Consciousness as subjective experience emerges from the dynamics of the mental-simulation versus environment-coupling axis.

Abstract

Consciousness is primarily understood as a personal, subjective experience that can co-occur with various other subjective states, such as visual perception, emotions, memories, and awareness of actions. Many of these experiences are linked to the activation of well-defined neuronal processes, with their anatomical substrates often clearly identified. In this paper, we propose that consciousness emerges from dynamic changes in the activation of neuronal circuits responsible for monitoring and switching between large-scale mental simulations and those processes that couple our nervous system to the actual environment.We argue that the ability to anticipate the future is essential for survival; however, the utility of predictions is contingent upon their accuracy in modeling reality. We hypothesize that, as evolutionary pressures favored animals that could make increasingly accurate predictions, the same neuronal resources allocated for perception became shared with and engaged by mental simulations. Consequently, a new challenge arose for the nervous system: how to differentiate whether neuronal activity is serving externally generated stimuli or internally generated processes.We contend that consciousness evolved as a solution to the problem of signaling and flexibly transitioning between absorbing mental simulations and tightly coupling with the environment of complex living beings. This involves tracking the activation of multiple brain networks to determine whether an experience is real (originating from environmental interaction) or a mental simulation (autogenously generated). We propose that consciousness manifests as a subjective experience arising when fluctuations between mental simulations vs environmental coupling (MS/EC) occur. This mechanism aligns with the notion of a continuous and intensity-variable consciousness, where the intensity of conscious experience correlates with the magnitude of change along the MS/EC axis.We further discuss the implications of these ideas in relation to perception and dreaming, as well as their consequences for understanding certain neuropsychiatric disorders. Finally, we outline predictions and challenges posed by this theory, including potential anatomical substrates underlying the neuronal activity that gives rise to consciousness as a subjective experience.