|Psychological aspects of SCUBA diving: Journal references & books
Research on the psychological aspects of SCUBA diving has been published in professional journals1 from a variety of fields: psychology, medicine, physiology, sport, tourism and leisure. This makes it challenging to keep current on relevant research. The following is a selected list of journal articles on psychology and SCUBA diving.
||1 Before an article is published in a professional journal it goes through a process whereby it is reviewed by a group of peers - colleagues who have expertise in the content area that is the subject of the article. This is meant to increase the quality and trustworthiness of the information being presented in the article.
Hemelryck W, Germonpré P, Papadopoulou V, Rozloznik M, Balestra C. Long term effects of recreational SCUBA diving on higher cognitive function.
Scandinavian Journal of Medicine & Science in Sports. 2014; 24: 928-934.
Abstract: Study investigated long-term effects of SCUBA diving on cognitive function using a battery of neuro-psychometric tests: the Simple Reaction Time (REA), Symbol Digit Substitution (SDS), Digit Span Backwards (DSB), and Hand-Eye Coordination tests (EYE). A group (n = 44) of experienced SCUBA divers with no history of decompression sickness was compared to non-diving control subjects (n = 37), as well as to professional boxers (n = 24), who are considered at higher risk of long term neurological damage. The REA was significantly shorter in SCUBA divers compared to the control subjects, and also more stable over the time course of the test. In contrast, the number of digits correctly memorized and reordered (DSB) was significantly lower for SCUBA divers com- pared to the control group. The results also showed that boxers performed significantly worse than the control group in three out of four tests (REA, DSB, EYE). While it may be concluded that accident-free SCUBA diving may have some long-term adverse effects on short-term memory, there is however, no evidence of general higher cognitive function deficiency.
Plaza JC, Ruiz EJGF, García JJL, Conde LC. Prediction of human adaptation and performance in underwater environments.
Psicothema, 2014; 26: 336-342.
Abstract: Background: Environmental stressors require the professional diver to undergo a complex process of psychophysiological adaptation in order to overcome the demands of an extreme environment and carry out effective and efficient work under water. The influence of cognitive and personality traits in predicting underwater performance and adaptation has been a common concern for diving psychology, and definitive conclusions have not been reached. Method: In this ex post facto study, psychological and academic data were analyzed from a large sample of personnel participating in scuba diving courses carried out in the Spanish Navy Diving Center. In order to verify the relevance of individual differences in adaptation to a hostile environment, we evaluated the predictive validity of general mental ability and personality traits with regression techniques. Results: The data indicated the existence of psychological variables that can predict the performance (R2 = .30, p<.001) and adaptation (R2N = .51, p<.001) of divers in underwater environment. Conclusions: These findings support the hypothesis that individual differences are related to the probability of successful adaptation and effective performance in professional diving. These results also verify that dispositional traits play a decisive role in diving training and are significant factors in divers' psychological fitness.
Fock AW. Analysis of recreational closed-circuit rebreather deaths 1998-2010.
Diving and Hyperbaric Medicine, 2013; 43:78-85.
Abstract: Introduction: Since the introduction of recreational closed-circuit rebreathers (CCRs) in 1998, there have been many recorded deaths. Rebreather deaths have been quoted to be as high as 1 in 100 users. Methods: Rebreather fatalities between 1998 and 2010 were extracted from the Deeplife rebreather mortality database, and inaccuracies were corrected where known. Rebreather absolute numbers were derived from industry discussions and training agency statistics. Relative numbers and brands were extracted from the Rebreather World website database and a Dutch rebreather survey. Mortality was compared with data from other databases. A fault-tree analysis of rebreathers was compared to that of open-circuit scuba of various configurations. Finally, a risk analysis was applied to the mortality database. Results: The 181 recorded recreational rebreather deaths occurred at about 10 times the rate of deaths amongst open-circuit recreational scuba divers. No particular brand or type of rebreather was over-represented. Closed-circuit rebreathers have a 25-fold increased risk of component failure compared to a manifolded twin-cylinder open-circuit system. This risk can be offset by carrying a redundant 'bailout' system. Two-thirds of fatal dives were associated with a high-risk dive or high-risk behaviour. There are multiple points in the human-machine interface (HMI) during the use of rebreathers that can result in errors that may lead to a fatality. Conclusions: While rebreathers have an intrinsically higher risk of mechanical failure as a result of their complexity, this can be offset by good design incorporating redundancy and by carrying adequate 'bailout' or alternative gas sources for decompression in the event of a failure. Designs that minimize the chances of HMI errors and training that highlights this area may help to minimize fatalities.
Saetrevik B. Developing a context-general self-report approach to measure three-level situation awareness.
International Maritime Health, 2013; 64: 66-71.
Abstract: Background: Situation awareness (SA) is considered to be crucial for work in safety critical organisations, yet its precise definition and an agreed upon measurement approach have yet to emerge. SA is often measured as an operator's overview of some specific parameters within a given work setting and a given time frame, an approach that entails both advantages and disadvantages. The current approach examines whether some aspects of SA relating to workplace safety can also be captured in a context-general inventory. Material and methods: 166 offshore maritime personnel answered the SA inventory with 13 items describing the respondent's typical cognitions concerning safety issues. Results: Confirmatory factor analysis of response patterns showed that the internal pattern among the items reflected the three level structure predicted by the leading theoretical model. Strengths and weaknesses of the inventory itself, as well as the approach in general are discussed, and future research directions are outlined. Conclusions: It appears feasible to measure aspects of SA in a context-general inventory, though additional adjustment and validation is required.
