Article
May 28, 2024 / by Marcella Peixoto
Inside The Anxious Mind: How does the brain work?
Anxiety is way more complex than many people know. Neuroscience has provided significant insights into the mechanisms underlying anxiety, revealing how certain brain structures and neurochemical processes contribute to this heightened state of worry and fear.
The Role of the Amygdala
The amygdala is central to the experience of anxiety. It is responsible for detecting threats and triggering emotional responses. In individuals with anxiety, the amygdala is often hyperactive, meaning it overreacts to potential threats. This hyperactivity can lead to excessive fear and worry, even in situations that are not truly dangerous.
Studies using functional magnetic resonance imaging (fMRI) have shown that people with anxiety disorders often have increased amygdala responses when exposed to stressors or anxiety-inducing stimuli. This overreaction can result in a constant state of alertness, as the brain continually signals that there is danger present, even when there is none.
The Prefrontal Cortex and Regulation
While the amygdala generates fear responses, the prefrontal cortex (PFC) helps regulate these emotions. The PFC, located in the front part of the brain, is involved in higher-order functions such as decision-making, problem-solving, and controlling impulses. In a healthy brain, the PFC works to moderate the amygdala’s responses, ensuring that fear and anxiety are kept in check.
However, in an anxious brain, the connection between the PFC and the amygdala can be weakened or dysregulated. This means the PFC has a reduced ability to calm the amygdala, leading to prolonged and intense feelings of anxiety. Individuals with anxiety disorders often have less activation in the PFC when faced with stress, making it harder for them to rationalise their fears and manage their anxiety.
Neurotransmitters and Anxiety
Neurotransmitters are the brain’s chemical messengers and also play a crucial role in anxiety. Key neurotransmitters involved in anxiety include:
1) Serotonin: Often dubbed the "feel-good" neurotransmitter, serotonin is essential for regulating mood and anxiety. Low levels of serotonin are commonly associated with anxiety and depression.
2) Gamma-Aminobutyric Acid (GABA): GABA is an inhibitory neurotransmitter that helps reduce neuronal excitability. It has a calming effect on the brain, promoting relaxation and reducing anxiety.
3) Norepinephrine: This neurotransmitter is associated with the body's "fight or flight" response. Elevated levels of norepinephrine can increase arousal and alertness, contributing to the physical symptoms of anxiety such as increased heart rate and sweating.
The Impact of Chronic Anxiety
Chronic anxiety can lead to structural and functional changes in the brain. Prolonged exposure to stress hormones like cortisol can damage the hippocampus, a brain region involved in memory and learning. This can impair cognitive functions and exacerbate anxiety, creating a vicious cycle.
Additionally, chronic anxiety can lead to neural plasticity changes, where the brain’s neural pathways are altered. This can make the brain more prone to anxiety, making it harder for individuals to break free from anxious thought patterns and behaviours.
The anxious brain operates through a complex interplay of hyperactive threat detection, weakened regulatory control, and imbalances in key neurotransmitters. Understanding these mechanisms is crucial for developing effective treatments and interventions. By targeting the specific brain regions and neurochemical processes involved in anxiety and using the right strategies to deal with.
....
References
The Pain of Worry: The Anxious Brain, link here
Neuroanatomy of Anxiety: A Brief Review, Published online 2018 Jan 12. doi: 10.7759/cureus.2055