Fixing problems under the surface

Laura Walton takes psychology underwater.

29 August 2019

During one scuba dive as part of my advanced course, I was required to use a compass to navigate a square route underwater (at about 10 metres deep). The task was to swim a specified length by counting fin kicks, then turn 90 degrees and swim the same length again, and turn 90 degrees... until returning to the starting point. I found it a difficult concept to grasp; it was the only dive I was not looking forward to.

The instructor gave me the signal and I set off. I was using rented equipment and the fins had started to rub on my big toe. I couldn’t focus… the pain became all I could think about, I became overwhelmed by the thought that my toenail was being ripped off. I indicated to my instructor that something was wrong with my foot. I’m not sure what I expected, but I know I was looking for some sort of get-out.

He assumed I had cramp, and responded supportively by stretching out my foot and rubbing the back of my calf. I indicated that the problem was much worse and pointed to my toes. He was puzzled, but attempted to assist by taking off my fin. This meant that I could feel the toe with my hands, and I realised that there was actually very little wrong.

My instructor’s attitude to fixing the problem made it very clear to me that he expected we address the issue right there, underwater. Unless I wanted to specifically request an end to the dive, there was no escaping this task by heading for the surface. We put the fin back on, and I set off. I had learned a fundamental lesson in scuba diving: we face the problem under the surface.

The physical and physiological
To understand the psychology of scuba diving, we also need to understand the physical and physiological aspects. Water is heavy. The weight of the water above a diver increases as they descend, so the deeper we go, the more pressure. The weight of the water compresses the gas we breathe. So, when we breathe gas under pressure, it moves around our bodies at a higher density than usual. If we bolt for the surface or come up too quickly, this can have a catastrophic effect on our biological systems. If we have been under for a while, nitrogen has gathered in all our tissues and organs and we are pressurised. Coming up too quickly is a bit like shaking a can of coke then opening it! The bubbles grow, and they cause problems. The worst case scenario is bubbles of nitrogen expanding in the nervous system, in the brain and spinal cord, leading to stroke or permanent paralysis. Also, if a diver holds their breath when ascending, this can cause air to become trapped in the lungs; it expands and can rupture the tissues of the lungs. One potential consequence of this is air migrating to the brain and causing an embolism.

This all means that fleeing to the surface when a problem crops up is simply not an option: you need to learn to deal with it then and there. Perhaps this may mean a decision to end the dive, in a controlled manner; not a sudden exit, but a rational decision supported by effective emotional regulation. As a general rule, the more advanced the diving the slower the rate of return to the surface. For a recreational scuba diver, taking fun dives to 18-30 metres, it is possible to return to the surface within minutes. When Ahmed Gabr set the record for the deepest scuba dive – 332.35 metres in Dahab, Egypt – it took him 12 minutes to dive to that depth, and 14 hours to come back up! There are also commercial divers tasked with completing work such as maintenance to underwater pipelines or oil rigs. These ‘saturation divers’ stay down so long that their bodies become saturated with inert gases like nitrogen. They descend in teams in a type of diving bell, and stay down for days. These operations are carefully planned and managed by surface support.

Going under
Whether on recreational, technical or commercial dives, all divers encounter problems. Within such an extreme environment, human processes can be amplified. A minor stressor can trigger full-blown panic if the diver cannot see a way to address the issue. Responses are often dependent on communication, and miscommunication is common if you are talking to each other in hand signals. So, a huge part of how these problems are faced is behavioural and social: the human factors. For example, the person’s ability to self-regulate under stress, to calm themselves and retain rational thinking ability. If the limbic system of the brain takes over and disconnects from the pre-frontal cortex, the person is in trouble, because the human brain in an underwater crisis will make drastic attempts to reach the surface. A human in panic loses awareness that the equipment in their mouth is supplying them with air and the mask on their face allows them to see. A panicked diver will frequently pull out the regulator and rip off their mask, in an instinctive response to access more air. Alternatively they may enter ‘passive panic’, the divers’ term for a state of dissociation in which the person is shut-down and disconnected. Surrounded by water, neither of these states are helpful. Therefore, basic psychological skills for emotion regulation and management of thoughts are essential in scuba diving.

