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Bonds Beyond Borders

by Victoria Esquibies art by Mina Kamara

The scope of the immigration crisis at the southern border is regularly considered through a collective lens, often diminishing the experience of the individual throughout migration. By analyzing a traumatic migration experience and the resulting psychological and neurological effects through the personal story of an individual, the extent of this crisis can be better understood. David is a minor of Indigenous Maya descent whose family fled Guatemala to escape civil war in 1960 [1]. His parents, Evelyn and Carlos, sought to make a living in Mexico, but instead settled in Alabama without legal status due to a lack of employment offers. Evelyn gave birth to David in 2003, making him a U.S. citizen—a status significantly different from most immigrant children who face hardships at the southern border. David’s legal documentation, however, did not spare him from experiencing the injustice of the U.S. immigration system [1].

Recently, the United States Border Patrol reported that they had apprehended 400,651 migrants at the southwest border between October 2019 and September 2020. This count included 30,557 unaccompanied minors [2]. During this time, the Department of Justice under the Trump administration implemented a “zero-tolerance” policy to punish those caught entering the US illegally. This policy meant that unauthorized immigrants traveling with minors would be criminally prosecuted and separated from their familial units [3]. Within this framework, numerous immigrant families continue to experience disruption in the attachment process between parent and child.

Attachment Theory & Separation According to the attachment theory developed by psychiatrist John Bowlby, young children need to develop a relationship with at least one primary caregiver for normal social and emotional development [4]. However, caregivers must remain consistently available for children to become attached to them. For infants and children, this refers to maintaining physical accessibility until a threatening stimulus or situation has passed [4]. If parents are physically removed from their children, as was the case at the southern border during the zero-tolerance policy, these important relationships cannot be fostered.

David was one such migrant child unjustly separated from his family as a result of the family separation policy [1]. At the age of four, David and his mother returned to Mexico, with Carlos joining two years later. In 2017, financial issues and a desire for a better education prompted David and his father to return to the United States. When they arrived at the border, federal immigration applied the zero-tolerance policy. The two were separated and 14-year-old David was placed under provisional care with the Department of Child Services in Arizona [1].

In this scenario, rather than allow immigrant families to remain united throughout the migration process, the U.S. government separated thousands of immigrant children from their guardians. This separation disrupts the child-caregiver attachment crucial for child development [1]. An early study by American psychologists Harlow and Zimmerman identified the root of this child-caregiver relationship and provided the foundations for the concept of attachment theory [5]. In the experiment, infant monkeys were separated from their mothers and placed in cages with “surrogate mothers.” This finding suggests that the goal of attachment is not the fulfillment of needs, but rather an intrinsic need for an emotional and physical bond with a caregiver [5]. As a result of the zero-tolerance policy, children like David have been neglected the opportunity to create the emotional and physical attachment that is innately characteristic of living beings.

In his attachment theory, Bowlby emphasized critical periods during the development of the infant-parent attachment relationship [4]. He stated that strong emotional attachments develop primarily over the first years of a child’s life, particularly from six months to 24 months of age [6]. This critical period is when neural networks in the brain can most easily change through growth and reorganization, an ability known as neuroplasticity [7]. This coincides with the ages that many children were separated from their parents as a result of the zero-tolerance policy, with at least 100 of the thousands of separated children being under the age of five [3]. David, although 14 when he experienced guardian separation, still experienced extreme psychological harm, suggesting that separation for those children within the critical period may be even harsher.

Neuroanatomical Alterations Due to Traumatic Migration The consequences of attachment disruption during a child’s critical period appear to not only affect their future psychological state, but also the structure and function of their brains. The amygdala, which is the core neural structure for processing fearful and threatening stimuli, is thought to change in response to attachment disruption [8]. Its functions include the detection of threat and the activation of appropriate fear-related behaviors in response to threatening stimuli, also known as emotion regulation [8]. It has been found that adversity early in life, specifically insufficient caregiving, can negatively affect children’s amygdala functioning [9]. This finding suggests that children like David may experience significant issues with emotional processing. That is, they may perceive situations to be more threatening than they actually are, or may misinterpret threatening stimuli, possibly leading to dangerous outcomes that put themselves or others at risk.

Amygdala alteration due to child-caregiver separation has been analyzed through several research studies [10, 11, 12]. In a recent study, 38 children aged five to eleven who previously lived in orphanages were assessed [10]. An orphanage is an early life environment with a high child-to-caregiver ratio, similar to the absence of a child-guardian attachment in immigration detainment centers. This similarity suggests that studies conducted in orphanages may have valuable implications for understanding the neuroscience behind family separation-induced trauma in the context of immigration. Using neuroimaging tools, researchers found that orphaned children had increased amygdala size. This finding suggests that amygdala anatomy could physically change as a result of child-caregiver disruption, meaning that the thousands of children separated at the southern border may be susceptible to worsened emotional processing [10]. Additionally, this stress-related amygdala growth appears to be resistant to recovery in comparison to other brain structures, like the memory-related hippocampus. This indicates that early-life stress can have long-term, irreversible effects on the fear-processing organ of its victims [10].