Buzzacott P, Denoble P. The epidemiology of murder and suicide involving scuba diving.
International Maritime Health, 2012; 63: 207-212.
Abstract: Murder and suicide in involving scuba are extremely rare. A systematic search identified 19 published studies describing 4,339 recreational diving fatalities occurring between 1956 and 2011. Case vignettes identified three possible murders and eight likely suicides. These are summarized and the victims' demography described. Prevalences of 69 murders per 100,000 diving fatalities and 184 suicides per 100,000 diving fatalities are lower than found among all cause mortality in the general population of USA and Australia.
Edmonds C. A forensic diving medicine examination of a highly publicised scuba diving fatality.
Diving and Hyperbaric Medicine, 2012; 42: 224-30.
Abstract: A high-profile diving death occurred in 2003 at the site of the wreck of the SS Yongala off the Queensland coast. The victim's buddy, her husband, was accused of her murder and found guilty of manslaughter in an Australian court. A detailed analysis of all the evidence concerning this fatality suggests alternative medical reasons for her death. The value of decompression computers in determining the diving details and of CT scans in clarifying autopsy findings is demonstrated. The victim was medically, physically and psychologically unfit to undertake the fatal dive. She was inexperienced and inadequately supervised. She was over-weighted and exposed for the first time to difficult currents. The analysis of the dive demonstrates how important it is to consider the interaction of all factors and to not make deductions from individual items of information. It also highlights the importance of early liaison between expert divers, technicians, diving clinicians and pathologists, if inappropriate conclusions are to be avoided.
Kler BK, Tribe J. Flourishing through scuba: Understanding the pursuit of dive experiences.
Tourism in Marine Environments, 2012; 8: 19-32.
Abstract: This article presents evidence for a new facet of our understanding of why scuba divers pursue their interest so fervently and are willing to travel to do so. The perennial question of why people travel is addressed through the concept of eudaimonia, the good life, or flourishing, an idea originating with Aristotle but currently enjoying renewed interest in the context of positive psychology and well-being tourism. Results of a qualitative study are presented through themes that resonate with the authentic happiness model used to evaluate long-term satisfaction, happiness, or eudaimonia. Exploratory findings indicate that participants gain meaning and fulfillment from the acts of learning and personal growth, and they are motivated to dive because this special interest promotes positive experiences, which may lead to the good life.
Dimmock K, Wilson E. "Take a deep breath": how recreational scuba divers negotiate in-water constraints.
Leisure, 2011; 35: 283-297.
Abstract: A significant body of work now exists on what constrains people's leisure. While early theorizations of constraints focused on what prevented individuals from participating in leisure, the literature has expanded to include discussions on how constraints may be negotiated, overcome or substituted. This article explores constraints negotiation in the context of adventurous leisure. This study considers how leisure constraints are negotiated in the in-situ experience of recreational scuba diving. In-depth interviews were conducted with 27 recreational divers. Analysis revealed three interrelated negotiation strategies used to deal with in-situ constraints, namely consolidate, co-operate, or cancel. These negotiation techniques were influenced by factors including divers' histories, perceptions of the severity of the constraint and in-water experience. Findings support the recognition of in-situ constraints negotiation in adventurous leisure. Results highlight the need to reflect on how individuals negotiate constraints during leisure, particularly in difficult environments which can present unpredictable and dangerous risks.
Musa G, Seng WT, Thirumoorthi T, Abessi M. The influence of scuba divers' personality, experience, and demographic profile on their underwater behavior
Tourism in Marine Environments, 2010; 7: 1-14.
Abstract: Scuba diving activity is known to cause detrimental impact on the marine environment and its sustainability. This study explores the influence of divers' personality, experience, and demo- graphic profile on their underwater behavior. Data were collected using convenience sampling among divers in Malaysia. A total of 302 questionnaires were returned and analyzed. The results show that divers are generally responsible underwater. Scuba diving experience parameters of duration of involvement, number of dives, self-rating experience, and diving frequency influence underwater behavior. Divers with high neuroticism are more likely to be irresponsible, while high agreeableness personality factor is related to more responsible behavior underwater. Based on the results the authors provide some managerial recommendations in order to promote responsible scuba diving activities.
Petri NM, Stipancevic H, Sutlovic D, Gojanovic MD. Death of a scuba diver caused by vomiting and panic: A case report.
American Journal of Forensic Medicine Pathology. 2010; 31: 1-4.
Abstract: Scuba diving fatalities are rare and sometimes extremely difficult to explain. A thorough forensic investigation, conducted by a qualified team, helps avoid possible later questions and doubts, family concerns and judicial matters, since a significant body of evidence is lost after the body of the victim is buried or the equipment is reused. We report about a death of a scuba diver who was drowned while diving to the depth of 30 meters. Before being assisted to the surface, the diver panicked and removed the regulator from his mouth. The technical expertise of the scuba gear and the chemical analysis of the air from the high-pressure cylinder revealed no irregularities. Homicide, suicide, nitrogen narcosis, oxygen toxicity, and regulator malfunction were ruled out as possible causes of death. The most probable cause that triggered the event was vomiting into the regulator, as confirmed nearly 4 years later by the toxicological analysis of the traces of matter found in the dry chamber of the breathing regulator. Such an analysis should be considered when investigating suspicious diving related deaths and could be undertaken even after a significant time delay if the equipment is kept properly stored.
Straughan ER. Touched by water: The body in scuba diving.
Emotion, Space and Society. 2010; 5:19-26.
