Motivation and emotion/Book/2022/Interoception and emotion

Overview

 * Case study 1


 * Jessica has eaten her lunch and feels bloated and full. She knows that this means she is no longer hungry and stops eating. Jason has eaten three plates of spaghetti and is going for his fourth. He has undone his belt and is eating slower than when he started, but yet does not experience any intense "full" feeling. He continues to eat.

Everyone knows about the five senses humans have. These being sight, sound, taste, smell and touch. However, there are actually more than the commonly known five senses. In fact, there are eight senses that we possess. The other three being the vestibular system, proprioception and interoception. The vestibular system concerns the awareness of the body's position in space, proprioception informs us of the state of our muscle and joints (Fulkerson, 2014) and lastly, interoception is the awareness of our basic functions or needs (Ceunen, 2016). These basic functions and needs include things like feeling hungry or full, hot and cold, needing to go to the bathroom or being thirsty. Interoception's aim is to retain a homeostatic state in the body. Without it we could starve or overindulge. Freeze or dehydrate. Even accidentally voiding our bowels without realizing that we ever needed to go in the first place. But interoception is much more than its basic homeostatic functions, it is also involved in many areas of psychological research (Ceunen, 2016).

Focus questions
 * What is interoception?
 * What psychological theory helps us understand interoception development?
 * What is atypical interoception?
 * What is its relationship with emotion?
 * How do you improve interoception function?

What is interoception?


The first mentioning of the interoceptive concept was in the 1906 book "The Intergrative Action of the Nervous System" by Sherrington (Ceunen, 2016). Though the noun "interoception" would not be used until the 1940s, Sherrington did make use of similar terminology in his book, as well as creating the first definition for it (Ceunen, 2016). But what exactly is Interoception? Interoception is a broad internal sense which consensus on one definition is muddled. In general, it is defined as the perception of the state of the body (Ceunen, 2016). This definition can be interpreted through either a restrictive perspective, this being that interoception is only concerned with the sensations of internal organs located in the main cavity of the body, or it can be defined using the more popular inclusive perspective which views interoception as the sum of any phenomenological experience of the body (Ceunen, 2016). The functions and reach of interoception is not only concerned with retaining homeostasis in the body. Interoception is involved in many areas of study, including but not limited to: Autism (Shauder, 2016), emotion regulation (Price & Hooven, 2018), negative emotions (Pollatos et al., 2007), obesity (Herbert & Pollatos, 2014), anxiety and depression (Paulus & Stein, 2010), emotional experience (Wiens, 2005) and interoceptive conditioning (Pappens et al., 2013) among many, many other research areas and topics. Without expanding on each of the areas listed, the breadth of research areas that involve interoception goes to show the functions of interoception go deeper and spread farther than just simply retaining homeostasis (Ceunen, 2016).

What psychological theory helps us understand interoception development?


There is little understood about the development of interoception and the needs we attribute to the incoming interoceptive senses, like feeling full or feeling hungry. Although we feel these senses, how do we begin attributing needs to these senses? Well, there is a theory that aims to explain its origin using Bowlby's attachment theory (1982) as way of understanding how it is potentially developed overtime, beginning not long after birth (Oldroyd et al., 2019).

Attachment theory
Attachment theory, put forth by Bowlby (1982), is the theory of how caregivers and infants develop their emotional bonds. These bonds can determine how an infant will regulate emotions to how they experience close relationships later in life (Oldroyd et al., 2019). If a child feels safe and confident in their relationship with their caregiver, they are more likely to develop a secure attachment style to their caregiver. If the child's needs are being ignored or avoided, they may develop an avoidant attachment style. This can lead to the feeling of inability to rely on others later in life due to their caregivers only being conditionally available to their needs (Oldroyd et al., 2019). Children who believe that the parent is only available on the condition of meeting a certain standard, may develop an anxious style of attachment. This can lead to clinginess and becoming upset during separation from those they hold close relationships with (Oldroyd et al., 2019). The differences in attachment styles can be distinguished through how the hypothalamus-pituitary-adrenal-axis (HPA) activates with stress (Oldroyd et al., 2019) (Sheng et al., 2021). The HPA is a complex system that works to maintain a homeostatic state in the body, and the efficiency of the HPA's function may determine the ease with which the interoception signals are sent to the brain (Oldroyd et al., 2019). Since avoidant and anxious attachment styles are linked with dysregulation of the HPA reactivity to stress, which uses the same pathway as interoception, this theory posits that the attachment process is a potential determinant of interoception function due to its effect on the interoceptions pathway. Furthermore, this theory posits that since infants are unable to effectively communicate and understand their discomfort, they are unable to identify the discomfort until the parent attempts to alleviate it (Oldroyd et al., 2019). Poor or slow caregiving may lead to the infant misattributing or inaccurately identifying bodily sensations (Oldroyd et al., 2019).


