The Invisible Lion Glossary

Explanation of Terms Used Within the Book


1. Acceleration

The speeding up of the nervous system in response to threat. If you see a lion running towards you, for example, your nervous system will accelerate, so that you can deal with the problem as quickly as possible. (See 16)

2. Attachment Style

These are learned ways of behaviour in relationships that come from imitating the over-reactive, under-reactive, or just right (Goldilocks) nervous systems of our caregivers. (See 11, 14, 19)

Attachment style stems from research done on attachment theory carried out by psychologist John Bowlby, who worked as a psychiatrist in London, treating emotionally disturbed children. His work led him to consider the impact that a child’s relationship with his or her mother had on their social, emotional, and cognitive development. He found that the impact was significant, and that separation from the mother caused great distress in babies.

Bowlby defined attachment as a ‘lasting psychological connectedness between human beings.’[1] He also suggested that attachment can be considered in an evolutionary context, in that the caregiver provides safety and security to the infant.[2]

[1] Schaffer, H. R., & Emerson, P. E. (1964). The development of social attachments in infancy. Monographs of the Society for Research in Child Development, 1-77.

[2] McLeod, S. A. (2017, Feb 05). Attachment theory. Simply psychology:

3. Baggage

Baggage is the accumulation of unfinished business that we carry in our nervous system. If you haven’t finished dealing with a previous threat, it becomes baggage, and like the name suggests, you carry it around with you. Baggage can come from any adverse experiences which overwhelmed us and which we therefore have not yet finished reacting to. (See 18)


4. Boundaries

Boundaries are protective measures that we can take to reduce the impact of a trigger. These are measures we put in place ourselves, like distancing from a person who triggers us, or asking for things to be done differently. Boundaries are not anyone else’s responsibility. If someone’s behaviour triggers me, I can implement a boundary by distancing myself from the person or changing my behaviour. (See 17)

5. Charge

Activation in the nervous system in response to threat. (See 1)

6. Containment

A way of moderating disproportionate reactions by reducing the output of energy from our baggage in our reactions. This is a reduced reaction, not a complete shut down and aims to become appropriate to the current threat, not a reaction to all our historic unfinished business. This helps us to act appropriately when someone or something triggers us, so that we can feel what it might be like to behave as if we have no baggage at all. (See 15)


7. Discharge

The release of energy from the nervous system after freezing and then unfreezing while responding to a threat. A gazelle who was immobilised but then has managed to escape from a lion, for example, will discharge their frozen flight and fight energy after the danger has passed, and return to their normal behaviour. (See 16)

8. Dysregulation

A breakdown in normal functioning of the nervous system, resulting in a reduced capacity to react appropriately to real or perceived threats. Instead of a gradual response to escalating threat, a dysregulated nervous system typically is very activated (anxious) or very shut-down (depressed) with not much useful in between.(See 16)

9. Fight or Flight

The fight or flight response to a threat is one that involves an active response, either fighting very strongly or running very fast (depending on which is more likely to result in safety). (See 16)


10. Freeze

The freeze response to threat is a passive response, during which the body can appear to be paralysed. In animals this can be a literal freezing of the whole body, but in humans it can be more complicated, such as going to a different place in the mind, such as dissociation. Freeze happens when fighting and fleeing don’t work and the threat is still there. (See 16)

Much research on fight/flight/freeze has been carried out by Dr. Peter Levine. All animals are programmed by evolution to flee, fight, or freeze in the face of great threats to their survival. In humans, when these natural responses to danger are thwarted and people are helpless to prevent dangers to their survival, like in cases of a car accident or physical beating, the unfinished defensive actions become stuck as undischarged energy in their nervous systems. They stay physiologically frozen in an “unfinished” state of extremely high biological readiness to react to the traumatic event, even long after the event has passed. Levine believes that psychological trauma is very much about action interrupted, which the traumatised human brain and body still needs to complete processing. Often, people can experience traumatic events and process them without any long-lasting consequences. The problem occurs when the body and mind is unable to process the event or discharge the energy. The stress response is stuck and un-discharged. Levine explained in his 1997 book ‘Waking The Tiger, that this is ‘an incomplete physiological response suspended in fear.[1]

[1] Levine, P. A., & Frederick, A. (1997). Waking the tiger: Healing trauma - the innate capacity to transform overwhelming experiences. Berkeley, CA: North Atlantic Books,U.S.

11. Goldilocks Response

A response to a stimulus that is in proportion to the threat level of the stimulus itself, instead of an over reaction or under reaction. The term comes from the fairy-tale ‘Goldilocks and The Three Bears’, in which a young girl named Goldilocks stumbles across a home in the forest belonging to a family of bears. She enters the home and sees three bowls of porridge on the table. She tries the first bowl, but it’s too hot. She tries the second bowl, but it’s too cold. Finally, she tries the third bowl, which is just right.