Abstract: Focusing on the leisure practice of scuba diving, I examine how 'touch' works as a sense experienced through material engagement with the aquatic world for both physical and metaphorical effect. Technologically facilitated and environmentally positioned, scuba diving brings together the distal and the proximate to produce a particular experience of space and a particular mobilisation of emotion. The paper positions itself within the conceptual context of embodiment in order to consider corporeality in terms of its visceral and material capacities that effect and direct movement, as well as the experience of the sensuous via an engagement with the diving environment. In doing so, it draws upon work within the social sciences that has acknowledged the importance of an embodied engagement with environments that are seen as therapeutic or restorative for their ability to instill a sense of well-being and calm through a re-centering of the self. Drawing out the meditative capacities of scuba diving, the paper considers the aquatic world as, for some divers, a therapeutic landscape.
Dimmock K. CCN: Towards a model of comfort, constraints and negotiation in recreational SCUBA diving.
Tourism in Marine Environments. 2010; 6: 145-160.
Abstract: Scuba diving has become a popular form of marine-based tourism and adventure activity. Yet, little empirical information details what transpires during an encounter once a diver descends from the surface. Using a qualitative methodology, the stories of scuba diving experiences were collected and examined in an effort to define some of the prevailing features of an underwater encounter. The presence of comfort, constraint, and negotiation (CNN) emerged as important features of scuba diving. Titled CCN, this article offers a conceptual model that presents the central concepts and depicts the association between comfort, constraints, and negotiation during scuba diving as dynamic elements of the activity.
Buzzacott P, Rosenberg M, Pikora T. Using a Delphi technique to rank potential causes of scuba diving incidents.
Diving and Hyperbaric Medicine, 2009; 39: 29-32.
Abstract: Scuba diving experts suggested and ranked potential causes of three known risk factors for scuba diving incidents: running out of air, losing buoyancy control and making rapid ascents. Three types of scuba diving expert participated: medical experts, divemasters and expert divers. In three rounds, consensus was reached for 28 (58%) of 48 suggested causes. Inexperience was ranked highly for all three risk factors, as was panic/anxiety/stress and diver failure (to monitor contents of gauge or release air on ascent). Overall, the expert panel suggested potential causes that were more often human or use-of-equipment related, than environmental.
McGeoch G, Davis FM. Analysis of a complex recreational scuba diving accident: French Pass, New Zealand, 2000.
Diving and Hyperbaric Medicine, 2009; 39: 20-28.
Abstract: In March 2000, six students and an instructor dived using open-circuit scuba in a narrow pass and were swept by a strong current to a depth of 90 meters' sea-water. Three died and four were injured, which makes the incident the worst diving accident in New Zealand history. The group was an officially sanctioned course with many factors contributing to the final tragic events. The dive is described and the medical response is examined. The legal consequences are reported and their implications for diver training and employment are discussed.
Dimmock K. Finding comfort in adventure: experiences of recreational SCUBA divers.
Leisure Studies. 2009; 28: 279-295.
Abstract: Adventure experiences are most often examined from a position that seeks to understand interpretations of risk and uncertainty. This paper has adopted an alternate view in seeking to consider aspects of participants' comfort during an adventure-based experience, namely recreational SCUBA diving. Interviews were held with divers who had variation in their level of experience and involvement with the activity. An interpretive approach to analysing the interview data revealed physical, social, psychological and visual contexts of comfort within SCUBA diving. Themes that reflect comfortable experiences are important to recreational SCUBA diving and the broader context of leisure.
Dimmock K, Wilson E. Risking comfort? The impact of in-water constraints on recreational scuba diving.
Annals of Leisure Research. 2009; 12: 173-194.
Abstract: A substantial body of work has considered the role and impact of constraints on the leisure experience. Recent research in leisure constraints theory, however, has moved beyond a preoccupation with barriers to access and identified the importance of in situ constraints and their impact on the leisure experience itself. New directions in constraints research are needed to expand our understanding of in situ constraints in leisure segments like adventure recreation. This paper presents the findings of an interpretive, qualitative study of how in situ (or 'in-water') constraints impacted on the experiences of 27 recreational scuba divers in Australia. The notion of comfort as it applies to adventure leisure and diving is also explored. Using a grounded approach to analysis, it was revealed that divers' comfort was constrained in physical, psychological, social, and visual contexts. This suite of constraints worked to limit, disrupt, or impede divers' in-water comfort, bringing discomfort or uncertainty into a dive. The implications and application of these findings for adventure leisure research and practical management of the scuba dive experience are discussed.
Bonnet A, Fernandez L, Piolat A, Pedinielli JL. Changes in emotional states before and after risk taking in scuba diving.
Journal of Clinical Sport Psychology. 2008; 2: 25-40.
Abstract: The notion of risk-taking implies a cognitive process that determines the level of risk involved in a particular activity or task. This risk appraisal process gives rise to emotional responses, including anxious arousal and changes in mood, which may play a significant role in risk-related decision making. This study examines how emotional responses to the perceived risk of a scuba-diving injury contribute to divers' behavior, as well as the ways that risk taking or non-risk taking behavior, in turn, affects emotional states. The study sample consisted of 131 divers (risk takers and non-risk takers), who either had or had not been in a previous diving accident. Divers' emotional states were assessed immediately prior to diving, as well as immediately following a dive. Results indicated presence of subjective emotional experiences that are specific to whether a risk has been perceived and a risk has been taken. Important differences in emotion regulation were also found between divers who typically take risks and those who do not.
Cater, CI. The life aquatic: Scuba diving and the experiential imperative.
Tourism in Marine Environments. 2008; 5: 233-244.