Psychologists need to go under the surface because the application of research, theory and practice to scuba diving can make a difference. It can improve communication, awareness and optimise performance. Psychological theory can be applied in training programmes to produce effective learning. Ultimately it can make diving safer. Psychologists have already informed the diving community about cognition, perception and memory underwater (and we have also learned about those processes from divers, for example Alan Baddeley’s work on the importance of context on learning). Yet, ‘dive psychology’, as a discipline, is very much in its infancy. A recent literature review by Dorota Niewiedzal and colleagues across four Polish educational institutions, concluded that there is a lack of knowledge about the effect of personality and social functioning, mental health and psychoeducation in relation to human divers.

But interest in this area is growing, and there are several examples of behavioural science being taken underwater: in sports psychology, clinical psychology and human factors. Examples are beginning to emerge across the scuba diving spectrum and from a range of behavioural science disciplines.

Human factors
Technical diving is a specialist area of scuba diving in which people go deeper and longer on their dives. It requires additional equipment and gas supply. The pressure of breathing at depth means that using ordinary air is not advisable. Air contains oxygen, nitrogen and carbon dioxide. Oxygen becomes toxic to humans at around 50-60 metres deep. This can cause seizures of the nervous system, convulsions, unconsciousness and subsequent drowning.

In addition to this sobering effect, the density of the gases breathed has an effect on the diver’s nervous system, in a phenomenon known as ‘gas narcosis’. The diver becomes temporally intoxicated, an experience similar to consuming alcohol. They may become confused, disorientated, anxious, paranoid or even euphoric. This may lead to dangerous actions. For these reasons, those who dive beyond 40 metres or so will use different mixtures of gas to breathe: combinations of gases that are better suited to life at depth.

The complexity of technical diving means that there are often multiple systems operating to execute a dive, for example, the gases need to be mixed properly and labelled accurately, computer software is used to plan the dive and teams of humans work together to follow that plan. Higher complexity of systems introduces more opportunities for problems to occur, and in most cases these problems arise from human error. No diver wants to deal with the consequences of mistakes underwater. Yet, as humans, we are subject to cognitive biases that prevent us from taking effective action. The behaviour of an individual is shaped by the context of the system, so how do we create systems that increase safety and effectiveness?

All industries that employ humans in systems face this issue, and the aviation industry in particular has demonstrated success in the application of human factors. Gareth Lock is a retired Royal Air Force senior officer Navigator of 25 years, who was both a senior supervisor and a tactical flight instructor. Noticing the relevance of human factors to diving, he undertook doctoral research examining the role of human factors in scuba diving accidents. He now offers Human Factors Skills in Diving: high performance development programmes to improve the knowledge, skills and safety of all divers.

In diving, like in aviation, mistakes are often attributed to ‘human error’. But this is not a useful causal explanation; rather it is an outcome of a series of events which were influenced by known human factors such as cognitive bias and social influences on behaviour. Lock’s ‘Human Diver’ training puts teams of divers into a situation that will bring out these human factors, by placing them under stress. For safety reasons, it is not sensible to needlessly increase stress in any extreme environment, certainly not underwater. So, the training, inspired by flight simulators, is a mission to be completed by team within a simulated computer programme. The programme simulates the occurrence of stressors that lead to task loading and loss of situational awareness, and puts pressure on cognitive processes and communication. After the mission, structured and reflective debriefs elicit insights into factors such as individual trigger points, core beliefs, personality traits and habitual responses. For individual divers this gives perspective on why divers make mistakes and how they themselves can adopt procedures to reduce risk of incidents. On a wider level, Lock is working to change culture, procedures and attitudes within the industry.

Sports psychology and performance
Changing systems and improving diver awareness of human factors may be useful, but we can also consider how psychology can support improvements in individual human performance.

