the science behind anxiety and stressGiving a patient or client the tools to trigger the body’s natural relaxation response can make an immediate and positive difference to improving physical and mental health. Jan Alcoe explores how two vital parts of the nervous system work in response to anxiety and stress.

The human brain is hard-wired for survival. 

The amygdala is part of the limbic system (the ‘emotional brain’) and is involved in many of our emotions and motivations, particularly those that are related to survival. Picture this as a burglar alarm in your house. While you are sleeping soundly, it constantly scans your environment for signs of danger, based on the sensory memories of your past experiences. If it recognises a threatening sound – a loud crash, sight – a looming shadow, sensation – crawling on the skin, or other sign of danger, it will activate. This will occur before you have had time to investigate whether a burglar has broken in or an overnight guest has decided to go downstairs for a drink of water!

When the alarm is activated, powerful hormones, including adrenaline, are released throughout the body, prompting a whole host of physiological changes to enable you to either fight or flee the danger. At this point, you may notice your heart palpitating, your body shaking and sweating and your breath coming in gasps, because your whole body has been mobilised for action. The survival mechanism is firmly based on ‘live first and ask questions later’!

The stress response

Unfortunately, the stress response can ‘kick off’ in a whole range of situations which we associate with fear but which are not, in themselves, life-threatening, for example;

- being faced with unreasonable work demands
- giving a public performance
- going into a hospital,
- or even when we just imagine ourselves in uncomfortable situations.

The effects of such anxieties may impair our ability to control our body, for example, when we find ourselves shaking and sweating as we walk onto the stage to give a public talk.

Feeling stressed also means that we are more prey to our emotions, which operate from a ‘threat or no-threat’, ‘good or bad’ perspective. As your temperature rises, the emotional brain hijacks the higher neocortex (the ‘thinking brain’) which normally provides a more intelligent analysis of what is happening, following the initial danger trigger. Consequently, we find ourselves unable to think clearly, keep things in perspective and make good judgments. For example, we may feel threatened in a meeting, and as our level of upset or anger increases, we are unable to make the fine distinctions we need to analyse and calmly influence opinions in the room.

Panic attacks

When we are highly stressed, our anxiety may ‘spill over’ into a full-blown panic attack and we then experience more extreme physiological and mental effects.

If we do not allow our bodies to recover and re-balance, long term stress hormones like cortisol are released. In time, these can negatively affect our health, impairing our immune system, digestion, sleep and sex drive, or paving the way into depression, generalised anxiety or other mental difficulties.

We all need an optimum level of stress to be able to perform effectively when we need to, and sometimes we need the extra emotional arousal to give a big performance. However, being able to ‘switch off’ the fight-or-flight response and ‘switch on’ the body’s relaxation response avoids a build-up of stress hormones and is essential to our well-being – physically, mentally and emotionally. Stress and relaxation are two sides of the same coin, linked as they are to two different branches of the central nervous system, but can’t experience feelings of relaxation and tension at the same time.  


The relaxation response is the “opposite” of the fight-or-flight response, activating the parasympathetic nervous system, rather than the sympathetic nervous system. It can be prompted by calming and deep relaxation techniques. There are untold benefits to practising relaxation on a regular basis. Not only does relaxation allow the body a chance to re-charge and repair, but it calms the mind so that we are more resourceful in how we handle situations, relate to others and make decisions. If you can create one part of this relaxation response, for example, slowing and deepening your breathing, then the chain of other responses will follow.


Jan Alcoe BSSc, DHypPsych(UK), GQHP is a clinical hypnotherapist and author of 49 Ways to Think Yourself Well (Step Beach Press), Lifting Your Spirits: 7 tools for coping with illness and The Heart of Well-being: 7 tools for surviving and thriving (both published by The Janki Foundation for Global Health Care)