On the inside, the human brain is organised into three main functional areas: the brainstem at the base; the limbic system in the middle; and the cerebral hemispheres at the top.

      The thinking system is primed for potential. Once we’re safe from the dog, we can think about how to avoid crossing its path in future – maybe we need to buy an even bigger dog ourselves! This system allows us to solve problems, set goals, learn and adapt. Because it’s linked more to thinking and rational analysis, it has been described as ‘the cool system’. I call this system BLUE.

      Red

      The RED system is strongly connected to our body through powerful nerves, to maintain the overall functioning of our body and main organs within certain, comfortable limits, and to allow us either to run away or to defend ourselves when the situation demands.

      There are two RED brain abilities that are particularly relevant to performance under pressure:

      1. Emotional regulation

      The RED system runs essential physiological processes like sleep, hunger, thirst, sex drive and our heart and lung function. We don’t want to think much in most of those situations, so the RED system runs our internal world automatically and unconsciously by monitoring sensory information from our main organs. And we can’t switch it off – it never sleeps, even when we do.

      Our RED brain is also constantly monitoring emotional information from our external world. It processes multiple information channels simultaneously to keep pace with cues in our social and emotional environment. The RED system regulates (controls) our emotions, and since our emotional self-control directs our behaviour at all times, the RED system sits at the forefront of how we experience the world around us.

      Our RED brain specialises in processing social and emotional information in a non-linear, holistic way. To give us vital split-second reactions, it runs on broad images, impressions and feelings, delivering an unending stream of moment-to-moment, gut-based judgments about our constantly changing world.

      The trade-off is that a lot of detail is lost or not processed, resulting in an approximate system that provides rapid judgments at the expense of accuracy. Information is combined to provide an overall synthesis of a situation, rather than being broken down into smaller categories.

      To understand this, let’s look more closely at the role of the limbic system in regulating our emotions.

      The limbic system adjusts our emotional state in two main ways: by regulating our level of arousal, and by controlling whether this feels good or bad. It’s like an extremely powerful internal thermostat, turning our energy level and emotional temperature up and down in an instant.

      Nothing is more important to our day-to-day functioning than emotional regulation because it helps keep our body functioning within certain comfortable parameters, where we operate most efficiently. This maintenance of our physical and mental state within a relatively comfortable mid-range or zone is called homeostasis, an essential process for all living organisms. (We will see that understanding – and overcoming – this powerful force to stay comfortable can unlock our performance under pressure.)

      2. Fight–flight–freeze

      Life would be straightforward if we were able to function in comfortable conditions all the time. But we know that in our evolutionary past, we faced deadly threats and had to be constantly on our guard. Think of it in terms of a predator and its prey: the prey either has to react aggressively to deter the predator, or has to get away from the situation in a hurry. We saw this same response earlier in the person confronted by the ferocious dog.

      Our RED system has evolved not just to keep us within a comfortable physiological window when conditions are safe and allow it, but also to keep us alive when we face significant threat. It does this through the fight, flight and freeze reactions, which are our stress reactions. Within a split second, our brain and body are ready either to flee from the threat, or to fight it off.

      Our two amygdalae, considered the most primitive parts of the limbic system, act as our threat detectors. They’re constantly on high alert and exquisitely sensitive: they can be triggered simply by picking up on the dilation of another person’s pupils, a sign of potential hyper-vigilance or fear. They can respond unconsciously within 30 milliseconds, much faster than the 250 to 500 milliseconds it takes us to consciously focus attention with our BLUE brain. This is why we can find ourselves reacting to something without knowing why; then our conscious BLUE mind will catch up and recognise the threat that our RED system saw a quarter to half a second beforehand. In life-threatening situations, our amygdalae allow us to act first and think later.

      If we can’t overcome or get away from our opponent, we feel trapped, and a more primitive reaction can kick in: freeze. This reaction has a slightly different biological pathway from the fight–flight mechanism, and it works in the opposite way: it shuts us down physically. It’s a last-ditch response to danger, when horror kicks in. In the animal world, this is where caught prey plays dead, hoping the predator will lose interest and enable it to escape. In the human world, we look blank and stare. Freeze starts out with a spike of arousal, but then transforms into a profoundly low-arousal state.

      Psychologically, we disconnect from our body. If we can’t get out of there physically, we certainly don’t want to be present mentally. We go numb as endorphins are released to protect us from physical and mental pain. The technical term for this is dissociation, a mechanism that has fascinated psychologists for over 200 years.

      Sometimes dissociation even involves a loss of muscle tone, leading us to fold or collapse – a bit like when a team of defeated players fall to the ground at the final whistle, when just moments before they were desperately trying to turn things around.

      The autonomic nervous system

      A well-organised RED limbic system will ensure that we are emotionally stable, flexible and resilient. It will allow us to fine-tune our physical and mental state when we are safe, react quickly to defend ourselves when we are under threat, and settle efficiently once the threat has gone.

      It makes these adjustments using the autonomic nervous system (ANS), which, as the name suggests, functions automatically. It’s a RED system based on feeling, so we don’t have to think to turn it on.

      The autonomic system has two main branches: the sympathetic branch and the parasympathetic branch. We now know that there are in fact two parasympathetic branches, both related to the large vagus nerves, which run from our brainstem at the base of our skull upward to our facial area, and downward to organs in our chest and abdomen. The two parasympathetic pathways are called the ventral vagal and dorsal vagal pathways. (Ventral means ‘front’ and dorsal means ‘back’, reflecting their relative positions within the nerve.)

      The bottom line is that to properly understand how our fight, flight and freeze reactions work – and therefore what’s happening when