Homeostatic feeling

Homeostatic feeling is a class of feelings (e.g. thirst, fatigue, pain, desire, malaise, well-being) that inform us about our physiological condition. In his earlier work Antonio Damasio used "primordial feeling" but he now prefers the term "homeostatic feeling" for the class.

Affective neuroscientist, Jaak Panksepp, identified homeostatic feeling as one of three primary classes of affect:
 * homeostatic affect: e.g., thirst, fatigue
 * sensory affect: e.g., touch, warmth
 * emotional affect: e.g., anger, fear.

Some homeostatic feelings motivate specific behavior aimed at maintaining the body in its ideal state. For example, hunger motivates eating, fatigue motivates resting and hyperthermia motivates stepping into the shade. Neuroscientist Derek Denton called these motivating homeostatic feelings "primordial emotions" and defined them as "the subjective element of the instincts, which are the genetically programmed behaviour patterns which contrive homeostasis. They include thirst, hunger for air, hunger for food, pain, hunger for specific minerals etc. There are two constituents of a primordial emotionthe specific sensation which when severe may be imperious, and the compelling intention for gratification by a consummatory act."

Neuroanatomist Arthur Craig called these motivating homeostatic feelings "homeostatic emotions" and found that humans and anthropoid primates form an image of all of the body's unique homeostatic sensations in the brain's primary interoceptive cortex (located in the dorsal posterior insula). This image is re-represented in the mid- and anterior insula, and the anterior insula (modified by input from cognitive, affective and reward-related circuits) plays a role in conscious awareness of the whole body's homeostatic state. A sensation re-represented in the anterior insula and that sensation's related motivation (involving neural activity in the anterior cingulate cortex and other regions) form a homeostatic emotion.

Consciousness
Derek Denton proposed that primordial emotions are the likely incubators of consciousness in evolution; that a kind of non-reflective consciousness evolved along with these feelings and before the emergence of cognition. This opposes the view put by Edelman and others that consciousness emerged after the development of cognitive processes such as the ability to create a scene from diverse sensory inputs.

Denton saw the evolution of consciousness as a gradual, continuous process, beginning in the brain's most primitive regions with non-reflective consciousness of instincts, followed by the emergence of reflective consciousness of the sensations and impulses that comprise these instincts, then reflective consciousness of surroundings evolves, followed by the emergence of reflective consciousness of memories and behavioural options.

Antonio and Hanna Damasio, too, observe, "It is likely that homeostatic feelings were the inaugural phenomena of consciousness in evolution ..." and propose that "homeostatic feelings were selected [by evolution] because the spontaneous information they provided regarding the current state of life regulation conferred extraordinary advantages to the respective organisms. The ‘knowledge’ carried by conscious homeostatic feelings enabled overt guidance of life regulation."

Antonio Damasio in his 2021 book, "Feeling and Knowing", argues that without ongoing awareness of our homeostatic state, no other mode of consciousness (such as awareness of surroundings, memories and self) is possible.