by Ruqaiya Mithani
art by Caitlin O’Neil
“Now that I look back, we were so toxic, it obviously wasn’t healthy anymore.”
“They’re so toxic together, I don’t know how they don’t realize.”
“The last time you guys got back together, it ended the same way. It’s so toxic, don’t you see?”
With the rise of buzzwords like “red flag” and “gaslight” making an appearance in nearly every tweet, post, and internet video, the term “toxic relationship” and the circumstances surrounding them have become a hot topic in daily conversation. While awareness and methods of identifying toxic relationships have exponentially increased, how exactly healthy relationships turn into a negative dependence between partners remains largely unexplored. Toxic relationships do not occur solely due to social factors, but may also have a neurological basis—eventually creating relationships just as difficult to leave as they are to be a part of.
The “Toxic” in Toxic Relationships
Before taking a turn for the worse, many relationships are formed and maintained in a healthy manner. Healthy relationships are based on mutual feelings of care, respect, investment in a partner’s happiness, and shared control and input when making decisions . Toxic relationships, on the other hand, look nothing like this. A “toxic relationship” can take many forms—from platonic and familial relationships to romantic relationships—and they all have their own standards for toxicity. Dr. Lillian Glass has introduced one of the earliest and most comprehensive definitions of what makes a relationship “toxic.” In her book Toxic People, Dr. Glass defines toxic relationships as “any relationship [between people who] do not support each other, where there’s conflict and one seeks to undermine the other, where there’s competition, where there’s disrespect and a lack of cohesiveness” . In terms of romantic relationships, the definition was later expanded to include a few more key themes. One of them being “relationship disparity,” or a situation in which one partner is dependent on the other to facilitate the dominance and subjection of one partner over another, emotional dependence, and exploitation . Between partners, this could look like deferring to one person to make all the decisions in the relationship, even highly personal ones, like what to eat for lunch, or what one can and cannot wear. This domination may begin slowly with smaller attempts to control another, but can quickly snowball into a toxic dynamic.
In broader terms, toxicity in romantic relationships often appears when one partner depends on another for nurturance, protection, and support in situations where they have the ability to function on their own . The dependency that is sometimes present in toxic relationships has been connected to the behaviors seen in people with dependent personality disorder. Although not all persons in toxic relationships that experience this dependence have mental illnesses, the strategies that dependent people with this disorder exhibit may also be present in partners within toxic relationships that are dependent on their significant other. Some key strategies that are seen in partner dependency include supplication, where the dependee portrays themself as helpless and vulnerable in order to convince their dependent to remain in their relationship, and ingratiation, boosting their partner’s ego or making their partner feel indebted to them, securing their dependency . In these situations, the dependent can take advantage of the dependee’s attachment and exploit them to gain control and feel admired . At the same time, the dependee can be seen partaking in self-sabotaging behavior, trying to “cancel themselves out,” making their opinions and voice in the relationships as small and submissive as possible to facilitate their dependence .
All in all, toxic relationships are characterized by a mixture of unequal power dynamics and miscommunication, unintentionally insulting words and actions—often in varying amounts—and ultimately leaving one or more individuals feeling insignificant . While toxic relationships involve unhealthy habits and interactions, they can quickly escalate to levels of abuse and include a deliberate form of harm and control . The line between the two, however, is blurry. In the context of romantic relationships, abuse can include a range of physical, sexual, and psychological maltreatment used by one person against the other in an intimate relationship to gain or maintain authority . While abusive relationships can be categorized as toxic, toxic relationships usually do not include deliberate forms of abuse. Instead, they result from unhealthy habits that turn into cyclic behavior . This cycle includes the following phases: the tension-building phase, the explosive phase, the honeymoon phase, and the calm phase . During tension-building, relationships begin to become uneasy, with partners having trouble communicating, getting frequently annoyed with each other, or shifting from equal power to one partner gaining power over the other . This can be followed by some kind of incident, such as a big argument (acting out phase) explosive phase . The following phase, appropriately deemed the honeymoon phase, is when some type of reconciliation occurs, including apologies or promises for the future, usually done by the domineering partner  The end of the cycle comes with the calm phase, where it seems there was no issue to begin with and the couple moves forward, often with the domineering partner buying their significant other gifts and acting like they have changed () This cycle is also seen in abusive relationships, where the incident is exacerbated by physical or emotional abuse. The two types of relationships show significant overlap in behaviors exhibited, and an intention of harming the other is what usually distinguishes the two . Understanding how toxic relationships develop on a neurological level can help us prevent the transition of a relationship from toxic to abusive and reduce the damage that follows.
