The neuroscience of fear, memory, and the human capacity to return to safety in unpredictable times
By Marina Savic-Baines
Founder, Nervous System Energetics™
In times of uncertainty, many people experience sudden waves of anxiety, tension, or emotional overwhelm. These reactions are often misunderstood as weakness or overreaction. In reality, they are biological responses produced by the brain and nervous system when the future becomes unpredictable.
Understanding how these systems function helps us approach fear with greater awareness and compassion. It also reveals something important: the human nervous system possesses a remarkable capacity to return to stability, even during periods of uncertainty.
Fear, memory, and the remarkable capacity of the human nervous system to return to stability
Twelve days ago we heard explosions above our home in Dubai. Air defence systems had intercepted missiles in the sky, and for several seconds the sound travelled across the city before the air returned to silence.
What struck me most about that moment was not the sound itself, but the speed with which my body responded.
Before my mind had time to interpret what was happening, my nervous system had already reacted. My breathing changed abruptly. My chest tightened, and a wave of panic moved through me with an intensity that felt both immediate and strangely familiar. I instinctively moved closer to my husband and began crying. The words that came out of my mouth surprised me because they came from somewhere deeper than conscious thought: “I don’t want to go through this again.”
In that moment it became clear that my reaction did not belong only to the present situation.
It belonged to memory.
More than two decades earlier, in 1999, I lived through a period of war in my home country, Serbia, when bombing campaigns were part of everyday life for months. Although those events ended many years ago, the nervous system retains an extraordinary capacity to store sensory impressions associated with intense experiences. Sounds, smells, and bodily sensations connected with past danger can remain encoded within neural circuits long after the conscious mind believes the event has been processed and left behind.
Neuroscience refers to this phenomenon as implicit or somatic memory. Unlike explicit memories, which we can recall as stories or images, implicit memories are stored in neural networks that influence bodily responses and emotional reactions without necessarily entering conscious awareness. These memories are expressed through the body: a tightening of muscles, a change in breathing, a sudden emotional response that seems to arise before thought has time to intervene.
When the explosions echoed above our home in Dubai, my nervous system recognised something long before my rational mind did.
Yet what happened next was very different from what I experienced many years ago.
Over the past two decades I have spent a significant amount of time studying and working with the nervous system. Through breath regulation, emotional awareness, and somatic practices I learned to recognise the physiological signals that indicate the nervous system has entered a state of alarm. Instead of trying to suppress the reaction or force myself to remain calm, I slowed my breathing deliberately and directed my attention toward the sensations in my body.
Within a few minutes the intensity of the panic began to soften. My breathing deepened, my heart rate slowed, and the nervous system gradually returned to a state of relative equilibrium.
The fear moved through me without taking control of the rest of my day.
This experience illustrates something important about human biology. Two individuals can encounter the same uncertain situation and respond in dramatically different ways. One person may remain trapped in anxiety long after the moment has passed, while another may regain stability relatively quickly.
The difference is rarely personality or strength.
More often, the difference lies in the capacity of the nervous system.
To understand why uncertainty affects human beings so deeply, it is necessary to examine how the brain processes unpredictability and why the nervous system reacts so strongly when the future becomes unclear.
The Brain Is Not Designed for Certainty
The human brain evolved primarily to keep us alive in environments where danger was often sudden and unpredictable. For hundreds of thousands of years survival depended on the brain’s ability to detect potential threats quickly and mobilise the body before conscious thought had time to intervene.
At the centre of this system lies a small almond-shaped structure deep within the brain known as the amygdala. The amygdala functions as an early warning system that continuously scans incoming sensory information for signs of potential danger.
What makes the amygdala particularly powerful is its sensitivity to ambiguity.
The amygdala does not wait for certainty before reacting. Instead, it responds to possibility. If a sound is sudden or unfamiliar, if an environment feels unpredictable, or if signals from the outside world suggest that something may not be safe, the amygdala activates rapidly.
This activation occurs through neural pathways that connect sensory information directly to emotional processing centres in the brain. In many cases this pathway operates faster than the circuits responsible for rational analysis.
From an evolutionary perspective this design makes sense. Early humans who reacted quickly to uncertain signals in their environment were more likely to survive than those who waited for complete information before responding.
Once activated, the amygdala sends signals to another structure in the brain called the hypothalamus, which initiates a cascade of physiological processes known collectively as the hypothalamic-pituitary-adrenal axis, or HPA axis.