Unfortunately, change in amygdala size and function is not the only developmental disruption migrant children may experience due to family separation.

The long-term effects of early life stress suggest that children who have experienced familial separation may face hardships as they navigate new environments and relationships. Such functional and structural brain changes in humans that have experienced early life stressors (ELS) demonstrate that the U.S. government’s immigration laws have tangible health consequences. In a study conducted by Puetz and colleagues, the brain activity of 25 foster or adopted children with ELS was compared with that of 26 non-separated children [13]. Instead of studying amygdala size, researchers focused on neural activation during a social rejection simulation [13].

Peer rejection is classified as one of the most distressing social experiences for both adolescents and adults. Previous studies have shown that adults, adolescents, and children who have experienced ELS are at the highest risk of being rejected by their peers [14, 15, 16]. Factors such as parental support, maternal comfort, and proper attachment strengthen emotion regulation skills, classifying them as “protective factors” that can aid in coping with social rejection and hardship [18]. Children with ELS, such as immigrant children who have undergone family separation, lack these protective factors, which may affect neural structures underlying the ability to regulate the distress of exclusion [13]. These structures include the prefrontal cortex (PFC) and the dorsal anterior cingulate cortex (dACC), which play a central role in cognitive control functions including attention, impulse inhibition, prospective memory, and cognitive flexibility (Prefrontal cortex 2020).

Puetz et al. (2014) focused on these two brain structures when analyzing neuroimaging data after the subjects experienced a social rejection paradigm [13]. This paradigm led the children to believe that they were joining peers for a ball-tossing game via the Internet, though they actually played against the computer. It had three distinct conditions: exclusion due to technical difficulties, inclusion in the game, and social exclusion from the game. While experiencing peer rejection, children with ELS exhibited significantly reduced neural activation in the dACC and dorsolateral PFC (dlPFC) compared to control children. Researchers reported reduced connectivity between the dlPFC and dACC, meaning that the circuit relationship between the two structures that normally aid in emotion regulation was negatively affected [13]. The data suggests that dysfunctional neural processing of social rejection occurs in children with ELS and that it may manifest as enhanced feelings of frustration and exclusion in a social rejection setting. Furthermore, these studies suggest that the effects of early adversity on the developing brain are long-lasting. Children who have encountered a traumatic migration experience at the southern border are therefore vulnerable to neuroanatomical changes between different brain structures; their adversity in early life will likely have residual effects on how they process and respond to socially distressing situations.

Children’s brains have shown remarkable levels of neuroplasticity [19]. In situations of prolonged hardship like migration, the adolescent brain will adapt to a level of functioning that seeks to preserve life out of fear. Children may develop complex patterns of protective responses that can include hyperarousal—hypervigilance, agitation, flashbacks, and emotional reactivity—dissociative responses, emotional numbing, passive compliance, and poor cognitive functioning [19]. These protective responses may actually do more harm than good in the long term, leaving children susceptible to the development of maladaptive disorders and behaviors.

Environmental and Psychological Factors of Traumatic Migration Although the protective responses migrant children experience may directly result from family separation, they may also stem from the inhumane environment they endure in detention centers. As previously mentioned, detention centers—like orphanages—offer a low caregiver-to-child ratio. Hygiene and health are oftentimes neglected in these environments, with reports showing that many children frequently continue to wear the same clothes from when they crossed the border [4]. Access to soap, toothbrushes, and showers is limited, proving that the environment is detrimental to the health of any adult, let alone a child [4]. In an interview, David described his time at a community detention center after he was separated from his parents, stating that he had trouble eating and sleeping due to his environment [1]. Environmental conditions hold significant weight in the development of psychological disorders and maladaptive psychiatric symptomatology. After his detainment, David struggled to explain his feelings until he was later able to associate his somatic symptoms to what he identified as “depression” [1]. David’s testimony only verifies that without a safe, stable environment, a child may struggle to thrive.

A study of psychiatric symptoms in teenage and adult asylum seekers in detention centers found that asylum seekers reported clinically significant levels of anxiety, depression, and post-traumatic stress disorder (PTSD) [20]. These disorders manifest through a variety of different symptoms. For David, this included a loss of appetite and the increased difficulty sleeping mentioned previously [1]. These symptoms also indicate that David was dealing with toxic stress—prolonged exposure to stressful experiences—that can permanently alter brain chemistry [1]. If children are required to live in an inhumane environment that neglects health and hygiene for long periods of time, it is clear that their mental and physical health will be negatively impacted. This assumption is confirmed by the observation that release from detention was associated with improved symptomatology [20].

The anxiety-inducing aspects of migration are not limited to family separation and detainment. Migration is a lengthy, overwhelming, and ongoing process for adults, which is exacerbated in young children who face unique societal and familial pressures. Acculturation stressors, or the mental and emotional challenges of adapting to a new culture, are prevalent in migrant children, often in the form of physical and mental health symptoms associated with perceived discrimination [17]. A child is often asked to enter a new environment with school-aged children who may not fully understand their migration experience or speak the same language as them. When David was placed in foster care facilities after his familial separation, he did not speak English yet, and nobody around him spoke his native languages of Spanish and Acatek [1]. David reported feeling isolated, as he was unable to process his trauma or connect with those around him [1]. When children are forced into these new environments without support, it causes heightened feelings of rejection, self-isolation, and anger even after they have already undergone migration-related trauma.