Abstract: There has been significant growth in the number of qualified scuba divers over the last 30 years, and although estimates are vague, there may be as many as 14 million qualified divers worldwide. Although centered on what may be thought of as primarily a recreational practice, it is also a very strong force for marine tourism. This is compounded by the fact that many active divers live in temperate climes, and prefer to engage in the sport, sometimes exclusively, when visiting tropical regions on holiday. A significant dive tourism industry has therefore emerged to cater for these requirements and has been subject to academic and policy inquiry. However, as this article argues, much of this has been focused on management of impacts without adequate attention on diver motivations, which can considerably inform and assist the former. Consequently this article seeks to examine this activity through the grounded perspectives of scuba divers themselves, in parallel to a categorization of leisure motivation suggested by Beard and Ragheb in 1983. However, the work seeks to note that, in addition to these categories, the scuba diving experience is also profoundly embodied, entailing a wide range of sensations and feelings, many of which may be new to the first-time diver. These are explained through concepts of embodied experience, which is a rich arena for marine tourism research inquiry.
Fernandez I. EMDR After a Critical Incident: Treatment of a Tsunami Survivor With Acute Posttraumatic Stress Disorder.
Journal of EMDR Practice and Research. 2008; 2: 156-159.
Abstract: Research indicates that EMDR is effective for the treatment of posttraumatic stress disorder (PTSD), with numerous studies showing a high percentage of symptom remission after 3 sessions. The case of a survivor of the December 26, 2004 tsunami with acute PTSD is presented. He could no longer work as a diving instructor because of the anxiety he felt at the very thought of diving again, especially with a group. Treatment for overt trauma symptoms was completed within 3 sessions, including all 8 phases and the 3-pronged protocol (i.e., past, present, future tar- gets). One EMDR session was sufficient to process the trauma and alleviate the related symptoms, while another session was necessary for re-evaluation and processing present triggers and future templates. Resource installation was particularly helpful to prepare him for those future situations that had been generating anxiety as a result of his traumatization. Follow-up after one month and one year confirmed that results were maintained.
Morgan C, Stevens CA. Changes in perceptions of risk and competence among beginning scuba divers.
Journal of Risk Research. 2008; 11: 951-966.
Abstract: The adventure experience paradigm theorizes that individuals engaging in high- risk recreation exhibit changes in perceptions of risk and competence. While previous research has examined changes in perceptions for individuals engaged in short-term, high-risk recreation, there is no research examining patterns of perceptual change through extended involvement in risk recreation activities. The purpose of this study was to examine changes in perceived risk and perceived competence throughout a 14-week basic scuba diving course. Participants (n557) completed the dimensions of an adventure experience (DAE) at the start and end of the course as well as before and after their first time on scuba, first open water dive, and first off shore dive. Changes in perceived risk and perceived competence were examined. Results indicated a significant decrease in perceived risk and a significant increase in both competence factors (attitudes and abilities) pre-to-post course and at most time intervals. Although statistically significant, changes in perceived risk and attitude may be of less practical significance (around 0.6 on a 10-point scale). However, perceived ability increased more noticeably (2.6 on a 10 point scale). The findings of this study support and further confirm the literature, which indicates repeated involvement in high-risk recreation decreases participants' perceptions of risk and increases perceptions of competence. Recommendations include further study of DAE psychometrics and research on how changes in perceptions of risk and competence are related to outcomes in adventure recreation.
Ladd G. Treatment of psychological injury after a scuba-diving fatality.
Diving and Hyperbaric Medicine. 2007; 37: 36-39.
Abstract: After the death of a student during an ocean scuba training dive, the student's diving instructor was suffering from Acute Stress Disorder, a post-traumatic stress reaction. The treatment of the instructor's distress using a combination of two recognized trauma therapies: Eye movement desensitization and reprocessing (EMDR) and cognitive-behaviour therapy (CBT) is described. Improvement was noted after four treatment sessions. The instructor reported further improvement at a two-month follow-up and the positive effects were maintained nineteen months later.
Nicholson N, Soane E, Fenton-O'Creevy M, Willman P. Personality and domain-specific risk taking.
Journal of Risk Research. 2005; 8: 157-176.
Abstract: The concept of risk propensity has been the subject of both theoretical and empirical investigation, but with little consensus about its definition and measurement. To address this need, a new scale assessing overall risk propensity in terms of reported frequency of risk behaviours in six domains was developed and applied: recreation, health, career, finance, safety and social. The paper describes the properties of the scale and its correlates: demographic variables, biographical self-reports, and the NEO PI-R, a Five Factor personality inventory (N52041). There are three main results. First, risk propensity has clear links with age and sex, and with objective measures of career-related risk taking (changing jobs and setting up a business). Second, the data show risk propensity to be strongly rooted in personality. A clear Big Five pattern emerges for overall risk propensity, combining high extraversion and openness with low neuroticism, agreeableness, and conscientiousness. At the subscale level, sensation-seeking surfaces as a key important component of risk propensity. Third, risk propensity differs markedly in its distribution across job types and business sectors. These findings are interpreted as indicating that risk takers are of three non-exclusive types: stimulation seekers, goal achievers, and risk adapters. Only the first group is truly risk seeking, the others are more correctly viewed as risk bearers. The implications for risk research and management are discussed.
Raglin JS, Stegner AJ. Psychobiological aspects of panic in SCBA and SCUBA. G.
International Journal of Sport and Exercise Psychology. 2005; 3: 446-454.