The HPA axis releases stress hormones such as adrenaline and cortisol into the bloodstream. These hormones prepare the body for action by increasing heart rate, sharpening attention, and redirecting energy toward muscles that may be required for rapid movement.
In a matter of seconds the body shifts into what is commonly known as the fight-or-flight response.
This response is extraordinarily efficient from a survival perspective.
However, in modern environments these same biological systems are often activated not by immediate physical danger but by uncertainty itself.
Why Uncertainty Can Be More Stressful Than Danger
One of the most surprising discoveries in contemporary neuroscience is that uncertainty can produce stronger emotional responses than clearly defined threats.
Research conducted at University College London examined how the brain reacts when individuals anticipate a potentially unpleasant event. Participants were placed in situations where they might receive a mild electric shock. In some trials they knew with certainty whether the shock would occur. In others the outcome remained uncertain.
The results revealed something remarkable.
Participants displayed significantly higher levels of anxiety when they were uncertain about whether the shock would occur than when they knew the shock would definitely happen.
The brain struggled more with unpredictability than with the negative event itself.
This phenomenon reflects the brain’s fundamental role as a prediction system.
Modern neuroscience increasingly describes the brain as a predictive organ that constantly attempts to anticipate what will happen next. By analysing patterns in the environment and comparing them with past experiences, the brain generates expectations about the future.
When these predictions become difficult because information is incomplete or contradictory, the brain increases its level of vigilance.
The prefrontal cortex, responsible for reasoning and planning, attempts to analyse available information and generate possible outcomes. At the same time, the amygdala continues scanning for signals of potential danger.
This interaction can create a powerful feedback loop between emotional and cognitive brain networks.
People often experience this internally as racing thoughts, repeated checking of news updates, heightened alertness, and difficulty relaxing.
The brain is not simply responding to what is happening in the present moment.
It is attempting to anticipate what might happen next.
Why Mothers Often Experience Uncertainty More Intensely
Periods of uncertainty can be particularly challenging for mothers, and neuroscience offers important insights into why this is the case.
Pregnancy and early motherhood trigger profound biological changes in the brain. Neuroimaging studies have shown measurable structural changes in brain regions associated with emotional processing, empathy, and threat detection. These changes are believed to enhance caregiving capacity by increasing sensitivity to signals related to safety and wellbeing.
Research conducted at institutions such as Leiden University and Yale School of Medicine has demonstrated that the maternal brain undergoes neuroplastic adaptations that strengthen neural networks involved in bonding and protective behaviour. Areas of the brain involved in emotional attunement and vigilance become more responsive after childbirth.
From an evolutionary perspective, this adaptation is essential.
Human infants are highly dependent on caregivers for survival, and the maternal brain becomes biologically oriented toward monitoring environmental conditions that may affect the child’s safety. Mothers often develop heightened awareness of subtle signals in their environment, including changes in sound, movement, or emotional tone.
While this increased sensitivity supports caregiving, it can also intensify emotional responses during periods of uncertainty.
When external conditions feel unpredictable whether due to geopolitical tension, alarming news, or sudden disruptions to daily life the maternal brain may interpret these signals through a protective lens that includes the wellbeing of children and family members.
This expanded field of concern can amplify vigilance and emotional reactivity.
In other words, mothers are not only regulating their own nervous systems. They are often regulating the nervous systems of their children as well.
Neuroscientists sometimes refer to this phenomenon as co-regulation, the process through which the emotional and physiological states of caregivers influence the developing nervous systems of children. Infants and young children rely heavily on the emotional stability of caregivers to help regulate their own stress responses.
For this reason, when mothers experience heightened anxiety during uncertain periods, it is not simply a personal emotional reaction. It reflects the brain’s caregiving circuitry responding to perceived responsibility for protecting others.
Understanding this biological reality can be deeply reassuring.
The heightened awareness many mothers feel during uncertain times is not a sign of weakness or fragility. It is a reflection of the brain’s remarkable ability to reorganise itself around the needs of caregiving.
Fear Is Not Only Psychological — It Is Physiological
Fear is often described as an emotional state, yet from a biological perspective it is primarily a physiological condition involving multiple systems throughout the body.
When the brain detects potential danger, the sympathetic branch of the nervous system initiates a cascade of bodily responses designed to prepare the organism for action. The heart begins beating faster to circulate oxygen and glucose to muscles that may be needed for movement. Breathing becomes quicker and shallower to increase oxygen intake. Muscles tense in anticipation of rapid action.
At the same time, processes that are not immediately necessary for survival temporarily slow down. Digestion decreases, the immune system shifts into a different mode of functioning, and attention becomes narrowly focused on potential threats.
