Exploring the Connection Between Anxiety and the Brain
Published: 19/12/2023
Written by: Creyos
Among mental health concerns in the general population, anxiety stands out as one of the most prevalent. Physicians and psychologists have to field anxiety concerns across almost every other issue they encounter. Even so, its prevalence is not fully known, as many people do not seek help for anxiety or clinicians may not have enough information to make the diagnosis.
According to one recent review of anxiety:
- Specific phobia claims the highest prevalence, with a 12-month prevalence rate of 12.1%
- Following closely is social anxiety disorder, with a 7.4% prevalence rate over the same period
- Agoraphobia ranks as the least common anxiety disorder, with a 12-month prevalence rate of 2.5%
- Notably, anxiety disorders exhibit a higher frequency in females compared to males, maintaining an approximate ratio of 2:1.
With the pervasive nature of anxiety, clinicians have the challenging task of accurately pinpointing the causes of anxiety—as even being in a clinical setting can spark a patient’s anxiety! Their task becomes distinguishing between everyday anxiety, anxiety disorders, and their comorbid conditions.
Along with traditional subjective measures, such as clinical interviews, cognitive testing can help to paint a comprehensive picture of anxiety’s effects on the brain. By identifying changes in cognitive performance, healthcare providers can better understand the patient's experience and further investigate any underlying alterations in brain structure to tailor treatment strategies accordingly.
In this article, we’ll explore how anxiety affects the brain, how patients and physicians can recognize the symptoms, and what tools are available to manage anxiety more effectively and work towards a healthy brain.
Anxiety at a High LevelAnxiety is a multifaceted interplay between different brain areas, such as the amygdala, known as the emotional brain, and the prefrontal cortex, the area responsible for cognitive brain health. In an anxious brain, neural pathways become rigidly attuned to stress hormones, leading to physical symptoms like a rapid heartbeat or lightheadedness, all linked to the activation of the sympathetic nervous system—our body’s “fight or flight” response. |
What Are Anxiety Disorders?
Anxiety disorders are a group of mental health conditions characterized by feelings of worry, fear, and tension. It’s important for clinicians to support patients by distinguishing these from normal levels or temporary feelings of anxiety. These disorders come in various forms, each with its unique characteristics:
Panic Disorder
Panic disorder is a type of anxiety disorder characterized by sudden and recurrent episodes of intense fear, often accompanied by physical symptoms such as heart palpitations, shortness of breath, or dizziness. An estimated 2.7% of U.S. adults experienced a panic disorder in a twelve-month period.
This disorder can be compared to a fear response that has gone off track, with the amygdala and other limbic brain regions becoming hyper-activated, thereby causing a state of extreme anxiety even without any real threat.
Post-Traumatic Stress Disorder (PTSD)
Post-traumatic stress disorder (PTSD) is a mental health condition triggered by experiencing or witnessing a traumatic event, resulting in symptoms such as:
- Intrusive thoughts
- Flashbacks
- Nightmares
- Avoidance of triggers
- Hyperarousal
- Difficulty sleeping
- Irritability and anger
- Difficulty concentrating
According to the U.S. Department of Veterans Affairs, about 6% of the U.S. population (not limited to veterans) will have PTSD at some point in their lives. They also report that in 2020, about 13 million Americans had PTSD.
Read more about assessing PTSD symptoms with a standardized scale available in Creyos Health: PCL-5: Measure Self-Reported Post-Traumatic Stress Symptoms With the PTSD Checklist for DSM-5
Phobias
Phobias are characterized by persistent and excessive fear of specific objects, persons, or situations. Someone with a phobia will often go to great lengths to avoid what they fear, even if the fear is much greater than the actual risk.
Brain scans have shown that those with phobias have increased activity in certain brain regions, such as the dorsal anterior cingulate cortex, when exposed to the object of their fear.
Research findings reveal that specific phobias have a worldwide lifetime prevalence ranging from 3% to 15%, with the most common fears centering on heights and animals. Additionally, it's worth noting that phobias endure for extended periods, persisting for several years or even decades in 10–30% of cases.
Obsessive-Compulsive Disorder (OCD)
Obsessive-Compulsive Disorder (OCD), another subtype of anxiety disorder, is characterized by persistent and intrusive thoughts, known as obsessions, and repetitive behaviors or rituals, known as compulsions. These behaviors are often performed in response to these obsessions, leading to a vicious cycle.
According to the National Institute of Mental Health (NIMH), the lifetime prevalence of OCD among U.S. adults is 2.3%. Similarly, the International OCD Foundation estimates that about 1 in 100 adults in the United States, or between 2 to 3 million adults, currently have OCD.
Generalized Anxiety Disorder (GAD)
Generalized anxiety disorder (GAD) may be likened to a background noise of worry that never completely goes silent. It’s characterized by persistent and excessive worry about various aspects of life.
The prevalence of GAD among adults in the United States is estimated to be between 3.1% and 6.1% (ADAA, CDC). The ADAA found that women are twice as likely to be affected by GAD compared to men. Additionally, GAD frequently co-occurs with major depression.
