Abstract
During value-based decision making, ventromedial prefrontal cortex (vmPFC) is thought to support choices by tracking the expected gain from different outcomes via a competition-based process. Using a computational neurostimulation approach we asked how perturbing this region might alter this competition and resulting value decisions. We simulated a perturbation of neural dynamics in a biophysically informed model of decision-making through in silico depolarization at the level of neuronal ensembles. Simulated depolarization increased baseline firing rates of pyramidal neurons, which altered their susceptibility to background noise, and thereby increased choice stochasticity. These behavioural predictions were compared to choice behaviour in healthy participants performing similar value decisions during transcranial direct current stimulation (tDCS), a non-invasive brain stimulation technique. We placed the soma depolarizing electrode over medial frontal PFC. In line with model predictions, this intervention resulted in more random choices. By contrast, no such effect was observed when placing the depolarizing electrode over lateral PFC. Using a causal manipulation of ventromedial and lateral prefrontal function, these results provide support for competition-based choice dynamics in human vmPFC, and introduce computational neurostimulation as a mechanistic assay for neurostimulation studies of cognition.
Highlights
Background inputD Current flow simulation Current flow simulation for medial stimulation for lateral stimulation for value-based choice, and could provide mechanistic rationales for interventions aimed at improving decision making in man.Here, we used a computational neurostimulation approach[22,23] to examine how perturbations of the assumed underlying attractor dynamics in ventromedial prefrontal cortex (vmPFC) might affect decision making behaviour
Perturbations in the biophysical attractor model (BAM) were realized through alteration of the membrane polarization[23,24], emulating the physiological changes elicited in humans through transcranial direct current stimulation
We simulated value-based decision making in a biophysical attractor model (BAM) known to describe features of cortical dynamics in decision making through interactions between populations of spiking neurons[12,13]
Summary
Background inputD Current flow simulation Current flow simulation for medial stimulation for lateral stimulation for value-based choice, and could provide mechanistic rationales for interventions aimed at improving decision making in man.Here, we used a computational neurostimulation approach[22,23] to examine how perturbations of the assumed underlying attractor dynamics in vmPFC might affect decision making behaviour. D Current flow simulation Current flow simulation for medial stimulation for lateral stimulation for value-based choice, and could provide mechanistic rationales for interventions aimed at improving decision making in man. In silico, how perturbing the competition between neural populations with neurostimulation affects value-based choice behaviour in a biophysical attractor model (BAM). Perturbations in the BAM were realized through alteration of the membrane polarization[23,24], emulating the physiological changes elicited in humans through transcranial direct current stimulation (tDCS). Behavioral predictions generated from this simulated neurostimulation intervention were compared to the behavioural consequences of an analogous experimental manipulation in human subjects performing a value-based decision making task. We elicited analogous large-scale membrane polarization changes by applying tDCS25,26 over medial frontal cortex
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