In cave diving, scuba divers are both underwater and underground – a direct escape is impossible. Therefore cave divers require superior skills in self-regulation. The diver's air supply is carefully calculated to be sufficient to perform the dive, with a reasonable reserve to use in an emergency. The diver must ensure they leave the cave and return to the surface while they still have air to breathe. This fact can act as a potent psychological stressor, yet the diver needs to find a way to deal with that. If they allow themselves to react to stress, the physiological reactions serve to increase heart rate and, importantly, rate of breathing, and therefore deplete the supply more quickly. This is also the case on deep technical dives, but the presence of a barrier of rock between the diver and the surface has a subtly different effect than when the barrier is a depth of water which must be ascended through slowly.

One common stressor is the loss of visibility due to silt being stirred up in the water. If the diver becomes distressed by this, the changes in breathing may cause them to make movements that agitate the silt even further. Increasing physiological arousal could lead to poor awareness and faulty decision making, leading to errors and exacerbation of the problem. It’s one thing to be unable to see through silt, but the situation becomes a lot worse if the diver’s awareness becomes foggy too. Furthermore, the task requirements of navigation and the laying of lines and markers mean that there are cognitive challenges faced by the diver. Cave divers tend to operate in teams, and therefore those tasks are completed by people working together. There is potential for miscommunication to lead to errors which may have disastrous consequences.

Technical diving, whether on shipwrecks or in caves is a high performance activity. Matt Jevon is a technical diving instructor and Sport Psychologist. One of the few psychologists to work directly underwater, he trains people in technical diving techniques, and also in applying psychological theory to optimise performance. During formal diving courses he includes psychological skills for diving, for example, techniques for retaining situational awareness using pre-learned processes, effective regulation of emotion and applications of procedures for communication to minimise errors. Jevon is quick to stress that the role of a sports psychologist is in training and preparation before the activity, i.e. ‘you don’t interrupt the game’. Skills are taught in advance of the dive and the most intervention during performance would be a cue to connect to those skills.

To illustrate how psychology is applied under the surface, Jevon gave me an example of a training dive with three divers in the team going into a cave system. Jevon was at the front, leading the group into a cave, following him, another experienced diver, and at the back the diver in training. The plan was that Jevon, as the instructor, would lead the dive on the outward journey, then the order of the team would reverse and the diver in training would lead the return to the exit. However, on the journey into the cave the diver in training stopped still. There were no obvious stressors, and it was not apparent what had caused the diver to stop. Jevon used his torch to signal a question: ‘are you okay?’. The diver made little response, vaguely moved their torch but gave no clear signal. The diver was conscious, but apparently disconnected. Jevon gave two further signals to remind the diver to attend to situational awareness, and emotional regulation. These were simple, hand signal cues linked to procedures that the diver had been taught before the dive. The diver regained composure, engaged in communication and continued the dive as planned.

This may not appear a particularly dramatic example, but consider that it may have been the ability of the diver to perform specific psychological skills and the reminder given that led to this safe conclusion. When a diver disconnects, loses awareness and is unable to communicate with the rest of the team, there is potential for sudden deterioration of the dive. In this case, it was vital that the diver remained in control of their actions in order for the group to return to the exit. Had the diver become stressed by perceived problems, then their behaviour may become a risk for everyone in the cave.

Clinical Psychology
Diving is not all about extremes: for most scuba divers it is an enjoyable and relaxing activity. Recreational diving is the term used for people scuba diving for fun. The need to focus on certain skills and the tendency to become enthralled by the underwater world means that divers tend to leave their worries on the surface.