Read more about assessing anxiety symptoms with a standardized scale available in Creyos Health: Measure Symptoms of Anxiety With Creyos Health's Computerized GAD-7
Common Symptoms of Anxiety
For clinicians, getting to the root of a patient’s anxiety is a challenge, as anxiety symptoms can be linked to many comorbid conditions. Effective diagnosis starts with listening to a patient’s concerns and paying attention to body language.
Patients may present describing a constant state of worry, always feeling tense and nervous, being unable to relax, and/or with a sense of doom looming overhead. Clinicians may suggest intervention when these are not just fleeting feelings but persistent ones that affect a patient’s everyday life and overall well-being.
Anxiety manifests in a multitude of ways, impacting both our physical and mental states. These symptoms can vary from person to person, and the duration or severity of the symptoms can also differ.
Symptoms of Anxiety |
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Cognitive |
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Cognitive processes, including
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What Are the Causes of Anxiety in the Brain?
The causes of anxiety are manifold, with multiple factors often at play simultaneously. They range from genetic predispositions and brain structure to environmental experiences and neurotransmitters. Each of these elements can contribute to the development and manifestation of anxiety disorders.
Genetic
Research suggests that genetics not only contributes to anxiety disorders in general but also influences the risk for specific types of anxiety disorders. However, the genetic component is incredibly complex, and the extent of it may be unclear.
Familial patterns do indicate a hereditary component in generalized anxiety disorder (GAD). However, one study also described how parents with GAD may also influence their children's perception of potential threats in the environment, such as conveying (directly or indirectly) messages that:
- The world is unsafe
- Uncertainty is difficult to tolerate
- Strong emotions are to be avoided
- Worry is a coping mechanism for dealing with uncertainty
A patient might benefit from discussing family history with their healthcare provider or therapist, to better understand the potential hereditary causes of their anxiety.
Brain Structure
The brain’s structure is intricately linked with anxiety. Research on the brain structure and anxiety suggests that the brain's limbic system, which includes the hippocampus, amygdala, hypothalamus, and thalamus, is responsible for emotional processing, and individuals with anxiety disorders may exhibit heightened activity in these areas.
It’s not just about the individual brain structures, but also about how they interact with each other. For instance, the amygdala sends signals to other parts of the brain, such as the hypothalamus and the brainstem, which control the body’s stress response. This communication between different brain regions can significantly influence the experience of anxiety.
Neurotransmitters
Neurotransmitters, the brain’s chemical messengers, play a vital role in anxiety. They convey information to the brain regarding emotional states, cognitive processes, and behaviors. There are various neurotransmitters that are involved in anxiety, such as:
- Serotonin
- Glutamate
- Gamma-aminobutyric acid (GABA)
- Cholecystokinin
- Adenosine
- Dopamine
- Norepinephrine
- Corticotropin-Releasing-Hormone (CRH)
These neurotransmitters have been implicated in mood and anxiety disorders, and their dysregulation can contribute to symptoms of anxiety. For example, glutamate has shown increased activity in patients with social anxiety disorder, while GABA has been found to be dysregulated in several anxiety disorders.
Understanding the role of neurotransmitters and brain structures can be useful to psychologists and physicians in communicating with patients. For those who benefit from “stepping out” of the experience of anxiety and learning about what’s happening in the brain, sharing this information can help a patient relate differently to their anxiety.
Traumatic Life Events
Experiencing traumatic life events can be a significant trigger for anxiety disorders. These events (such as sudden loss, natural disasters, violence, or war) may induce intense fear, horror, or helplessness and can lead to the development of disorders such as post-traumatic stress disorder (PTSD), panic disorder, and specific phobias.
In an online self-administered survey involving 2,953 adults from a national US sample, 89.7% of participants indicated experiencing exposure to at least one traumatic event (ADAA). The impact of traumatic events can be long-lasting, often leading to chronic anxiety. The constant re-experiencing of trauma, avoidance of trauma-related stimuli, and increased arousal associated with PTSD are all markers of this continued impact.
Exploring a patient’s personal history and traumatic life events is often integral to effective mental health care, especially in regard to treating anxiety.
Chronic Stress
Chronic stress can be a significant contributor to anxiety. Stressors, whether daily hassles or major life events, can activate our body’s stress response, leading to a constant state of “fight or flight.” Over time, this heightened state can lead to anxiety disorders, with the brain becoming overly sensitive to stress hormones and potential threats.
Some common stressors that can contribute to anxiety include:
- Work-related stress
- Financial difficulties
- Relationship problems
- Health issues
- Traumatic events
The impact of chronic stress on mental health is far-reaching. It can lead to physical health issues, such as sleeplessness and muscle tension, as well as psychological symptoms, such as difficulties with focus and concentration. Chronic stress can also exacerbate existing anxiety disorders, making it even more challenging to manage anxiety symptoms.
By bringing awareness to the causes of chronic stress that influence a patient’s anxiety, clinicians can recommend lifestyle changes that may address and relieve some of these issues. However, there may be factors beyond an individual’s control, in which case it might simply be beneficial to bring attention to how chronic stress impacts anxiety and the brain.
