A habenula-insular circuit encodes the willingness to act

AbstractThe decision that it is worth doing something rather than nothing is a core yet understudied feature of voluntary behaviour. Here we study “willingness to act”, the probability of making a response given the context. Human volunteers encountered opportunities to make effortful actions in order to receive rewards, while watching a movie inside a 7 T MRI scanner. Reward and other context features determined willingness-to-act. Activity in the habenula tracked trial-by-trial variation in participants’ willingness-to-act. The anterior insula encoded individual environment features that determined this willingness. We identify a multi-layered network in which contextual information is encoded in the anterior insula, converges on the habenula, and is then transmitted to the supplementary motor area, where the decision is made to either act or refrain from acting via the nigrostriatal pathway.

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Resting State Functional Connectivity Predicts Future Changes in Sedentary Behavior

10.1101/2021.01.26.428161 ◽

2021 ◽

Author(s):

Timothy P. Morris ◽

Aaron Kucyi ◽

Sheeba Arnold Anteraper ◽

Maiya Rachel Geddes ◽

Alfonso Nieto-Castañon ◽

...

Keyword(s):

Functional Connectivity ◽

Resting State ◽

Exercise Intervention ◽

Supplementary Motor Area ◽

Anterior Insula ◽

Motor Area ◽

Anterior Cingulate ◽

Sedentary Behaviors ◽

Resting State Functional Connectivity ◽

The Right

AbstractInformation about a person’s available energy resources is integrated in daily behavioral choices that weigh motor costs against expected rewards. It has been posited that humans have an innate attraction towards effort minimization and that executive control is required to overcome this prepotent disposition. With sedentary behaviors increasing at the cost of millions of dollars spent in health care and productivity losses due to physical inactivity-related deaths, understanding the predictors of sedentary behaviors will improve future intervention development and precision medicine approaches. In 64 healthy older adults participating in a 6-month aerobic exercise intervention, we use neuroimaging (resting state functional connectivity), baseline measures of executive function and accelerometer measures of time spent sedentary to predict future changes in objectively measured time spent sedentary in daily life. Using cross-validation and bootstrap resampling, our results demonstrate that functional connectivity between 1) the anterior cingulate cortex and the supplementary motor area and 2) the right anterior insula and the left temporoparietal/temporooccipital junction, predict changes in time spent sedentary, whereas baseline cognitive, behavioral and demographic measures do not. Previous research has shown activation in and between the anterior cingulate and supplementary motor area as well as in the right anterior insula during effort avoidance and tasks that integrate motor costs and reward benefits in effort-based decision making. Our results add important knowledge toward understanding mechanistic associations underlying complex sedentary behaviors.

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Insula cortex gates the interplay of action observation and preparation for controlled imitation

10.1101/2020.11.05.370718 ◽

2020 ◽

Author(s):

Megan E. J. Campbell ◽

Vinh T. Nguyen ◽

Ross Cunnington ◽

Michael Breakspear

Keyword(s):

Supplementary Motor Area ◽

Action Observation ◽

Computational Modelling ◽

Motor Planning ◽

Action Planning ◽

Brain Network ◽

Anterior Insula ◽

Motor Area ◽

Early Motion ◽

Insula Cortex

AbstractPerceiving, anticipating and responding to the actions of another person are fundamentally entwined processes such that seeing another’s movement can prompt automatic imitation, as in social mimicry and contagious yawning. Yet the direct-matching of others’ movements is not always appropriate, so this tendency must be controlled. This necessitates the hierarchical integration of the systems for action mirroring with domain-general control networks. Here we use functional magnetic resonance imaging (fMRI) and computational modelling to examine the top-down and context-dependent modulation of mirror representations and their influence on motor planning. Participants performed actions that either intentionally or incidentally imitated, or counter-imitated, an observed action. Analyses of these fMRI data revealed a region in the mid-occipital gyrus (MOG) where activity differed between imitation versus counter-imitation in a manner that depended on whether this was intentional or incidental. To identify broader cortical network mechanisms underlying this interaction between intention and imitativeness, we used dynamic causal modelling to pose specific hypotheses which embody assumptions about inter-areal interactions and contextual modulations. These models each incorporated four regions - medial temporal V5 (early motion perception), MOG (action-observation), supplementary motor area (action planning), and anterior insula (executive control) – but differ in their interactions and hierarchical structure. The best model of our data afforded a crucial role for the anterior insula, gating the interaction of supplementary motor area and MOG activity. This provides a novel brain network-based account of task-dependent control over the integration of motor planning and mirror systems, with mirror responses suppressed for intentional counter-imitation.

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