Abstract: This review focuses on a series of survey and experimental investigations, led by Professor William P. Morgan, designed to examine the role of panic and anxiety in the etiology of diving-related accidents and deaths. A significant proportion of scuba fatalities have been attributed to panicking while submerged, but these estimates should be considered conservative at best. Morgan's work has demonstrated that most divers report experiencing panic or near-panic incidents at some point in their diving careers and that the phenomenon is not limited to novice or inexperienced divers. Trait anxiety has proven to be a reliable predictor of those individuals prone to panic behavior while wearing a self-contained breathing apparatus, both above and underneath water. Additional investigations have suggested that environmental influences, such as water temperature and thermal apparel, could also be critical factors in the development of panic while diving. Employing a psychobiological perspective, Morgan's research has made an impressive and indelible contribution to the future safety of scuba divers and to the field of sport psychology.
Miller G, Taubman-Ben-Ari O. Scuba diving risk taking--a terror management theory perspective.
Journal of Sport & Exercise Psychology. 2004; 26: 269-282.
Abstract: This study examined, from a Terror Management Theory (TMT) perspective, the effects of death reminders on the tendency to take risks in diving. All participants (N = 124) completed Rosenberg's self-esteem scale and a diving related self-efficacy questionnaire. Then half of them were exposed to a mortality salience induction and the other half to the control condition. The dependent variable was self-reported intentions to take risks in diving. Findings showed that mortality salience led to greater willingness to take risks in diving vs. control condition, but only among divers with low self-esteem and low diving related self-efficacy. In addition, mortality salience led to less willingness to take risks in diving vs. the control condition only for low self-esteem divers who possessed high diving related self-efficacy. However, no effects were found for high self-esteem persons. The results are discussed in view of the self-enhancing mechanisms proposed by TMT, offering practical implications regarding the need to increase divers' self-esteem and self-efficacy as a preventive strategy.
Morgan WP, Raglin JS, O'Connor PJ. Trait anxiety predicts panic behavior in beginning scuba students.
International Journal of Sports Medicine. 2004; 25: 314-22.
Abstract: Recreational scuba diving is associated with a significant number of fatalities and decompression illnesses each year, and there is evidence that permanent neuropsychological injury can occur in divers. There is also evidence that the principal cause of decompression illness and fatalities in divers is rapid ascent, and it appears that the primary stimulus for rapid ascent is panic. The primary purpose of this investigation was to evaluate the extent to which an objective measure of trait anxiety could be effective in predicting panic behavior in students undergoing scuba training. Trait anxiety was assessed at the outset of scuba instruction in 42 students, and the instructor recorded instances of panic behavior during the 4-month course. It was predicted that individuals scoring 39 or greater on the trait anxiety sub-scale of the State-Trait Anxiety Inventory would be more likely to experience panic behavior than individuals with scores below this cut-off. Predictions and actual recordings of panic behavior were performed independently using a blinded paradigm. Eleven of the students exhibited panic behavior on two or more occasions during the instruction, and 35 of 42 (83 %) predictions were accurate (p < 0.001). It is concluded that an objective measure of trait anxiety can be employed a priori for prediction of panic behavior in beginning scuba students.
Ramírez J, Villaverde C, Oltras C, Ruíz-Villaverde R, Sánchez-Caravaca M. Levels of ACTH and β-endorphin in the response to stress from open sea scuba diving to 25 m (3.5 ATA). A field study.
International Journal of Sport Psychology. 2004; 35: 1-12.
Abstract: To investigate the endocrine response (ACTH and beta-endorphin) to scuba diving in the open sea, in individuals with different levels of training. Materials and methods: Samples of blood and urine were obtained from two groups of divers: El (n=6) had over 4 years' experience, with frequent dives below 35 m; E2 (n=6) had 3 years' experience or less and had not dived below 15 m. A sedentary control group (n=11), who did not practice sports, was evaluated to establish basal measurements. The test consisted of submersion in the open sea to a depth of 25m (3.5 ATA).
Results: In El, there was a presubmersion increase in plasma levels of ACTH and beta-endorphin (p<0.05) and a significant decrease after the test. In E2, levels of these hormones were significantly higher after submersion (p<0.05).
Discussion: These changes are related to an anticipation phenomenon in the El group, in which adaptive mechanisms to hyperbaric submersion come into play, due to their greater experience than the E2 group. The submersion itself did not present an additional stimulus for the members of the El group, which explains the fall in hormone levels observed after the test.
Slosman DO, de Ribaupierre S, Chicherio C, Ludwig C, Montandon M-L, Allaoua M, Genton L, Pichard C, Grousset A, Mayer E, Annoni J-M, de Ribaupierre A. Negative neurofunctional effects of frequency, depth and environment in recreational scuba diving: the Geneva "memory dive" study.
British Journal of Sports Medicine. 2004; 38: 108-114.
Abstract: Objectives: To explore relationships between scuba diving activity, brain, and behaviour, and more specifically between global cerebral blood flow (CBF) or cognitive performance and total, annual, or last 6 months' frequencies, for standard dives or dives performed below 40 m, in cold water or warm sea geographical environments.
Methods: A prospective cohort study was used to examine divers from diving clubs around Lac Le _ man and Geneva University Hospital. The subjects were 215 healthy recreational divers (diving with self-contained underwater breathing apparatus). Main outcome measures were: measurement of global CBF by 133Xe SPECT (single photon emission computed tomography); psychometric and neuropsychological tests to assess perceptual-motor abilities, spatial discrimination, attentional resources, executive functioning, and memory; evaluation of scuba diving activity by questionnaire focusing on number and maximum depth of dives and geographical site of the diving activity (cold water v warm water); and body composition analyses (BMI).