These physiological changes are not signs that something is wrong.
They are signs that the body is preparing itself for survival.
However, when uncertainty persists over long periods, the nervous system may remain in a state of prolonged activation. This sustained physiological alertness can lead to symptoms such as muscle tension, fatigue, headaches, digestive disturbances, and difficulty sleeping.
These symptoms often cause people to believe something is wrong with their health, when in reality they are experiencing the biological consequences of a nervous system that has been maintaining a heightened state of vigilance.
Recognising these reactions as physiological rather than purely psychological can reduce the sense of helplessness many people feel during stressful periods.
The body is not betraying us.
It is attempting to protect us.
The Nervous System Also Contains Powerful Systems for Recovery
While the brain contains highly efficient systems for detecting danger, it also contains equally sophisticated mechanisms designed to restore safety and equilibrium.
The parasympathetic branch of the nervous system plays a central role in this process. This system supports recovery, rest, and physiological regulation after a stress response has occurred.
One of the most important pathways involved in parasympathetic regulation is the vagus nerve, the longest cranial nerve in the human body. The vagus nerve connects the brain to multiple organs including the heart, lungs, and digestive system, creating a communication network that helps regulate many essential bodily functions.
When the vagus nerve becomes active, it signals safety to the nervous system. Heart rate slows, breathing deepens, muscles begin to relax, and the body gradually transitions out of survival mode.
Neuroscientist Stephen Porges, through his work on polyvagal theory, has described how the vagus nerve helps regulate social engagement, emotional connection, and the capacity to feel safe in the presence of others.
Practices that support vagal activation include slow diaphragmatic breathing, gentle physical movement, meaningful social interaction, and environments that signal safety to the nervous system.
These practices are not merely psychological techniques.
They are biological signals that help the nervous system recalibrate.
Neuroplasticity and the Brain’s Capacity for Resilience
Perhaps the most hopeful discovery in modern neuroscience is the concept of neuroplasticity, the brain’s ability to reorganise and adapt throughout life.
For many years scientists believed that the brain’s structure remained largely fixed after early childhood. Research over the past several decades has shown that this assumption was incorrect. Neural networks continue to change throughout adulthood in response to experience, learning, and environmental influences.
This means that the brain’s response to stress and uncertainty is not permanently fixed.
With consistent practice and supportive environments, the brain can strengthen pathways involved in emotional regulation and reduce the intensity of threat responses.
Studies examining mindfulness practices, breath regulation, and somatic awareness have demonstrated measurable changes in activity within brain regions involved in emotional regulation, including the prefrontal cortex and limbic system.
These findings suggest that resilience is not simply a personality trait that some people possess while others do not.
Resilience is a capacity that can be cultivated.
A Human Perspective on Uncertain Times
Periods of uncertainty remind us that the human nervous system is deeply connected to the world around us. Sudden sounds, alarming news, or unpredictable events can activate biological systems that evolved long before modern society existed.
When we understand what is happening inside the brain and body, these reactions begin to make sense. Fear is no longer something we need to fight against or feel ashamed of. Instead, it becomes a signal information from the nervous system asking for attention, care, and regulation.
Resilience is often misunderstood. It is not the absence of fear, and it is not the ability to suppress emotional reactions. True resilience is the nervous system’s capacity to move through activation and return to stability.
The encouraging truth is that this capacity can be strengthened.
The brain and nervous system are remarkably adaptable. With the right understanding, practices, and support, the body can learn to recognise safety again even in uncertain environments.
In the past days I have received messages from many people who feel unsettled, anxious, or overwhelmed by the events unfolding around them. These reactions are deeply human. When the nervous system perceives unpredictability, it naturally tries to protect us.
If you find yourself feeling dysregulated during uncertain times, know that you are not alone and that your nervous system is not working against you. It is trying to keep you safe.
Sometimes the most powerful step is simply allowing space for the body to settle again.
If you feel you would benefit from guidance, support, or a conversation about nervous system regulation during this period, I am here to help.
Scientific References
LeDoux, J. (2012). Rethinking the emotional brain. Neuron.
Grupe, D. & Nitschke, J. (2013). Uncertainty and anticipation in anxiety. Nature Reviews Neuroscience.
Hoekzema, E. et al. (2017). Pregnancy leads to long-lasting changes in human brain structure. Nature Neuroscience.
Porges, S. (2011). The Polyvagal Theory. Norton.
UCL Institute of Cognitive Neuroscience research on uncertainty and stress responses.
