How the Brain Becomes the Mind: Can Thermodynamics Explain the Emergence and Nature of Emotions?

Abstract

The neural systems' electric activities are fundamental for the phenomenology of consciousness. Sensory perception triggers an information/energy exchange with the environment, but the brain's recurrent activations maintain a resting state with constant parameters. Therefore, perception forms a closed thermodynamic cycle. In physics, the Carnot engine is an ideal thermodynamic cycle that converts heat from a hot reservoir into work, or inversely, requires work to transfer heat from a low- to a high-temperature reservoir (the reversed Carnot cycle). We analyze the high entropy brain by the endothermic reversed Carnot cycle. Its irreversible activations provide temporal directionality for future orientation. A flexible transfer between neural states inspires openness and creativity. In contrast, the low entropy resting state parallels reversible activations, which impose past focus via repetitive thinking, remorse, and regret. The exothermic Carnot cycle degrades mental energy. Therefore, the brain's energy/information balance formulates motivation, sensed as position or negative emotions. Our work provides an analytical perspective of positive and negative emotions and spontaneous behavior from the free energy principle. Furthermore, electrical activities, thoughts, and beliefs lend themselves to a temporal organization, an orthogonal condition to physical systems. Here, we suggest that an experimental validation of the thermodynamic origin of emotions might inspire better treatment options for mental diseases.

Keywords: Carnot cycle; brain state; consciousness; emotions; resting entropy.

Figure 1

The orthogonality of perception is a temporal organization. The chair behind the desk is a spatial organization, represented by brain frequencies and expressed by a temporal order of speech, thoughts, and actions.

Figure 2

The analysis of neural activation as a harmonic motion. The system returns to its starting position without creating memory (top). In a symbolic representation of the neuronal activation, red color represents a path between the brain’s modular structures (bottom). The vector path (A–B) is determined by the system’s memory and the stimulus’s qualities.

Figure 3

The cognitive burden of positive and negative emotions (drawn following [89]).

Figure 4

The characterization of emotions based on energy. The horizontal axis represents the mental abilities (mental energy), which change from an inability, such as apathy and depression, to confidence in mental action on the right. The vertical axis shows the environmental influence on arousal with a neutral state at the origin. Positive arousal generates surprise (top), and threat produces anxiety (bottom). A threat can trigger a fight or flight response.