How do lifestyle factors influence ADHD?
Read our expert Q&A to learn more.
Comorbid Conditions
Anxiety often doesn’t exist in a vacuum. It can co-occur with other conditions, such as:
- Attention deficit hyperactivity disorder
- Obsessive-compulsive disorder (OCD)
- Depression
- Mood disorders
- Learning disorders
- Substance use disorder
- Bipolar disorder
For example:
- In one comprehensive comorbidity survey, it was discovered that approximately 18% of individuals with a substance use disorder (SUD) also fulfilled the criteria for an anxiety disorder. This pattern is thought to arise as individuals may turn to alcohol or drugs as a form of self-medication.
- Anxiety often coexists with another prevalent condition, autism spectrum disorder (ASD). In fact, anxiety disorders are present in 40 percent of cases involving ASD.
- In patients with ADHD, more than half of the patients in one study had at least one comorbid anxiety disorder. The presence of comorbid anxiety disorders was also associated with worse clinical presentation, including a history of suicide attempts, a higher disposition toward anger, a higher rate of hospitalization, and psychotic symptoms.
Finding the appropriate treatment to resolve comorbid symptoms might reduce the symptoms of anxiety at the same time. But this starts with having the tools to identify and independently address the comorbid condition, distinguishing it from anxiety and understanding the interaction.
Stress and Anxiety
Stress and anxiety are two sides of the same coin, often feeding off each other in a vicious cycle. Stress (which is usually triggered by an external event) can exacerbate anxiety symptoms, and the chronic worry and tension characteristic of anxiety can, in turn, lead to more stress.
The physiological responses to stress and anxiety are similar, involving the activation of the body’s “fight or flight” response. This can lead to physical symptoms such as increased heart rate and muscle tension, and cognitive symptoms such as irritability and difficulty concentrating.
Understanding the connection between stress and anxiety can be crucial in managing both effectively and maintaining good mental health.
Read more about assessing stress in patients with a standardized scale available in Creyos Health: Measure Personal Stress With the Perceived Stress Scale (PSS)
Fear and Anxiety
Fear and anxiety may be intertwined, and feel similar, but they are not the same.
- Fear is an intense physiological response to an immediate and identifiable threat, while anxiety is a reaction to the apprehension of an unspecified danger.
- While fear is a reaction to a present and discernible danger, anxiety is more about worrying about what could happen.
- This can be compared to the difference between being scared of a snake present in the room with you (fear) and the constant worry of potentially encountering a snake (anxiety).
Fear can trigger anxiety, activating parts of the brain like the amygdala, which is responsible for processing emotions. This activation can result in the experience of anxiety, making fear and anxiety closely connected in our brain’s response to perceived threats. Understanding this connection (and the differences) may help patients manage anxiety more effectively.
Gut-Brain Axis and Anxiety
The gut-brain axis, the bidirectional communication system between the gut and the brain, has been shown to play a role in anxiety. The brain sends signals to the gut, and the gut sends signals back to the brain. This communication can influence various aspects of health, including mental health and digestion.
Interestingly, the gut microbiota have also been implicated in anxiety. These microorganisms can affect the production of neurotransmitters, the brain’s chemical messengers, influencing our mood and behavior. Disruptions in the gut microbiota, due to factors like diet or antibiotics, can potentially impact the gut-brain axis and contribute to anxiety.
Measuring the Cognitive Impacts of Anxiety on the Brain
Measuring the cognitive impacts of anxiety on the brain is a crucial step in understanding and treating anxiety disorders. Computerized cognitive assessments can serve as a complementary tool to subjective measures, providing a more comprehensive picture of anxiety’s effects on the brain.
Tools like the GAD-7 and the Perceived Stress Scale (PSS) can be used to evaluate patient health, track treatment progress, and substantiate treatment efficacy. These cognitive healthcare solutions can help healthcare providers to better understand their patients’ experiences, tailor treatment strategies, and monitor progress over time. They can also support patients in understanding their condition and feeling empowered in managing their anxiety.
Creyos Health provides a suite of cognitive assessments that helps clinicians measure anxiety and its role in other conditions.
Benefits for patients:
- An engaging experience with gamified tasks linked to specific brain regions
- Self-guided assessments that can be taken remotely and with minimal supervision
- Easy-to-understand results allow patients and families to be more proactive in their care
- Reimbursable evaluation under most insurance
Benefits for providers:
- Reliable and scientifically validated cognitive assessments used in over 300 peer-reviewed studies
- Easy to administer across using automated appointment scheduling
- Includes standard mental health questionnaires for many self-report measures
- Customizable to meet a variety of patient needs ranging from sound settings to time limits
Final Thoughts: Putting Feelings of Anxiety Into Words and Data
Anxiety, a complex interplay of genetics, brain structure, neurotransmitters, and environmental factors, goes beyond the mere feeling of being anxious.
This condition can significantly alter patients’ daily lives, influencing their thoughts, emotions, and interactions. Grasping its influence on the brain, along with utilizing the tools available for measuring and identifying its causes, is vital for managing this widespread condition.