Results: (1) A negative influence of depth of dives on CBF and its combined effect with BMI and age was found. (2) A specific diving environment (more than 80% of dives in lakes) had a negative effect on CBF. (3) Depth and number of dives had a negative influence on cognitive performance (speed, flexibility and inhibition processing in attentional tasks). (4) A negative effect of a specific diving environment on cognitive performance (flexibility and inhibition components) was found.
Conclusions: Scuba diving may have long-term negative neurofunctional effects when performed in extreme conditions, namely cold water, with more than 100 dives per year, and maximal depth below 40 m.
Todd SL. Only "real divers" use New York's Great Lakes. In Murdy J (Ed.), Proceedings of the 2003 Northeastern Recreation Research Symposium (pp. 211-218). Rep. NE-317. Newtown Square, PA: U.S. Department of Agriculture, Forest Service, Northeastern Research Station.
Abstract: Great Lakes divers pride themselves in being hardy, tough, and robust in order to dive under innately challenging environmental conditions, suggests qualitative focus group data collected from New York SCUBA divers. Since Great Lakes participants tend to dive in both fresh and saltwater, dive three or four seasons a year, belong to dive clubs, and subscribe to dive magazines more often than other divers, it was hypothesized that these segments of divers would report lower degrees of constraints. In 1999, a total of 869 New York State divers returned mail surveys (37% response rate). Divers with Great Lakes experience did report significantly lower constraint levels for 7 of 11 factors than divers who had not used these lakes. All other hypothesized relationships were also supported; divers using both fresh and saltwater tended to experience constraints to a lower degree (differing significantly on 6 factors), as did year-round divers (10 factors), dive club members (6 factors), and magazine subscribers (7 factors), with one exception: magazine subscribers experienced higher degrees of constraint for conflict with other users. These results suggest that Great Lakes divers are able to negotiate perceived constraints more successfully than other types of divers, supporting the notion that they are a hardier and more robust “breed.” In addition, dive clubs and magazines also seem to be associated with lower levels of constraint, suggesting their socializing, supportive, and educational influence on divers.
Watson AE, Pulford BD. Personality differences in high risk sports amateurs and instructors.
Perceptual & Motor Skills. 2004; 99: 83-94.
Abstract: This study investigated the personality differences of 21 amateurs and 20 instructors who participated in the high risk sports of skydiving, hang-gliding, paragliding, scuba diving, microlighting, and rock climbing, versus those who did not. 38 men and 28 women (M age = 32.6 yr., 51)= 10.0) were assessed using the Eysenck Personality Questionnaire-Revised, the General Health Questionnaire, the Generalised Self-efficacy Scale, and a Type A/B personality measure. Instructors and Amateurs scored significantly higher on Extroversion and lower on Neuroticism than Nonparticipants; however, they differed from each other on the General Health Questionnaire and Type A/B personality scores. Amateurs scored significantly higher on Psychoticism and Self-efficacy than Instructors and Nonparticipants. In conclusion, these test scores suggest that people who are attracted to high risk sports tend to be at the extroverted and emotionally stable end of the scale, with a tendency to exhibit Type A characteristics; however, Instructors' scores on Psychoticism and Self-efficacy are more akin to those of Nonparticipants.
Ness GJ, Macaskill N. Preventing PTSD: the value of inner resourcefulness and a sense of personal control of a situation. Is it a matter of problem-solving or anxiety management?
Behavioural and Cognitive Psychotherapy. 2003; 31: 463-466.
Abstract: The accounts of five subjects who survived life threatening experiences without the development of PTSD were examined, focusing on the coping strategies and cognitions described in these situations. The study aimed to determine whether there was a common pattern of response amongst subjects in these situations similar to the cognitive patterns described by the senior author of the previous case study (Ness & Macaskill, 2000) who survived a near drowning experience without the development of PTSD. In the search for common coping strategies all five respondents in the study completed the Locus of Control Scale (Rotter, 1966) and the Self-Control Schedule (Fisher & Reason, 1988). All five respondents demonstrated the use of problem solving as their main cognitive strategy, utilizing specific information from their previous experience relevant to their life-threatening situation. Respondents did not appear to rely on coping strategies aimed at the management of acute anxiety symptomatology. There was no common pattern among respondents in profiles on the Self-Control Schedule or the Locus of Control Scale. The possible implications of this case series study are discussed in relation to opportunities for the prevention of PTSD, the use of debriefing and the treatment of post-traumatic stress.
Anegg U, Dietmaier G, Maier A, Tomaselli F, Gabor S, Kallus KW, Smolle-Jüttner FM. Stress-induced hormonal and mood responses in scuba divers: A field study.
Life Sciences, 2002; 70: 2721-2734.
Abstract: Examined the relationship between self-reported emotional state and the hormonal and respiratory responses of scuba divers during stressful and non-stressful (recreational) dives. The 15-55 yr old male Ss were divided into 2 groups of 7 divers each with opposite stress coping strategies. Measured parameters included total air consumption, plasma hormone levels of epinephrine, norepinephrine and prolactin, and saliva cortisol levels. Results show that prolactin was a hormonal marker with a significant increase in the sub-group of stress-controllers. Along with the self-reported emotional conditions under immersion, these data suggest that an increased prolactin level reflects a state of elevated physical and mental activation and vigilance. Facing a stressful situation, Ss with more emotional concern and the tendency to surrender react by "blunted responses" showed significantly lower elevations of prolactin levels, in contrast to Ss with the opposite psychological features. The other somatic parameters (epinephrine, norepinephrine) showed significant increases during and after dives (with the exception of saliva cortisol), but without any significant group difference.
