The idea that all feelings are mental perceptions of homeostatic disequilibrium is a theory put forward by the psychologist and neuroscientist Lisa Feldman Barrett. According to her theory, known as the "Theory of Constructed Emotion," emotions are not pre-wired or fixed responses to specific stimuli but instead are constructed by the brain based on a combination of sensory inputs, past experiences, and cultural influences.
In this view, emotions arise as a result of the brain's attempt to make sense of bodily sensations and changes in response to internal and external events. These bodily sensations are closely related to the body's attempt to maintain balance or homeostasis. For instance, feelings of hunger or thirst might be considered perceptions of homeostatic disequilibrium because they signal a need to restore the body's balance by obtaining food or water.
According to Barrett's theory, the brain constantly predicts and constructs emotional experiences based on various sensory inputs and contextual information. Different patterns of bodily sensations and arousal are associated with various emotions, and the brain integrates these patterns to generate specific emotional experiences.
While Barrett's theory challenges traditional views of emotions as fixed and predetermined, it is not the only perspective on the subject. Emotions are a complex and multifaceted topic, and researchers continue to explore different theories and frameworks to understand their nature and origin fully. The study of emotions remains an active and evolving area of research in psychology and neuroscience.