The Science | Safe and Sound Protocol UK

The Science Behind the SSP

The Autonomic Nervous System (ANS)

The autonomic nervous system (ANS) plays a vital role in regulating various bodily functions, including heart rate, blood pressure, respiratory rate, digestion, metabolism, and other processes that occur automatically and unconsciously. The ANS consists of two main branches with opposing functions: the sympathetic (“fight or flight”) nervous system and the parasympathetic (“rest and digest”) nervous system. The two branches work together to maintain homeostasis and ensure the body’s survival by responding to different environmental and internal stimuli. The balance between these two branches is crucial for adapting to various situations and for promoting overall wellbeing.

Polyvagal Theory

Polyvagal Theory, proposed by Dr. Stephen Porges explains the role of the vagus nerve in regulating the autonomic nervous system and its impact on social behaviour and emotional regulation. The theory suggests that the vagus nerve has evolved over time, leading to a hierarchical organisation with three distinct branches, each associated with different adaptive responses. The ventral vagal branch, developed the most recently in our evolution, supports social engagement and connection, promoting feelings of safety and well-being. The sympathetic branch prepares the body for fight or flight responses. The dorsal vagal branch, on the other hand, is linked to immobilisation and shutdown (freeze) responses, marking a more primitive and defensive reaction to perceived threats. The Polyvagal Theory highlights how the autonomic nervous system influences our physiological and emotional states, impacting our ability to engage with others and navigate social interactions.

When faced with what the body perceives as danger, it responds by retuning the nervous system into one of the states of defence – fight, flight or freeze. In today’s busy and uncertain world, many of us are stuck in a chronic defensive state of stress, which impacts on how we think and feel and on how we connect with others, adversely affecting our health and day to day experience in the world.

Where does the SSP come in?

The SSP is a non-invasive application of Polyvagal Theory, based on decades of research. The SSP applies a bottom-up approach to help people regulate their nervous system more consistently, which can result in life-changing benefits: you may feel calmer, safer, more grounded and resilient, and less irritable, anxious and overwhelmed.

Listening is connected to the vagus nerve, the body’s internal control centre for processing and responding to cues and signals from the world around us. The SSP uses specially filtered music to train the neural network associated with listening to focus on the frequency range of the human voice to stimulate the vagus nerve. As you learn to focus on the sound frequencies of human speech through the SSP, the vagus nerve becomes stimulated, and the state of feeling safe and calm becomes more accessible.