Head Over Heels? The Neurology Behind Toxic Relationships
Toxic relationships arise out of our conditioned definition of what healthy love looks and feels like. How can love be inspiring and supportive one minute, and invalidating and controlling the next? The answer to this question may be found in the neurological similarities between love and addiction . Within the brain, neurons and their axons project and convey information to specific brain structures in a specific manner through brain pathways. The pathway that signals the brain that a rewarding or pleasurable stimulus is being presented in response to an action is called the reward-signaling pathway . This pathway is activated when the reward is present and motivates us to remember and repeat this beneficial behavior to trigger some kind of reward. Substance addiction and love involve the same reward-signaling, conditioning, and reinforcement pathways, generating the comparison between the two phenomena , . For example, when first using a drug, there is often a euphoric or pleasurable feeling that follows. The reward of using this drug is that “good feeling,” tempting you to use it again. Upon repetitive use, your brain reinforces this behavior, making you want to use the drug more to gain the reward, resulting in addiction being created. Similarly in love, being with a partner also creates feelings of happiness and joy. Their voice, smile, and simply their presence also elicit that “good feeling,” and over time your brain will associate spending time with them with the reward of these positive emotions. While the creation of this desire is often called love, it follows the same trajectory as addiction.
Another similarity between love and addiction is the release and proliferation of dopamine, a neurotransmitter commonly associated with reward and pleasure, in a brain region called the nucleus accumbens The nucleus accumbens is part of the brain’s basal ganglia, a region deep within the brain with many functions, notably motor learning, executive functions and behaviors, and emotions . The nucleus accumbens specifically, is involved in mediating reward and satisfaction, as well as motivation and incentive . Addiction activates the mesolimbic dopamine pathway, more commonly known as the reward pathway . Within this pathway, the release of dopamine in the nucleus accumbens is known to control drug reward and cravings in humans while the activation of the other structures in the pathway are responsible for motivation and how saliently, or how strongly, we perceive reward-related cues . In love, the same dopaminergic, or dopamine-producing and releasing, pathway is activated. In studies conducted with prairie voles, rodents that are
common animal models for love studies due to their monogamous nature, the release of dopamine in the nucleus accumbens and the activation of the mesolimbic dopamine pathway occurs when these mammals form pair bonds . Pair bonding in these animals is similar to the formation of partner relationships and attachments in humans. Dopamine released from the nucleus accumbens is vital in inducing pair bonds in prairie vole mating partners, along with the nonspecific activation of dopamine receptors in the nucleus accumbens [15, 16].Just as dopamine is important in forming an addiction to drugs, it is just as important in pair bonding activities and by proxy, in love .
In addition to the overlapping dopaminergic pathways in both love and addiction, there are two other neurochemical systems within the brain that these two phenomena share. The first of these is the endogenous opiate system, a system that regulates reinforcement of rewards including food, water, and sex . This system has three opiate receptors: MOR and DOR, associated with positive motivation and affect, and KOR, associated with negative motivation and aversion or avoidance . With addiction, MOR is activated in the nucleus accumbens and other brain regions, such as the ventral pallidum and ventral tegmental area. The ventral tegmental area specifically, an area associated with learning, memory, addiction and reward , is also implicated in love, with those in love showing greater activity in this region, and in its MOR receptors over time . This activation of MOR is key to establishing and maintaining the positive motivation and reinforcement of drug abuse in humans, as well as in love. KOR was found to work similarly in maintaining drug abuse and pair bonding relations in both addiction and love . The second neurochemical system that has been implicated in love and addiction revolves around corticotropin-releasing hormone (CRF). CRF is produced and released as part of withdrawal, primarily creating a chronic stress response that places an individual in a state of worry and increases cravings, tempting a relapse in both drug use and in love. [20, 21]. Another study using prairie voles suggests that the CRF system controls reactions to social loss and depression, and that both loss of love and addiction hijack this pathway to trigger withdrawal symptoms .
While the similarities between toxic relationships and addiction can explain why it is so difficult to leave a toxic relationship, healthy love can also be seen as a type of addiction.
Many of the stages associated with new love include spending lots of time with a new partner, missing their presence, and feeling “butterflies” while thinking of or spending time with them . In love, these experiences sound romantic. But their connotation changes drastically when described in association with addiction. In the context of addition, these actions can be reworded so that missing someone intensely correlates with craving in substance abuse, “butterflies” become the euphoric and intoxicating feelings that substances create, and constantly being with them connects to building a tolerance and dependency to a substance) . With even healthy love being a slippery slope when it comes to comparisons with addiction, the similarities between toxic love and addiction serve as their own red flags, warning us of how dangerous toxic relationships can really be.
