The Relationship Between Allostasis and Emotion

Published on 02/20/23

Background Information:

The psychobiological process known as allostasis results in stability through state change as a result of stress. A perceived mismatch between one's perceived talents and the need of the environment is the definition of psychoemotional stress. The process of allostatic regulation denotes the maintenance and restoration of internal stability and viability amidst shifting conditions brought on by stress. It includes a variety of behavioral and physiological processes that control the homeostatic system's adaptive regulation in response to stress. Persistent hypertension, a flattened cortisol rhythm in serious depression, and chronic sleep deprivation are a few examples of allostatic conditions.

A systems neuroscience method to comprehend the nature of emotion is the theory of created emotion. It also provides a basic theoretical framework for guiding the development of hypotheses for how actions and experiences are created as a result of the brain's ongoing efforts to anticipate and satisfy metabolic demands (termed allostasis). Many symptoms of major depressive disorder (MDD), including fatigue, distress, context insensitivity, reward insensitivity, and motor retardation, are linked to persistent issues with energy regulation, supporting the hypothesis that allostatic dysregulation is a trans-disorder vulnerability for mental and physical illness.

Introduction:

What is the primary purpose of the brain? This question seems to have an obvious answer that most people will reach: 'to think.' However, neuroscientists claim that the brain's primary purpose is not to think but to do "body budgeting." In detail, the brain predicts and monitors the physical status to maintain needs under a constantly changing milieu based on internal and external aspects. In this context, the internal aspect represents an inner physical system such as metabolism, immune system, and autonomic nervous system, while the external aspect represents human surroundings. Neuroscientist Peter Sterling first introduced this mechanism called allostasis.

Given a similar name ending with -stasis, allostasis is often confused with homeostasis. Homeostasis is a passive error correction by feedback1, so the cycle's output is limited to internal balance recovery at a set point. The difference between the two mechanisms is clear: Homeostasis is the state of steady balance maintained by internal feedback, whereas allostasis is an active process of maintaining homeostasis based on a variety of information, including prior knowledge. Figure 1 shows this difference in the mechanism with a diagram.

Figure 1: Models to describe the mechanisms of homeostasis and allostasis

At this point, the emotion, or feeling, can be redefined with the concept of allostasis. Emotion indicates when the physical condition is out of the brain's prediction. It is a vital sign that notice the need for readjustment by delivering the request from each part of the body to the brain. Since the physical condition continuously changes so that the demand from each part of the body is always different, signs from emotion can make an infinite combination. This means it is impossible to experience the same feeling more than twice. However, the brain's limited capacity allows humans to experience similar feelings, making humans classify them as the same. It leads to the conclusion that "each behavior (fuming, crying, planning, withdrawing) is supported by a different physiological pattern in the body." 2

For example, human expresses anger in a fixed form, such as yelling, arguing, or throwing stuff. The expression will always be identical even though the cause and solution of it are numerous in variety. Since this response in fixed form ignores subtle differences and expresses uniformly, the brain has difficulty maintaining suitable balance, allostasis. Therefore, it is essential to recognize own emotions in a delicate and subdivided way, so one responds correctly to settle physical condition.

Our Illusion of Empathy and the Neuroscience Behind It:

Then, why is it so crucial to understanding this relationship? What real-life issue is related to it? The answer will be one of the most important social skills, empathy which is an ability to understand and share feelings with other people. Contrary to our common sense, the influential factors on empathy are not another's feelings but one's ability to recognize own emotion.

Research supports the claim with the result that empathy for pain involves the affective, not sensory components of pain (Singer et al., 2004). Participants were males and females in heterosexual monogamous relationships. They alternately got electric shocks on their fingers in the same room while recording the brain activity of the females. Figure 2 shows the result. Thalamus is a crucial area for pain perception, so it activates in the "self" condition that the participant directly feels physical pain. In addition, the researchers could identify the brain region active for both in the "self" condition and observing one's partner feeling pains which is the "other" condition. The insula region can communicate quickly with the brain regions responsible for homeostasis control functions such as heart rate.

Figure 2: Bilateral insula and mediodorsal thalamus The green colored area was activating in response to pain for the “self” condition whereas the red colored area for the “other” condition.

People have different levels of sensitivity to an internal sensory signal. The measurement of sensitivity is possible through Heart Rate Detection Task. As the perception of the heart rate is accurate, the level of sensitivity is high with high insula activity (Critchley & Harrison, 2013). In addition, high accuracy of heart rate perception can improve the ability to describe one's emotions accurately and carefully (Bornemann & Singer, 2017). To sum up, a strong argument can be made that all internal sensory signals going through the insula are significant in establishing and perceiving own emotion.

Individuals who develop their ability to recognize emotions with high sensitivity can also better understand others. They can read others' facial expressions more correctly (Grynberg & Pollatos, 2015) and better emphasize others' pain (Terasawa, Moriguchi, Takizawa & Umeda, 2014). Therefore, there is a clear correlation between high sensitivity and empathy. But, most people would not know their level of sensitivity. The implication here is that individuals might misunderstand they are emphasizing successfully with others, and this situation can cause serious conflict. In our society, where empathy can be found in various forms on social media, such as Like, emojis, comments, etc., one might mistake that it is easy to emphasize or force others to do so. Still, the neuroscience behind it demonstrates empathy requires a complicated mechanism.

Conclusion:

In conclusion, allostasis is the active process of sustaining homeostasis based on prior knowledge and prediction. When the brain fails to predict correctly, emotion is utilized as a sign of this failure. The behavior due to similar physiological patterns tends to be classified as one emotion, which might lower the accuracy of an ability to recognize own emotion. This might directly affect the process of empathy which is a self-centered ability. Individuals who can't perceive their feelings in detail might have difficulty effectively emphasizing with people. Thus, it is essential to subdivide and elaborate own emotions in order to recognize emotion more accurately.