How the Anxiety Reaction Starts in the Brain


The following information is based on the latest discoveries revealing how the anxiety/fear reaction manifests itself in the brain. This step-by-step progression of an anxiety response is common to anyone suffering from anxiety, panic attacks or phobias:

  1. When you perceive danger (usually through sight and sound), whether it’s a noise, image or an unpleasant feeling or sensation, this information takes two different paths:
    • The amygdale, the emotional center of the brain, is activated causing sweaty palms, accelerated heart, dizzy feeling, etc. This adrenalized state kicks in a fraction of second, following the shortcut path, beforeyou realize you saw, heard or touched something. This means that before you know what you are afraid, you feel it! This means that, contrary to popular belief among psychotherapists, you cannot stop nor prevent this reaction with your thoughts alone.
    • Thus only after the fear/anxiety reaction has kicked in, your conscious mind enters into action. Some of the information received from the senses, don’t go to the amygdale. They rather end up thalamus, a by-station from the sensory organs to the cerebral cortex sensory regions. It has a somato-sensory mapping of the body and has integrative functions. Then travels to the cortex to be analyzed. If it considers it appropriate orders the cortex signals the amygdale which in turn mobilizes the body for action: fight or flight.

  2. The visual, auditory, information (whether real or imaginary) is sent partly to amygdala (unconscious) or cortex (conscious). The latter filters a small portion of this sensory information to the analyzing part of the brain.
  3. The olfactory or tactile information (whether real or imaginary) are sent directly to the amygdale. This explains why smells or sensations can trigger anxiety with more power than images or sounds.
  4. The thalamus analyzes the detailed quality of the images in terms of color, hues, form and dimension. And does the same for sounds, i.e. their volume, pitch, etc. All these details information of visual and auditory impulses are sent to the cortex.
  5. The cortex allows the brain to become conscious of sounds and images. The prefrontal cortex has the capacity to interrupt the anxiety/fear reaction.
  6. Amygdala, the region of the brain, located in the medial temporal lobe, which plays a key role in the emotions, kicks in the fear reaction. Any sensory input that goes to the amygdale becomes emotionally charged.
  7. Basal ganglia, a concentrated group of neurons, are several ganglia that work together to induce motivation and coordinate physical movement with the emotion. to reach a goal. If the amygdale kick starts the fear/anxiety reaction, the basal ganglia cranks it up, causing the anxiety reaction last for a long time.
  8. Locus coeruleus is activated by the signal from the amygdale. It is responsible for the typical physiological responses to anxiety, fear and panic such as pounding heart, sweating, stomach upset or dizziness, tremors and twitches.
  9. The hippocampus, the memory center off the brain, stores the emotionally charged experience.
  10. Up to here we saw how the perception of a menacing object or situation activates the amygdala. Now let’s look at how your body reacts under the influence of a series of hormonal changes:
  11. The adrenal glands segregate large doses of cortisol, a stress hormone. This “overdose” interferes with the correct coping of a stressful experience. Moreover an excess amount of cortisol affects the function of the hippocampus, which prevents normal memory function. If the anxiety is long term, the effects of cortisol on the hippocampus impairs the creation of coherent memories.
  12. This increase of hormones makes your heart beat faster, your breathing to increase, your blood pressure go up and get “goose pumps” .
  13. Adrenaline is diverted toward the muscles mobilizing the body to fight the potentially dangerous object/person or situation, or flee from it.

The above information shows the fact that fear or anxiety kicks off before and independently of your being conscious of it. This means that you cannot stop or prevent a phobia with your will power!

A number of hormones are responsible for the symptoms of panic. Before we see what theses hormones are, let’s look at the most common signals of our inbuilt alarm system.