Yet even in recreational scuba there are many issues that psychology can be useful for. People often hold specific fears about depth, sea creatures or open spaces. Anxieties can develop around particular skills. These issues develop in much the same way as any surface phobia or anxiety, and can potentially be resolved with the application of evidence-based techniques, such as graded exposure and response prevention. As a scuba diving instructor, my awareness of psychological processes has been useful, particularly in training new divers. I recall one beginner diver course where a student was overwhelmed by the experience of breathing underwater for the first time. We were in a swimming pool, about a metre deep. He had grown up in and around water, could swim and dive holding his breath, but the sensation of breathing underwater was creating such a strong reaction that he could not remain underwater. We stepped out from the rest of the group and I investigated the issue. He was not frightened, and could understand that breathing was possible, but could not seem to stop himself from coming up. His brain simply could not process breathing underwater. I broke the skill down into simpler steps, starting with breathing with only his face in the water, while standing up. I had him work through each step until comfortable enough to work to the next. At one point he was descending, swimming for a few seconds, coming up saying it was okay, then going back down again. I could see that he was inadvertently creating a behaviour sequence that could easily trap him: by learning that in order to feel safe he needed to keep returning to the surface. So I simply instructed him to swim under water, breathing normally, notice when he felt okay, but then to continue to swim around for several minutes and come up only when feeling calmer than he had been initially. This worked well, and his brain began to habituate to the new sensations. He rejoined the group and began learning more skills. This could so easily have ended up with a person frustrated and unable to understand why they could not keep up with the group. In fact, this social aspect can be especially problematic in diver training, with fear of failure, social judgement and rejection being easily raised.

Another important issue in diving is panic. Even for recreational divers, seemingly small issues can appear insurmountable when they occur underwater. For example, water can leak into a diving mask, it is easily cleared if the diver is competent in that skill, but if the diver is unable to clear the water they may become distressed. With water around their nose they may inhale a little and experience unpleasant sensations. This stress increases emotional and physical reactions and, as they become more stressed, the less capable they become of fixing the problem. Their ineffective actions confirm the threatening nature of the situation and the diver enters a positive feedback loop of escalating panic. In an analysis of snorkelling and scuba diving deaths in New Zealand between 1980 and 2000, led by Michael Davis, panic was a factor in 68 per cent of accidents in scuba diving where the diver’s state was noted.

Yet there is little discussion of preventing panic. In clinical psychology, there are theories to understand stress, anxiety and panic, and approaches to educate people and help them to regain control of their actions in coping with panic. Frequently, when divers panic, the explanations are short: either (1) blame the equipment or (2) blame the diver. In fact, scuba equipment rarely fails, but the shame and embarrassment of losing control of behaviour and a memory of an event impaired by stress makes this an obvious explanation. When divers panic, other divers may say it was the person – ‘they shouldn’t have panicked’ – perhaps referring to personal qualities or lack of skills. The formulation process can help to develop a more complete explanation that is more likely to indicate potential solutions. Theoretical models of stress and panic may also be useful in helping divers to understand this behavioural and physiological phenomenon. I recently published on the ‘panic triangle’, describing panic as sparked only when three elements are present: a deficit in diver readiness, a difficulty in emotional regulation and a stressor. This model may be useful in encouraging divers to stay within the limits of their competence and develop the necessary skills for the dives they are undertaking in order to reduce the risk of panic.

Bringing it back to the surface
Interestingly, whether issues have basis in survival or social fears, it all seems to be intensified in scuba diving. It appears as if the extreme environment brings aspects of the psyche into focus, and certainly there is clear and direct feedback. For example, underwater it is possible to see stress! If a diver breathes fast they produce more bubbles than a relaxed diver. If their breathing is erratic, their ability to control their position in the water is compromised, so they may bounce up and down and flail their limbs. In so many ways, psychological processes have a direct impact on the diver. This creates possibilities, sometimes bringing to life psychological issues that were hidden under a metaphorical surface become all too visible under the surface of the water. They become tangible. They can be worked with.

Divers will often remark on how learning to dive has changed their lives. Whether by improving confidence through challenge, or facing issues that were previously avoided, what we learn under the water can be brought back to the surface.

Laura Walton is a Clinical Psychologist and a qualified scuba instructor
[email protected]

This article is part of our 'Under…' special.

Key sources
Laura Walton
Gareth Lock

Niewiedział, D., Kolańska, M., Dąbrowiecki, Z. et al. (2018). Psychological Aspects of Diving in Selected Theoretical and Research Perspectives. Polish Hyperbaric Research 62(1), 43–54.
Walton, L. (2018). The panic triangle: onset of panic in scuba divers. Undersea and hyperbaric medicine, 45(5), 505-509.
Jevon, M. South-West Technical Diving,