Have No Fear, Your Hidden Fear Response Regulators Are Here: How Our Caregivers Shaped Our Fear Regulation System
Lotus Lichty
Illustrations by: Sneha Das
Imagine you are two years old and going to a relative's house for the holidays. As you enter through the door, the aroma of freshly baked sugar cookies fills the air, and the crackling fire gently warms your face. Everything is tranquil. Suddenly, a colossal creature with floppy ears comes bounding over to you out of the blue. Your pupils dilate and your heart starts to race a mile a minute. You quickly rush to your parents, nestling yourself in their arms so they can protect you from the terrifying beast. If you were not raised with a pet, this may have been your first encounter with a dog. It may seem obvious that your parents played an important role in calming you down when you became distressed during new and frightening situations. What may not be as obvious is that when your parents comforted you, they actually shaped how your fear regulation system, the system that helps you respond to scary situations, developed. By creating a nurturing and safe environment for you to initially experience fear, your parents critically influenced the formation of the neurological processes and structures that underlie your ability to regulate stress in your mind and body later in life.
Critical Periods: A Critical Concept in Caregiving
A child’s brain is like play-doh, pliable and easily molded by external factors. Though it is difficult to remember your early childhood experiences, the close emotional connections you shared with your caregivers during this time shaped who you are today. At birth, your brain contains billions of neurons, or cells that can transmit information. However, despite being born with these billions of neurons, you were not born with the neuronal connections needed to perform essential life skills, like coping with novel stressful situations. In order to build these connections, there are specific periods of time — dubbed “critical periods” or “sensitive periods” — in which the brain is especially sensitive to rapid restructuring and rewiring [1]. These periods are essential for your development, as they lead to the acquisition of critical skills such as language, movement, and emotion regulation. Since technical and ethical limitations make it difficult to study these discrete windows of time, we don’t know when exactly critical periods occur. Nevertheless, it appears the brain has a critical period sometime between birth and age three [1, 2]. Because children are dependent on their caregivers for survival during the first three years of their life, their brain primarily receives inputs from interactions with their caregiver. Therefore, caregiver interactions can significantly influence how the brain develops, given that environmental input received during critical periods can drastically and enduringly change the brain [1,3]. A pivotal way that parents mold your brain early in life is by shaping the neural circuitry of your fear regulation system during critical periods. To better understand how your interactions with your parents influence the development of your brain, let’s take a look at how the fear regulation system works.
Should I Stay Or Should I Go: The Fear Regulation System
When you encountered a dog for the first time — whether it was at your relative’s house for the holidays or during a walk around the neighborhood — you probably didn’t see a friendly, fluffy creature. Instead, you saw an outlandish beast twice your size. The dog most likely caused you to feel fear, which made you want to flee. But what causes this sensation of fear? When there is a threatening stimulus in the environment, the amygdala, a region of the brain that processes fear, responds [4, 5]. The amygdala has evolved to detect and immediately respond to threats or dangers in the environment. During childhood, when everything is new and the need to learn what is safe is great, the amygdala is very active [6]. Therefore, the first time you met a dog, your amygdala detected that this stimulus was unfamiliar and responded.
In response to amygdala activation, another brain region called the hypothalamus acts like a mailman, receiving the message of a nearby threat from the amygdala and sending it to the rest of the body. Through a series of chain reactions, the hypothalamus prepares the body for the perceived threat by making you more alert. The hypothalamus triggers the release of stress hormones adrenaline and cortisol; these hormones make your pupils dilate and your heart race a mile a minute when you first meet a dog [5]. Collectively, these physiological and physical changes make up our fear response. Taken together, when you encounter something stressful in the environment, your amygdala initiates the fear response to help your body prepare for the perceived threat. However, while the amygdala can protect you from real dangers in the environment, it does a poor job discriminating between a real threat and a false alarm [7, 8].
In order to distinguish between real threats and false alarms, the amygdala needs to form a connection with our brain’s “emotional control center,” the medial prefrontal cortex. While the amygdala sounds the alarm for fear-inducing stimuli, the medial prefrontal cortex helps us determine if the alarm is justified [7,8]. However, connectivity between these two brain regions does not mature until around adolescence [8]. Therefore, as a child, you did not have the cognitive ability to accurately judge whether or not an environment was safe. The ability to discriminate between a real imminent threat, such as a venomous snake, from a perceived or imagined threat, such as a big gentle dog, is critical for survival. The brain must be able to determine whether something is actually dangerous; otherwise, your fear response would be constantly activated. When caregiving is insufficient, this circuit between the amygdala and the medial prefrontal cortex does not always develop properly, and neither does your ability to distinguish between real and imagined threats.