Accountable Attachment: How Childhood Relationships Can Influence Toxic Relationships
Vulnerability to entering one or multiple toxic relationships may not be completely random. According to the attachment theory, a theory first formulated by psychologist John Bowlby in 1988, attachment is innate and has evolved to enhance infant survival, but doesn’t stop in early age . An individual’s attachment type continues to influence how they craft relationships across the span of their life [23, 24]. Later expanded on notably by psychologist Mary Ainsworth and several other scientists, attachment theory suggests that there are four distinct attachment styles: secure, anxious, avoidant, and disorganized, with the latter three falling under the umbrella of insecure attachment types. Secure attachment is defined as the ability to form healthy and long-lasting relationships and mostly comes from a childhood where an individual could consistently rely on their parental figures or caregivers to provide a safe and open relationship . Insecure attachments, however, usually stem from a strained relationship with caregivers early in life, resulting in the different types mentioned previously.
The avoidant attachment style is often observed in individuals who were rejected, ignored, or ridiculed when they needed comfort as children, resulting in over-independence and trouble trusting partners in relationships during adulthood . The anxious attachment type is often observed in individuals whose childhood caregivers showed inconsistent care, making the child prioritize the parent’s overwhelming feelings over their own . Those who develop anxious attachment often need constant reassurance, develop low self-esteem, and blame themselves for the lows of their relationships. The disorganized attachment style is slightly more nuanced, as individuals who display disorganized attachment often suffer from abuse or caregivers with their own unresolved trauma, causing mixed behaviors . Individuals with a disorganized attachment style often have inconsistent and unpredictable responses in relationships, flipping back and forth between clingy or emotional behavior, and distant or independent behavior . These insecure attachment styles are seen more commonly in toxic relationships than in healthy ones .
Although these attachment styles will not always result in toxic relationships, studies show that the combination of avoidant and anxious attachment styles is highly observed in couples experiencing domestic violence and abuse . Male-female couples where the female had an anxious style and the male had an avoidant style were recognized as particularly toxic. A couple with this combination of attachment styles is nine times as likely to experience partner violence and abuse than couples with other attachment style combinations . Other research surrounding anxious attachment styles, also known as preoccupied attachment style, suggests that although these individuals want to develop stable and secure relationships, the anxiety they have about how insecure their relationship is, prevents them from building a trusting, committed relationship with anyone Individuals that are characterized as avoidant and anxious reported experiencing less trust and satisfaction in their relationships when compared to those that were characterized as having a secure attachment style, as well as reported overall more negative emotions and less positive emotions in their relationships . The largely insecure attachment styles alone and especially in combination often lead to relationships that lead to toxicity and in extreme cases, abuse.
All this current research on the possible neuroscience behind the formation of toxic relationships and their cyclic nature begs the question: how can one leave a toxic relationship for good? The answer to this question is still being explored within the field today. While emerging research has yet to provide scientifically supported remedies for toxic relationships, therapists, counselors, and relationship coaches are weighing in on actions to be taken to escape a toxic relationship. In an article for The Insider, licensed professional therapist specializing in couples counseling Jayne Green, advises planning out the exit, as this inspires confidence and helps work out any logistical challenges that may tempt one to return to the relationship . Oftentimes what pulls people back into toxic relationships, is the “good”—human beings have a tendency to focus on the happy, joyful memories of a relationship and ignore the manipulative and unhealthy aspects that made the relationship toxic in the first place . This behavior is synonymous with focusing on the reward the relationship results in while overlooking the pain in the process. Physician and clinical mental health writer Kristen Fuller recommends reaching out to your support system. Having supportive family, friends, and trusted people in your corner makes the process of leaving that much easier. These people provide comfort that one would have received from their toxic partner while also encouraging them to maintain their resolve in stepping away from that toxic partner [29, 31]. Both Green and Fuller, along with a handful of other professionals, emphasize expressing your emotions, and if you are able, directly to the toxic ex-partner. When ending a toxic relationship, writing down your emotions using “I” statements and communicating them to the other allows not only for a clean and distinct end, but also provides a space to move forward [29, 31]. Talking through the emotions after the breakup, such as still longing for your previous partner, or wanting to get back together, with professionals or your support system, can provide further emotional clarity. The conversations may be emotional and difficult to get through, but having them can help break the toxic cycles and disrupt the associations of reward that the toxic relationship had previously created [9, 29].
Toxic relationships are exactly as they sound: toxic. What starts as troubles in a romantic relationship can spread and corrupt other parts of your life. Their correlation to neural mechanisms in the brain makes them more dangerous and stronger than they seem on the surface. Recognizing how toxic relationships can go beyond what they look like on social media and subsequently increasing awareness, can help us promote healthy relationships as a community. By educating ourselves and gaining knowledge on the inner workings of toxic relationships, we can take proactive steps to intercept negative patterns of behavior before they become more serious, affecting not only our social lives, but how our brains are wired as well. Awareness can help us form and maintain healthy and positive relationships, and prevent toxic situations from escalating into abusive or harmful behaviors.
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