12. Homeostasis

A return to normal level of a biological system after a change. In relation to the nervous system, this is when the nervous system returns to a calm state unaffected by threat, after being activated or charged by a threat. What goes up, must come down.


13. Limbic System

The limbic system is a set of structures in the brain that controls emotion, memories and arousal. It detects fear and threat, controls bodily functions and perceives sensory information (See mammalian brain).

14. Nervous System

A physical part of the body that includes the brain, spinal cord, nerves, and sensory organs. The nervous system receives, interprets, and responds to stimuli from inside and outside the body. It is the nervous system both picks up on threats in the environment via the sensory organs, and carries signals from the brain to the body to take action.

15. Neuroception

The term ‘neuroception’, coined by Dr. Stephen Porges, describes how the whole body distinguishes whether situations or people are safe, dangerous, or life threatening. It concerns how the body and our senses are reading our environment. It is the body’s perception of our situation, mediated by the nervous system, hence the term ‘neuro-ception’.

Through the process of neuroception, we experience the world in a way in which we are involuntarily scanning situations and people to determine if they are safe or dangerous.[1]

[1] Clarke, J., 2019. Polyvagal Theory And How It Relates To Social Cues. [online] Verywell Mind. Available at: <> [Accessed 23 March 2020].


16. Overwhelm

The breaking point in the nervous system when the charge is too much for the system to handle. There is a limit to how charged the nervous system can become in response to threat. When a threat response causes the nervous system to reach that point, it freezes and the energy is stored in the body until it gets a chance to be released again via discharge. (See 5, 16)

17. Overreaction

A response to a stimulus or trigger that is of greater intensity than the intensity of the stimulus itself. If someone tells me that a picture I drew is bad, and I yell at them for saying so as if my life is in danger, that is an example of an over-reaction. (See 17)

18. Reptile Brain, Mammal Brain, Human Brain

There are three main ‘parts’ of the brain that govern our nervous systems. These parts have developed over our evolution as a species. This ‘three part’ model of the brain was developed by American physician and neuroscientist Paul McLean in the 1960's.

These three parts of the brain are not in agreement, but also do not operate independently of one another. They instead function interdependently.

The reptilian brain, the oldest of the three brains and governs vital bodily functions such as our heart rate, breathing, body temperature and balance.[1]

The mammalian (or limbic) brain emerged in the first mammals. It is responsible for emotions in human beings. The main structures of the limbic brain are the hippocampus, the amygdala, and the hypothalamus. The limbic brain is the seat of the value judgments that we make, often unconsciously, that have an influence on our behaviour.[2]

The human brain (or neocortex) first assumed importance in primates and is considered to be the logical, thinking part of the brain. This part of the brain played a role in the development of human language, abstract thought, imagination, and consciousness.[3]

[1] n.d. The Brain From Top To Bottom. [online] Available at: <> [Accessed 23 March 2020].

[2] ibid.

[3] n.d. The Brain From Top To Bottom. [online] Available at: <> [Accessed 23 March 2020].


19. Social Engagement

A way of reducing and preventing threats by creating bonds and connection with others. When a potential threat to our survival is another person or other people, we can create social bonds and connections to help us feel safe and secure. (See 16)

20. Threat

Anything that poses a danger to your survival. This can be real or just perceived. It can be external or internal.

21. Threat Response Cycle/Social Engagement System

The threat response cycle describes the process by which we orient to our environment when we become aware of a potential threat. It involves freeze, fight or flight, vigilance, and social engagement. This is the hierarchy of responses to the threat.


22. Trigger

Anything that stimulates a threat response, usually an echo of an earlier experience which you have not finished reacting to yet. Triggers are very personal - different things trigger different people.  If you were bitten by a dog when you were younger, for example, and didn’t deal discharge your body’s response to that fully when it happened, the experience may be stored in your body. If you hear a dog barking at a later stage, this might trigger you to go back to those unfinished responses, such as fear or flight.

23. Unfinished Business

Baggage. Energy stored in the nervous system that has not been discharged. The energy stays in the system until it is activated again. This happens as a result of a traumatic or frightening experience, duirng which the body’s active threat response was frozen, and then did not fully unfreeze. So it didn’t fully deal with the situation at the time, instead stored the active energy of the reaction to be dealt with later. (See 7)

24. Under-reaction

A response to a stimulus that is significantly less intense than the intensity of level of the stimulus itself. If I yell at you for something you didn’t do, and you respond timidly or not at all, then you are under reacting.


25. Vigilance

Awareness of a potential threat in the environment. In a state of vigilance, all of the senses are heightened to be able to pick up on external threats more quickly and easily.(See 16)

26. Well-regulated Nervous System

A nervous system that responds appropriately to threat. Not too strongly, or too weak, but appropriate to the given situation. This can be learned from the caregiver-baby relationship, or we can teach it to ourselves using boundaries and containment.


©2019 by Benjamin Fry