Author: Trevor M. Day
Editors: Erin Vinson, Raayan Dhar
Abstract
Humans exhibit a high level of sociality and cooperation, which likely lead to the development of social rewards. In modern society, however, survival and physical safety are not of the utmost concern for the majority of people. Nevertheless, social rewards, and more broadly the reward system with reference to dopaminergic interactions remains persistent among modern day humans. Addiction can broadly encompass both addictive substances and addictive behaviors, as both are followed by large dopamine spikes upon their pursuit. When social rewards are either unavailable, or are perceived to be unavailable, the brain may attempt to substitute social rewards for specific addictive substances or behaviors. These substances and/or behaviours are inadequate substitutions for social rewards; they do not yield an oxytocin release and only take place in simple and unchanging environments. Conversely, natural social rewards yield oxytocin along with large amounts of dopamine. These rewards take place in complex and unique environments. With persistent yet inadequate substitutions of social rewards for addictive rewards, an addiction has a high probability of forming , especially due to the fact that levels of oxytocin will continue to not be met by an addictive reward, motivating additional substitutions. Thus, addiction is more likely to form if the individual has been exposed to an addictive reward prior to experiencing actual or perceived isolation.
How Isolation Fosters Addiction
In 2012 author Edward O. Wilson likened human beings to “eusocial apes”, in his book The Social Conquest of the Earth (Angier, 2012). Commonalities among eusocial animals in nature include cooperative care, especially care for children, overlapping generations functioning collectively, and division of reproduction (Hadley, 2020). However, this designation is highly debated in the scientific community, as evidence supporting the dissertation of eusociality is difficult to ethically gather. Perhaps humans display some signs of eusociality, but not others. What is not disputed, however, is that humans evolved to form social groups. With inferior physical attributes compared to ancient predators, our evolutionary ancestors banded together in small groups. According to Richard F. Taflinger at Washington State University, in what has become a popular sentiment amongst the greater evolutionary psychology community,
“Another aspect of personal survival is the forming of social groups within a species. When staying alive is not just the responsibility of the individual, but other members of the species help the individual to survive, and vice versa, all members' chances are enhanced” (Taflinger, 1996).
Luckily, one’s everyday life does not necessitate the understanding of the science behind sociality in humans. Instead, people naturally gravitate towards others, forming a variety of groups, friendships, acquaintances, and partnerships in several different contexts. Humans rely on one another traditionally for safety, but in the context of a relatively benign modern society, where physical safety is not often of concern, that function of human relationships seems to have been lost. When isolated, a person living today won’t face the same dangers early humans did many millennia ago. Unfortunately, evolution could have never prepared modern day humans for the immense challenge they face while isolated for extended periods of time: addiction.
Social interaction, like every other need and want humans demand, is a function of the reward system and circuitry in the brain. Krach, et al., in their 2010 literature review on reward systems and social interactions, writes “... there is evidence from a variety of studies that the dopaminergic reward circuits in the basal ganglia form the primary neural system for processing reward of various social stimuli which could motivate social behavior.” Crucially, the authors also highlight two other distinctions that also play a role in social rewards, namely other processes involving other neurotransmitters, such as oxytocin, and the complex situational circumstances that accompany social rewards. This distinction becomes extremely relevant when one begins to compare social rewards with rewards from addictive substances and behaviors.
The science of addiction has evolved considerably over the last decades. There are a variety of models of addiction that retain value for illustrating certain phenomena. This paper will specifically focus on the model of addiction that concerns itself with both addictive substances and addictive behaviors. Unfortunately, it is not immediately clear how physical withdrawal and dependence on chemical substances plays a role in addiction; these effects vary considerably based on the specific substance being abused. This, alongside the fact that there are many addictions, especially in the modern era, which cannot be adequately explained by the chemical dependency model (eg. internet addictions, pornography addictions, social media addictions). Clearly, the use of an alternative model to the standard chemical dependency model is necessary to highlight the effect isolation can have on a variety of addictions. Hence, in this paper addiction is used to describe both addictive substances and substance abuse, as well as addictive behaviors, with a focus on underlying commonalities between each type of addiction, specifically dopaminergic pathway reinforcement.
