Under long-lasting stress conditions, sustained hyperactivated HPA axis and the consequent high circulating glucocorticoids levels can lead to structural and functional disruption in amygdala via activating specific receptors (Gray and Bingaman, 1996).
After the amygdala sends a distress signal, the hypothalamus activates the sympathetic nervous system by sending signals through the autonomic nerves to the adrenal glands. These glands respond by pumping the hormone epinephrine (also known as adrenaline) into the bloodstream.
The functions of the amygdala, hippocampus, and the prefrontal cortex that are affected by emotional trauma can also be reversed. The brain is ever-changing and recovery is possible.
The amygdala is located in the temporal lobe of the brain. If you have a seizure that affects this area, your amygdala might be damaged. Temporal lobe seizures can cause mood symptoms, irritability, and even aggression.
Damage to the amygdala can cause a variety of symptoms, most often emotional and behavioral. Individuals may experience irritability, confusion, and a variety of strong emotions. Symptoms of amygdala damage can be complex and may require a combination of treatments.
Oxytocin reduces amygdala activity, increases social interactions and reduces anxiety-like behavior irrespective of NMDAR antagonism.
Acquired amygdala damage reliably impairs fear conditioning, and behavioural, physiological and (in humans and perhaps other species, subjective) responses to threats [6–9].
Lesions in the amygdala have been shown to cause neurological disfunction of ranging severity. Abnormality in the amygdala leads to conditions such as depression, anxiety, autism, and also promotes biochemical and physiological imbalance.
Healing The Brain After Trauma
The good news is that the changes in the brain can be reversed. The amygdala can learn to relax again; the hippocampus can resume proper memory consolidation, and the nervous system can heal to flow between the reactive and restorative modes again.
The cortisol influx caused by depression can cause your amygdala to enlarge, increasing its activity. Since it helps control your emotions, damage to your amygdala can throw your emotions off balance.
Studies in humans have confirmed the key role of the amygdala in fear conditioning as well as in various forms of psychopathological behavior [13].
These local effects within the amygdala are likely to lead to an over-active fear and anxiety related circuit and to decrease the ability of other areas involved in fear inhibition, e.g. hippocampus and medial prefrontal cortex, to dampen amygdala output.
The amygdala is involved in pleasureful emotional learning as well as fearful emotional learning.
Signs and symptoms of amygdala hijack include a racing heartbeat, sweaty palms, and the inability to think clearly. People can try to prevent amygdala hijack by becoming more aware of how they respond to stress.
One way to reliably test the amygdala for its function and role in neural circuits is to use Optogenetics. Optogenetics works by using light to stimulate neurons that have been genetically encoded to express light sensitive ion channels.
The amygdala is not just crucial for regulating our fear response but also for a wide range of other mental processes. Thus, amygdala damage can result in significant issues, such as impaired decision-making and emotional memories.
In line with this, preclinical studies have shown that serotonin has an inhibitory effect on amygdala function. Clinical studies have also demonstrated that effective antidepressant treatment is associated with decreased resting amygdala metabolism33 and decreased amygdala response to emotionally valenced material.
In conclusion, data are consistent with the hypothesis that for those who respond, SSRIs normalize amygdala reactivity during emotional processing of self-referential stimuli.
You can become afraid of your own mind, and that will in and of itself trigger a fight or flight response and anxiety. The amygdala initiates the brain processes that create both fear and anxiety. It has long been known that animals without amygdala do not make fear responses.
Hypervigilance is when the amygdala is caught in the loop of perceiving a threat to life and responding to it. As with the vagus nerve, we can use massage, slow breathing, and yoga practice to reset the system.
1 – Regular mindfulness meditation:
She says: “Our results suggest that meditation can produce experience-based structural alterations in the brain. They found that as little as eight weeks of consistent mindfulness practice is enough to tame and shrink your amygdala.
People with higher pain levels often experience heightened fight-or-flight responses, which throws the nervous system off-balance. Things like stress, pain, and lack of sleep trigger these responses. When we're stuck in fight-or-flight mode, our automatic functions stop working properly.
Studies have shown that larger amygdala volumes are associated with behavioral disorders. Prenatal maternal depression is associated with structural changes in the amygdala, which in turn, is predictive of an increase in behavioral problems. Girls may be particularly vulnerable.