Journal of Neuroscience
October 31, 2012
Micah Allen, Martin Dietz, Karina S. Blair et al.
389 citations
A six-week randomized trial compared mindfulness training to an active control condition in healthy adults. Both groups improved on a response-inhibition task, but only the mindfulness group showed reduced emotional conflict on an affective Stroop task. The mindfulness group also showed greater dorsolateral prefrontal cortex activity during executive processing, suggesting increased use of top-down control. No overall group differences emerged for negative affect-related reaction times or brain responses. However, participants who practiced mindfulness the most showed improved response inhibition and greater recruitment of dorsal anterior cingulate cortex, medial prefrontal cortex, and right anterior insula during negative-valence processing. The findings indicate that mindfulness training engages distinct neural mechanisms at progressive stages and that optimal application may depend on context.
Synthese
January 1, 2018
Micah Allen, Karl J Friston
387 citations
Predictive processing (PP) approaches to the mind vary widely, from cognitivist views that rely on modular, internal mental representations to radical enactive and embodied theories. This review maps the continuum of PP theories, showing that some emphasize body-representations while others align with dynamic, enactive accounts. The Free Energy Principle (FEP) offers a formal framework that reconciles internalist and externalist perspectives by explaining how internal representations arise from autopoietic self-organization. The FEP thus provides a foundation for empirically productive process theories, such as PP, that guide research through formal modeling of the embodied mind.
Synthese
January 1, 2018
Shaun Gallagher, Micah Allen
221 citations
Three philosophical views on predictive models in neuroscience are distinguished: predictive coding, which relies on internal Bayesian models and prediction error minimization; predictive processing, linked to radical connectionism and simple embodiment; and predictive engagement, aligned with enactivist approaches to cognition. The concept of active inference is examined under each model, and its implications for social cognition are explored. The authors consider Frith and Friston's proposal for a neural hermeneutics and contrast it with an enactivist hermeneutics, offering an alternative account of how social understanding might work.
bioRxiv Preprint Server
April 10, 2019
Micah Allen, Andrew Levy, Thomas Parr et al.
100 citations
preprint
A formal model of cardiac active inference explains how signals from the heart influence perception of the outside world and confidence in that perception. Simulated experiments reproduce the defensive startle reflex and the link between the cardiac cycle and fear perception. Simulated interoceptive lesions reduce fear expectations, cause psychosomatic hallucinations, and worsen metacognitive biases. Synthetic heart-rate variability analyses show how the balance of arousal-priors and visceral prediction errors creates distinct patterns of physiological reactivity. The model provides a way to computationally characterize disordered brain-body interaction.
Frontiers in human neuroscience
January 1, 2013
Micah Allen, Jonathan Smallwood, Joanna Christensen et al.
100 citations
Mind-wandering, or task-unrelated thoughts (TUTs), is common and often impairs performance on demanding tasks, but new findings show it can also enhance metacognitive abilities. Using the Error Awareness Task (EAT), researchers found that individual differences in average TUTs strongly predicted stop accuracy, while variability in TUTs specifically predicted error awareness. Brain imaging revealed that both response inhibition and TUT ratings activated the medial prefrontal cortex (mPFC) of the default mode network (DMN), but in distinct dorsal areas, suggesting functional segregation. Co-activation of salience and default mode regions during error awareness linked monitoring to TUTs. The results suggest that fluctuations between internal and external thought, rather than constant focus, characterize individuals with greater metacognitive monitoring, and balancing these modes may optimize task performance.
Cerebral Cortex
June 10, 2021
Patricia Duerler, Silvia Brem, Gorka Fraga González et al.
64 citations
Psilocybin reduces brain responses to surprising tactile stimuli, altering the sense of body and self. In a combined EEG-fMRI study, psilocybin decreased activity in frontal regions, visual cortex, and cerebellum during unexpected touch, and reduced mismatch negativity signals at frontal electrodes. These changes were linked to altered body- and self-experience. The findings highlight the role of the 5-HT2A receptor system in processing unexpected bodily sensations and integrating them with self-awareness, which may inform treatments for psychiatric disorders involving distorted body perception.