with the spatial distribution of hubs, because it takes the degree, i.e.…”

From regions to connections and networks: new bridges between brain and behavior

“…Interest in modeling inter-regional connectivity has driven the development of new statistical techniques, as well as the application of established techniques from other fields [15*], including structural equation modeling, partial least squares, psychophysiological interactions and dynamic causal modeling. These techniques have demonstrated that functional interactions among brain areas are involved in a wide range of cognitive domains and correlate with performance, including cognitive control [16, 17], learning [18*], memory [19], attention [20], reward processing [21] and language [22]. Connectivity-based biofeedback studies have demonstrated that participants can be trained to self-regulate specific functional connections, resulting in desirable behavioral changes, such as increased subjective emotional valence ratings [23].…”