Current research among cognitive neuroscientists suggests that dopamine plays a crucial role in reinforcing addictions. Dopamine motivates individuals to find and seek rewards, including social rewards as discussed earlier by Krach et al. However, in an addiction, dopamine takes on another vital role. Namely, it serves to reinforce addictive behaviors and addictive substance abuse. Volkow et al. even surmise that the anticipation of pursuing a reward, not necessarily the attainment of the reward, is the mechanism by which dopamine plays a role in addiction (2011). In any case, large amounts of dopamine motivate individuals to compulsively seek out a certain reward, in the form of a substance or behavior.
Dopamine plays a key role both in motivating social rewards and strengthening addiction through either addictive behaviors or addictive substance abuse. Recall that social rewards also resulted in the release of oxycontin and that social rewards were situationally dependent (Krach, et al., 2010). When social rewards are unavailable or are even perceived to be unavailable, the other neurotransmitters, such as oxytocin, involved in social rewards are not released in sufficient quantities. One might perform or consume activities and/or substances that cause a large spike in dopamine. This should deliver the depleted neurotransmitters, because said activities are rewarding. This statement can be used to model the response in the brain from an evolutionary psychology perspective. In other words, when the brain notices that neurotransmitter levels associated with social rewards (a type of reward predicted by dopaminergic interactions) are depleted, the brain looks for a substitute (a different reward predicted by dopaminergic interactions). In prehistoric times, this would be a viable strategy, as virtually all activities or substances predicted by a large spike in dopamine upon there pursuit (ie. the activities are rewarding) also happened to be beneficial to the survival and development of the human. However, nowadays many of the substitutes for social reward, activities or substances that produce large dopamine spikes upon pursuit, are detrimental to the health of the human. Additionally, many addictive substances and behaviors provide a large spike in dopamine, but fail to provide many of the other neurotransmitters associated with social rewards (ie. oxytocin), with a notable exception being a short term spike of serotonin, which is responsible for the feeling of pleasure. Also, these addictive substances and behaviours do not take place in a complex environment, as do social rewards. In fact, many addictions are accompanied by a certain routine or ritual, all but eliminating the possibility of a complex and unique situation. Thus, isolation in the form of lack of social rewards or lack of perceived social rewards can cause addiction or further strengthen pre-existing addictions, because although addictive substances and/or behaviors are perceived as viable substitutes (as predicted by dopaminergic interactions) for social rewards, the addictive substances and/or behaviours do not provide adequate levels of other neurotransmitters, namely dopamine, nor do they take place in a complex environment, as do social rewards. It should be noted that isolation will cause or strengthen addiction with increased prevalence if the person who is isolated has also been exposed to the addictive substance or behavior before the isolation occurred and have adequate means to pursue the addictive substance or behavior. It is unlikely that an addiction could form without any previous exposure due to isolation, as social pressure plays a key role in establishing addictions. Ultimately, isolation can foster addiction more readily if the person has already been exposed to the addictive substance or behavior beforehand.
References
Angier, N. (2012). Edward O. Wilson’s new take on human nature. Smithsonian Magazine. https://www.smithsonianmag.com/science-nature/edward-o-wilsons-new-take-on-human-nature-160810520/
Hadley, D. (2020, February 19). What makes an insect social? ThoughtCo. https://www.thoughtco.com/what-are-social-insects-1968157
Krach, S., Paulus, F. M., Bodden, M., & Kircher, T. (2010). The rewarding nature of social interactions. Frontiers in Behavioural Neuroscience, 4, 22. https://doi.org/10.3389/fnbeh.2010.00022
Taflinger, R. F. (1996). Social basis of human behavior. Washington State University. https://public.wsu.edu/~taflinge/socself.html
Volkow, N. D., Wang, G., Fowler, J. S., Tomasi, D., & Telang, F. (2011). Addiction: Beyond dopamine reward circuitry. Proceedings of the National Academy of Sciences of the United States of America, 108(37), 15037-15042. https://doi.org/10.1073/pnas.1010654108
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