Although internal neuroanatomy may change within a migrant child’s brain, it is common for the anxiety, depression, and poor mental health of migrant children to manifest itself

externally. This can be shown through aggressive behaviors towards peers and family members, isolation methods, and low performance in school [21]. According to psychologist Mary Ainsworth’s research model, infants who are separated from their mothers respond in several ways after they are reunited [22]. She found that children could have secure attachment styles, where the child feels safe and confident; ambivalent-insecure attachment, where the child feels angry and unsociable; or avoidant-insecure attachment, where the child feels emotionally isolated and rejected [22]. In an interview conducted with a mother who was separated from her child during the zero-tolerance policy, the mother wept that her child was upset and disinterested with her upon reuniting. This reaction suggests that the child suffered psychological damage, showcasing an ambivalent or avoidant attachment [23]. The child’s behavior is an example of how migrant children may cope with their traumatizing migration experiences. The outcome varies for each child, yet long-lasting psychological and behavioral changes in adolescent migrants are usually guaranteed after traumatic migration experiences.

Mother-Infant Social Attachment and Opioid Systems Mice studies have shown that a lack of mother-infant bonding, similar to what separated migrant children may experience, leads to abnormal opioid systems in later adulthood [24]. The opioid system regulates numerous physiological functions, including responses to stress, respiration, and endocrine and immune functions [25]. Opioid binding sites are expressed throughout the brain, and if damaged, lead to changes in mood regulation and well-being. This finding verifies how early life trauma related to child-caregiver separation can lead to complex biological alterations in various areas of the body. The brain opioid hypothesis of social attachment proposes that reductions in opioid activity should increase the desire for social companionship, whereas increases in this system should reduce the need for attachment. This suggests that the attachment between mother and child activates the opioid system and may mirror the effects of opium—euphoria and reward [25]. Without this relationship, the opioid system is inactivated, leaving a child longing for this type of feeling. Mice with μ-opioid receptor knockout genes (MOR-KOs), meaning they lack genes coding for opioid receptors and thus have limited opioid activity, have shown issues in the formation of mother-pup relationships. Animals treated with blockers that prevent the effects of opioids such as naloxone and naltrexone (NTRX) have shown similar effects, experiencing decreased affiliation and desire for attachment [24]. These findings suggest that disruption of the child-caregiver relationship has a biological basis rooted in opioid system abnormalities that will negatively affect a child’s current and future interactions.

Mice lacking these genes showed reduced interest in their social partners and diminished time spent in social interaction zones in laboratory settings [26]. This finding provides insight into how a migrant child may navigate social situations after immediate separation from their mother. Both heterozygous and homozygous MOR-KOs showed decreased social interaction and anxiety-like behavior when placed in a setting focusing on social activity [27]. Researchers assessed social behaviors like nose-to-nose interaction, huddling with partners, and social exploration, and they found that these decreased in MOR-KOs [27]. MOR-KOs interacted less with wild-type mice in a direct social interaction test, and spent more time self-grooming [28]. Self-grooming is a personal, self-induced process that may mimic self-isolation in humans. This finding may suggest that, like these mice pups, migrant children who have undergone familial separation may choose to remain isolated rather than engage in social interaction with others. The aforementioned child’s disinterested response to his reunion with his mother after months of separation coincides with this animal study’s findings [23]. Not all children, however, will act with disinterest in social interactions after a traumatic event like family separation.

In the same study, MOR-KOs were significantly more violent in a resident-intruder test [28]. Male MOR-KOs were isolated four weeks before another male was introduced into their home cage. In contrast with normal mice, MOR-KOs engaged in an increasing number of attacks toward the intruder mice [28]. This increase in violence and aggressive tendencies

may be how the mouse pup “acts out” as a result of early life stress. A migrant child may act in the same way, putting strain on familial relationships after undergoing an already stressful and disheartening event like family separation. Family separation is not an isolated event whose effects can easily be remedied and forgotten; instead, family separation causes lasting strife for both migrant children and their families.

Migration is a process reliant on change: a change of environment, of relationships, and ultimately, of lifestyle. When migration becomes traumatic, it leaves lasting effects by disrupting healthy neurodevelopment and altering brain function. The trauma induced by family separation undoubtedly jeopardizes the health and wellness of migrant children [29]. Although long-term studies are scarce due to the recent nature of the zero-tolerance policy, former case studies within institutional settings and animal-based research have provided insight into the consequences of traumatic separation. Testimonies like that of David and his family prove family separation is inhumane. The U.S. immigration system has psychologically damaged its victims, leaving negatively-associated brain changes that have the capacity to remain for a lifetime and impact all spheres of a migrant’s life: physical, social, and emotional [29]. Families must remain united regardless of differences in legal status, as the disruption of the child-caregiver connection is detrimental to the health of all members of a familial unit. The comfort and love provided by a familial bond has no borders and must be preserved.


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