Ladd G, Stepan V, Stevens L. The Abacus Project: establishing the risk of recreational scuba death and decompression illness.
South Pacific Underwater Medical Society Journal. 2002; 32: 124-128.
Abstract: In order to establish the relative risk of death and non-fatal decompression illness (DCI) in recreational scuba diving in British Columbia (BC), Canada, a field survey was conducted. For 14 months, every dive shop and charter operator in the province of BC was asked to count the number of scuba tanks that were filled for use in recreational scuba diving. For the same 14 month period, hyperbaric chambers reported the number of BC divers treated for non-fatal DCI and the provincial coroners records were reviewed for scuba fatalities. Over the 14 months that scuba tank fill information was collected, an average of 65% (range: 60-71%) of the fill stations reported. Death and DCI incidence rates were calculated based on the 146,291 fills reported by the participating stations. During this same period there were 3 fatalities and 14 cases of non-fatal DCI. The incidence of recreational scuba death was 0.002% (2.05/100,000 dives). The incidence of non-fatal DCI was 0.010% (9.57/100,000 dives). Results are discussed in light of this being the first time a reasonably reliable measure of diving activity has been achieved in a large geographic area over an extended time period.
Taylor D, O'Toole KS, Auble TE, Ryan CM, Sherman DR. The psychometric and cardiac effects of pseudoephedrine in the hyperbaric environment.
Pharmacotherapy. 2000; 20: 1045-1050.
Abstract: Study Objectives: To examine the psychometric and cardiac effects of pseudoephedrine at 1 and 3 atmospheres (atm) of pressure (0 and 66 feet of sea water, respectively), and to make recommendations about the agent's safety in the diving environment.
Design: Double-blind, placebo-controlled, crossover study.
Setting: Monoplace hyperbaric chamber of a university hospital.
Subjects: Thirty active divers (mean age 38 yrs).
Intervention: A bank of seven tests was used to assess cognitive function during four different simulated dive combinations: placebo-1 atm, placebo-3 atm, pseudoephedrine-1 atm, and pseudoephedrine-3 atm.
Measurements and Main Results: Heart rate and cardiac rhythm were recorded during all dives. Repeated-measures analysis of variance was used to analyze the effects of pseudoephedrine, depth, and drug-depth interaction. No significant, independent effects of pseudoephedrine were seen on any of the seven psychometric test scores (p>0.05), although the drug tended to increase anxiety scores (p=0.092). Depth resulted in a significant increase in anxiety scores (p=0.021) and a significant decrease in verbal fluency test scores (p=0.041); it had no significant effects on the other five psychometric tests (p>0.05). Pseudoephedrine caused a significant increase (p=0.036) in mean heart rate, and depth caused a significant decrease (p=0.013). Neither pseudoephedrine nor depth affected cardiac rhythm.
Conclusion: Pseudoephedrine does not cause significant alterations in psychometric performance at 3 atm of pressure that might increase the risk of diving. Depth causes significant adverse effects on anxiety levels and semantic memory at 3 atm. Pseudoephedrine and depth have significant but opposite effects on heart rate; although, these effects are unlikely to be clinically significant during diving. It is unlikely that pseudoephedrine adds significant risk to the diver.
Wang J, Akirav I, Richter-Levin G. Short-term behavioral and electrophysiological consequences of underwater trauma.
Physiology & Behavior. 2000; 70: 327-332.
Abstract: In a previous work we found that a 30-s underwater trauma, following 8 days of training for a spatial memory task in the water maze, resulted in poor performance in the spatial memory task at both 1 h and 3 weeks after the trauma. Here we found that compared with naive animals and animals that were trained for the spatial learning task but were not traumatized, the traumatized rats showed impaired performance in a spatial learning task in the water maze 20 min after the trauma and a reduced level of dentate gyrus long-term potentiation (LTP) 40 min after high-frequency stimulation to the perforant path. We also found a positive correlation between the behavioral performance and hippocampal plasticity. The reduced ability to induce LTP suggests that the trauma-related behavioral impairment is mediated by hippocampal dependent processes. The underwater trauma may provide an important and potentially powerful model for understanding the mechanisms underlying the relationship between stress, cognition, and learning.
Raglin JS. Psychobiological antecedents of panic in scuba diving.
Performance in Extreme Environments. 1998; 3: 26-29.
Abstract: While scuba diving has been promoted as a safe activity, it is not free from risk. From 1970 to 1993, the number of yearly scuba diving fatalities in the US has averaged 104. Despite improvements in training and equipment design, this figure has remained essentially unchanged, averaging 101 for 1994 and 1995, according to the most recent data available. Depending on the estimate of active recreational divers, the relative risk of death while diving may be as high as 3.84 per 100,000 divers. While the majority of these deaths can be ascribed to known causes such as injury or equipment failure, the precipitating factors in up to 40% of fatalities remains unknown. Many of these unexplained deaths have been attributed to psychological variables, in both recreational and professional diving. In particular, anxiety and panic are widely regarded to be the primarily psychological factors in diving accidents and fatalities. This article summarizes (1) survey research on panic in scuba diving, (2) psychological approaches to predicting panic in stressful exercise settings, and (3) psychobiological studies of anxiety and physical performance. Despite views to the contrary, panic behavior is not a rare occurrence in scuba diving.
Richter-Levin G. Acute and long-term behavioral correlates of underwater trauma - potential relevance to stress and post-stress syndromes.
Psychiatry Research. 1998; 79: 73-83.