The Fear Regulation System On Overdrive
Children who are used to living in a stressful environment (i.e. one that lacked consistent, responsive caregiving) may not be able to acclimate to a safer environment with dependable caregivers. The consequences of this shift can be seen most clearly among children after they have been adopted. When compared to non-adopted children, adopted children have larger amygdalas [6, 9, 10]. It is possible that this is because their amygdalas have begun to develop sooner due an early absence of comfort during stressful situations [6, 9, 10]. Oftentimes, children raised in orphanages do not have stable caregivers since care is limited and often fluctuates. Therefore, children who experience prolonged negative caregiving experiences may have to “grow up” faster; their brains begin to develop sooner to form the connections needed to cope with stressful situations independently [7]. In the absence of a stable caregiver, faster maturation of the amygdala may be adaptive because it can facilitate adult-like fear learning and avoidance, such as learning not to eat spoiled or toxic food. This “fear learning” and avoidance can help children navigate stressful environments, thereby increasing their chance of survival [7]. However, while accelerated development of the amygdala may be adaptive in adverse environments, it may be maladaptive in safe environments. Children that have larger amygdalas may be more sensitive to cues for danger than their peers, making them more anxious. These children may generally feel more apprehension or dread because they see the world as a dangerous or stressful place [11]. If you had insufficient caregiving and met a dog for the first time, even when you were no longer in the presence of the giant, fluffy “beast,” your feelings of stress and danger may have lingered.
Since the brain is an intricate and complex organ, its development must not be rushed. Researchers have proposed that premature development of the amygdala may initiate premature connectivity to the medial prefrontal cortex, disrupting proper connectivity between the two brain regions [8]. This lack of connections ultimately reduces the brain’s ability to regulate the fear response [7]. In turn, this phenomenon can hinder the order of regular connectivity development between the amygdala and medial prefrontal cortex [12]. For example, it may be that the medial prefrontal cortex develops sooner in an attempt to keep the amygdala in check. However, if this circuit develops at an accelerated rate, it will not be as effective at reducing fear responses after the stressor has passed; this prevents an individual from orienting towards more goal-directed behavior, such as deep breathing, to help them calm down [12]. Notably, parents can help children navigate stressful environments by reducing fear responses, effectively preventing this disruption of normal maturation. Early parental deprivation is linked to premature development of this circuitry, impacting a child’s ability to deal with difficult situations later in life. Responsive caregivers equip children with the cognitive ability to cope with stressful situations on their own [7].
What’s Love Got to Do with It?: How Parents Regulate Fear Response
Although you may have been terrified of the unfamiliar dog at first, you most likely calmed down after your parents held and comforted you. Your parents may have pet the dog to show you that it was friendly rather than dangerous. After some time, you may have even felt brave enough to pet the dog yourself, as long as your parents were nearby. This situation is an example of parents providing sensitive caregiving — that is, they were attentive to your needs [13,14]. Sensitive caregivers can make children feel safe and secure by calming them down in the presence of environmental stressors [15].
When a child and a caregiver interact, a hormone important in strengthening the parent-child bond, called oxytocin, is secreted [16,17,18, 21]. A common example of child-caregiver bonding is when a mother makes baby-talk noises while her infant babbles. This phenomenon is called parental synchrony: a caregiver mimics or coordinates their behavior with the child's non-distress cues, such as touch, gaze, and vocal or facial expressions [19]. Parental synchrony may even look like a nuanced dance where the caregiver subtly responds to the child’s cues [20]. As the two interact, the levels of oxytocin — the “love hormone” — increase in both the child and the caregiver [21]. Oxytocin then attaches to its receptors found throughout the amygdala, causing the child to feel calmer when faced with a fear-inducing stimuli [22, 23, 24, 25]. Thus, parents may be able to calm their children’s stress response with their presence, which stimulates the secretion of oxytocin and effectively reduces amygdala activity.
Furthermore, when parents are able to facilitate the release of oxytocin and reduce their child’s stress response to threatening situations, the child is more likely to develop the proper circuitry important for emotion regulation. The calming effects of their presence promote proper connectivity between the child’s amygdala and medial prefrontal cortex. Sensitive caregiving enhances this connectivity by activating both brain regions simultaneously; if this activation occurs repeatedly, the circuitry between the amygdala and the medial prefrontal cortex is more likely to develop properly [6,7, 8]. This reciprocal connection is necessary because it supports effective fear regulation: the medial prefrontal cortex works to reduce the duration of the amygdala’s responses to false alarms. Medial prefrontal cortex-amygdala connectivity prevents feeling excessive or unwarranted fear, reducing the chance that a child may experience anxiety later in life. In sum, caregivers’ sensitivity shapes the strength and nature of amygdala-medial prefrontal cortex connectivity development, in turn, influencing their child’s stress management skills.
Help, I Need Somebody! Not Just Anybody
Think back to when you first encountered that scary dog. Having your parents guide you through this fear-inducing experience created long-lasting influences on how you perceive and respond to threats in your environment. We have all developed coping mechanisms to help us ease our nerves before, during, and after stressful situations, whether it be listening to music to distract ourselves or pacing around the room and taking deep breaths. Whatever coping mechanisms you use today may be effective because your early caregivers equipped you with the mental capacity to calm yourself down. So, the next time you find yourself taking a deep breath to calm down before giving an oral presentation or going to a job interview, you may have your parents to thank.
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