The Readiness Potential reflects expectation, not uncertainty, in the timing of action

Abstract

Actions are guided by a combination of external cues, internal intentions and stored knowledge.Self-initiated voluntary actions, produced without any immediate external cue, may be preceded by a slow EEG Readiness Potential (RP) that progressively increases prior to action. The cognitive significance of this neural event is controversial. Some accounts link the RP to the fact that timing of voluntary actions is generated endogenously, without external constraints, and perhaps even randomly. Other accounts take the RP as reflecting the unique role of planning, therefore of temporal expectation, in voluntary actions. In many previous experiments, actions are both unconstrained by external cues, but also potentially involve preplanning and anticipation. To separate these factors, we developed a reinforcement learning paradigm where participants learned, through trial and error, the optimal time to act. If the RP reflects freedom from external constraint, its amplitude should be greater early in learning, when participants do not yet know the best time to act. Conversely, if the RP reflects planning, it should be greater later on, when participants have learned, and know in advance, the time of action. We found that RP amplitudes grew with learning, suggesting that this neural activity reflects planning and anticipation for the forthcoming action, rather than freedom from external constraint.Word Count: 6,346

Integrated World Modeling Theory (IWMT) Expanded: Implications for Theories of Consciousness and Artificial Intelligence

“…Theoretically, similar processes could be involved in generating particular actions, if visualization of acts is accompanied by a critical mass of model-evidence (as recurrent activity) accumulating in interoceptive/salience hierarchies (Rueter et al, 2018). Speculatively, this threshold crossing (or phase transition) may represent a source of readiness potentials (Park et al, 2020;Travers et al, 2020;Verleger et al, 2016), potentially understood as a kind of "ignition" event and driver of workspace dynamics (understood as high-level Bayesian model selection), corresponding to explosive percolation, triggered by the accumulation of recurrent-activity/model-evidence within upper levels of frontoparietal control hierarchies for enacting/inferring a particular (virtual or physical) proprioceptive state, or pose (Adams et al, 2013).…”

Integrated World Modeling Theory (IWMT) Implemented: Towards Reverse Engineering Consciousness with the Free Energy Principle and Active Inference

“…Theoretically, similar processes could be involved in generating particular actions, if visualization of acts is accompanied by a critical mass of model-evidence (as recurrent activity) accumulating in interoceptive/salience hierarchies [117]. Speculatively, this threshold crossing (or phase transition) may represent a source of readiness potentials [118][119][120], potentially understood as a kind of "ignition" event and driver of workspace dynamics (understood as high-level Bayesian model selection), corresponding to explosive percolation, triggered by the accumulation of recurrent-activity/model-evidence within upper levels of frontoparietal control hierarchies for enacting/inferring a particular (virtual or physical) proprioceptive state, or pose [121].…”