 * Case study 2

The baby cries because she is in discomfort. She continues to cry until her caregiver places a bottle in its mouth, relieving the discomfort. She begins to attribute this discomfort to being hungry.

Relationship between interoception and emotion


In the modern era of emotion study, the realization that emotions are not solely just mental states and feelings that people experience but are also accompanied with a physiological response to each emotion is important for the discussion of interoception's relationship with emotion (Steimer, 2002). The debate of whether emotion causes the physiological changes, or that physiological arousal causes emotions, or a combination of both physiological arousal and cognitive appraisal resulting in emotions; has been a hot topic for many years. The arguments for each of these positions can be applied to the concept of interoception.

Schacter and Singer two-factor theory
The Schacter and Singer two factor theory views that the experience of physiological arousal as similar across the range of emotions and emphasizes that the cognitive appraisal given to the situation and signals is the most important aspect of the emotion felt (Schacter & Singer, 1962). Viewing the function of interoception through this lens, the function of interoception with emotion can be as follows: The internal signals of interoception are interpreted through the individuals affect, which determines their appraisal of the signal and therefore impacting their situation. For example, in anxiety and depression the expectance of negative body signals sets the individual up for body signal errors, meaning the difference in the current and anticipated body state, furthering their negative affect. This can make the individual more likely to avoid or withdraw (Paulus & Stein, 2010).

The James-Lange theory
The James-Lange theory posits that all emotions arise from physiological arousal (James, 1884). This can be exemplified through the reaction of fear, where the typical physiological reaction is an increased heart rate and blood pressure (Steimer, 2002). Viewing interoception through this theory, the physiological senses we experience through interoception influence our emotional responses and furthermore our behavioral responses. An example of this would be feeling of being heartbroken. The sense of a discomfort and pain in your heart causes you to feel the emotion of being heartbroken after the physiological arousal has been felt and identified (Dunn et al., 2010).

Case study 3 Ryan nearly got into a car crash and feels his heart racing and his palms sweating. He identifies these responses as fear and subsequently feels that emotion.

Lazarus' cognitive-mediational theory
Lazarus' cognitive-mediational theory posits that emotion and the physiological response that arises from it are all based on the appraisal that individual attributes to the stimulus (Lazarus & Folkman, 1984). A positive appraisal will typically elicit a positive appraisal and a negative appraisal will elicit a negative response. Applied to interoception, this can be seen as the physiological arousal, or interoceptive signal, coming as a result of the appraisal and subsequent emotion (Lazarus & Folkman, 1984). An example of this would be the emotion of stress. A stressful appraisal of a stimulus will lead to feeling the emotion of stress, leading to the interoceptive signals that are associated with stress (Schulz & Vogel, 2015).

Case study 4

Kyle is sitting an exam that is worth 20% of his grade. He has failed other assessments in this class and must pass this exam to pass the class and as a result he is very stressed about sitting the exam. His heart is racing, and he feels nauseous. Kimberley is also sitting this exam however she has performed well on all the other assessments and has already passed the class. Kimberley feels calm during this exam.

An important aspect of these three examples is the experience of the signal itself. The feeling of the interoceptive signal is otherwise known as interoception awareness (Garfinkel et al., 2015). Interoception awareness includes things like sensing your heartbeat, your stomach rumbling, the feeling of near bursting when you need to go the bathroom. The awareness of these is what makes up our feeling, however the accuracy of our awareness is not always correct. In some instances, we can even ignore, miss or treat our body's signals with mistrust (Herbert & Pollatos, 2014). Furthermore, the degree to which you feel these is your interoceptive sensitivity (Garfinkel et al., 2015). All three aspects are important to your overall interoceptive function. Poor function can stem from one or all three of these aspects and can lead to further effects on our emotions and wellbeing (Ceunen, 2016).

Obesity
Obesity being a prevalent issue in the western society has been linked with interoception dysregulation (Herbert & Pollatos, 2014). The aspect of interoception that has been linked with obesity is interoceptive sensitivity. Poor interoceptive sensitivity can potentially lead to being unable to discriminate between genuine hunger and being full (Herbert & Pollatos, 2014). Without the sensitivity of the "full" feeling being strong enough, obese individuals will continue to eat after reaching a satiated state leading to weight gain (Herbert & Pollatos, 2014). Obesity is also linked with depression, showing how poor interoception function can eventually lead to a condition which eventually affects the individual's emotional state (Blasco et al., 2020).

Depression
Along with major depressive disorder can come somatic body complaints and an irregular interoceptive awareness (Avery at al., 2013). Recent research has linked the insula cortical area of the brain with interoceptive awareness and discovered that individuals with major depressive disorder are receiving a large amount of interoceptive noise to this area (Avery et al., 2013). Interoceptive noise is the volume and strength of the signals that an individual is receiving. When there is too much interoceptive noise, discerning the origin and cause can be difficult (Avery et al., 2013). Interestingly, the insula cortical area of the brain is linked with emotion, further showing interceptions potential effects on emotion (Gogolla, 2017).

Improving interoception


Due to the plethora of conditions where irregular interoception function is involved, it is a logical step to seek ways on how to improve interoception function to alleviate any conditions impacted or caused by an irregular interoception. One of the best periods to incorporate interoception improvement strategies is in the classroom at a young age (Lean et al., 2019). Below are some strategies of improvement and the benefits that can accompany them. These strategies can be performed with an individual student, or with an entire classroom or school, and will usually last around 30 seconds in length (Lean et al., 2019). (Lean et al., 2019)

Benefits

 * Connecting to the body and emotions for better understanding
 * Gives us time to pay attention to what is going on in the body
 * Body awareness
 * Managing anxiety
 * Reducing stress
 * Promotes caring and empathy
 * Increasing prosocial behavior

(Lean et al., 2019)

Conclusion
Interoception is an integral part of the little-known fact that there are eight senses instead of the well-known five. Interoception is the eighth sense and, although definitions on this sense are broad and varied, it is generally defined as the awareness of the bodily senses (Ceunen, 2016). The wide range of research areas illustrates the amount that interoception can affect and influence various conditions (Ceunen, 2016).

There is little known about the development of interoception, however according to a theory proposed using Bowlby's attachment theory (1982) (Oldroyd et al., 2019), it can depend on what attachment style that is developed, whether it being secure, anxious or avoidant, its effects could impact the function of the HPA, a structure involved in interoception's function. This led to the idea that due to the HPA being impacted by attachment style, that it also impacts interoception function. It is also noteworthy that through attachment styles infants can attribute discomfort to certain needs (Oldroyd et al., 2019).

The relationship between interoception and emotion was looked at through the lens of three psychological theories, these being Shacter and Singer's two factor theory (Shacter & Singer, 1962), James-Lange's theory (James, 1884) and Lazarus' cognitive-mediational theory (Lazarus & Folkman, 1984). The Schachter and Singer two-factor theory combined physiological arousal and the cognitive appraisal of a situation, saying that the interoceptive signals are appraised depending on the individuals affect. The James-Lange theory posits that emotion is attributed to the physiological arousal felt by interoception, meaning emotion is felt after physiological arousal. Lazurus' cognitive-mediational theory holds the position that the cognitive appraisal of the stimulus is the most important aspect of determining the emotion, which when applied to interoception puts it last in the chain of events of an emotion. First is the stimulus, second is the appraisal, third is the emotion felt and last is the physiological response that arises from the combination of these (Lazarus & Folkman, 1984).

Interoception has also been linked with obesity and depression. In obesity interoceptive sensitivity is a potential culprit in the development of the condition. This was theorized to be due to the strength interoceptive sensitivity being weaker in obese individuals than in average weight individuals (Herbert & Pollatos, 2014). It is also noteworthy that obesity has a direct link with depression, showing how interoception function can indirectly effect emotion (Blasco et al., 2020). Interoceptions direct interaction with depression is through the insula cortical area of the brain, a brain area directly involved in emotion. Individuals with major depressive disorder experience a high volume of interoceptive noise, resulting in trouble discerning the origins of their interoceptive signals (Avery et al., 2013).

Interoception function is not concrete and can be improved at any time, however it is helpful to do so early on in life (Lean et al., 2019). This can be done through a few exercises that are usually about 30 seconds in length. Some exercises that improve interoceptive function are muscle activities, pulse activities and breathing activities. These activities typically involve performing an action twice, with the second time being asked to focus on awareness of a certain body part. The benefits of performing these actions include increasing body awareness, managing anxiety, reducing stress and increasing prosocial behavior among others listed (Lean et al., 2019).