Abstract: As a consequence of a brief but significantly extreme stressor, an individual will experience a stress response, which may sometimes develop into Acute Stress Disorder (ASD) or Post-Traumatic Stress Disorder (PTSD). Though a rat model for ASD and PTSD is not expected to encompass the richness and complexity of the disorders in humans, it will enable the study of the common underlying mechanisms that generate the disorders, the study of pre-trauma etiological aspects of the disorders and the screening of drugs with potential relevance to the treatment of the disorders. One well-documented aspect of PTSD is the enhancing influence of contextual elements on the appearance of symptoms of the post-stress trauma. To exploit this effect, we have chosen to assess the effects of an underwater trauma in the Morris water maze since the effects of such trauma on memory and attention can be later evaluated in the context of the trauma. At both 1 h and 3 weeks after the trauma, significant behavioral deficits were observed in the water maze. The effects of the underwater trauma on the performance of rats in the water maze were context specific. Underwater trauma in a different (out-of-context) water container had no effects on the ability of rats to perform a spatial memory task in the water maze. An elevated level of anxiety was found in the plus maze test, independently of whether the trauma was performed in the water maze or in a different (out-of-context) water container. The results indicate that a within-context underwater trauma has both acute and lasting behavioral consequences which can be assessed using a spatial memory test in the context of the trauma. The results are discussed in relation to their relevance to stress and PTSD.
Morgan WP. Anxiety and panic in recreational scuba divers.
Human Performance in Extreme Environments. 1996; 1: 20-35.
Abstract: Explores issues concerning the role of anxiety and panic in recreational diving fatalities. A review of the accident and mortality statistics occurring within the dive community is presented and the classifications associated with such fatalities are addressed. The author offers an understanding of the behavioral and performance issues associated with operating a self-contained underwater breathing apparatus in the underwater environment. Findings are employed from research with populations (firefighters and athletes) operating in similar conditions with a self-contained breathing apparatus, and how stress and anxiety can mediate the behavior and performance of users operating such systems are illustrated. Psychological characteristics of divers are explored, along with their overall anxiety levels as compared to other populations. It is argued that this research illuminates the need for implementing a psychological component to the curriculum of open-water certification programs to decrease the risks associated with the panic and anxiety of recreational divers. Psychological interventions are discussed for reducing and/or training divers for coping with panic and anxiety occurring underwater.
Hunt J. Psychological aspects of scuba diving injuries: Suggestions for short-term treatment from a psychodynamic perspective.
Journal Clinical Psychology in Medical Settings. 1996; 3: 253-71.
Abstract: Examined psychological reactions to decompression sickness in 3 experienced scuba divers using a psychodynamically-oriented, interview-based approach. These cases are part of a larger study of risk and injury among sport divers ( J. Hunt; 1993, 1995, 1996). Case I (male, aged 29 yrs), Case II (female), and Case III (female, in her 30s) all took diving risks and experienced denial, depression, shame, among other emotions as a result of their errors in judgment. However, their individual reactions also corresponded to other areas of their lives (i.e., familial relationships, occupation, social relationships), which, in turn, affected their reactions to injury. An argument is made that most research studying risk behavior and sports take into account biological, behavioral or cognitive approaches, while ignoring unconscious conflict in risk-taking and injury management.
Hunt J. Diving the wreck: Risk and injury in sport scuba diving.
Psychoanalytic Quarterly. 1996; 65: 591-622.
Abstract: Uses psychoanalytic theory to examine risk and injury in the case of a male deep sea diver. The author examines the unconscious conflicts that appeared to fuel the diver's involvement in deep diving and to lead to a near fatal incident of decompression sickness. Particular attention is paid to the role of the diver's father in the evolution of the preoedipal and oedipal fantasies and conflicts that appear to be linked to the injury. The author's research, which thus far has been based on interviews with and fieldwork among 36 recreational and deep divers, is presented.
Raglin JS, O'Connor PJ, Carlson N, Morgan WP. Responses to underwater exercise in scuba divers differing in trait anxiety.
Undersea & Hyperbaric Medicine. 1996; 23: 77-82.
Abstract: Fifteen male scuba divers performed underwater leg ergometer exercise in an effort to determine if trait anxiety was related to their physiologic or perceptual responses. Psychological assessment completed before exercise testing revealed that the sample exhibited positive psychological profiles. However, five individuals possessed trait anxiety scores above the published mean (M = 46.0). Their responses to exercise were compared with the five participants with the lowest trait anxiety scores (M = 30.6). The exercise task was 20 min of steady-state underwater leg ergometer exercise. Oxygen consumption, CO2 production, minute ventilatory volume, breathing frequency, and heart rate were assessed at rest and every 5 min during exercise. Perception of effort and breathing discomfort were also determined during exercise. Each of the physiologic and perceptual variables increased (P < 0.05) with exercise. The only group main effect (P < 0.05) occurred for respiration rate. The high trait anxious group took 7.4 fewer breaths per minute (13.1 vs. 20.5) compared with low trait anxious group. These results have implications regarding the use of intervention strategies in persons at potential risk of experiencing panic while scuba diving.
Hunt J. Divers' accounts of normal risk.
Symbolic Interaction, 1995; 18: 439-462.
Abstract: This research examines how divers learn to expand notions of risk to include practices that violate formal training and may increase vulnerability to injury. Cultural constructions of "normal" or acceptable risk are learned in interaction with experienced divers who define the rules of membership and provide accounts that excuse or justify participation in high-risk activities. The research explores how novice divers learn to distinguish categories of formal, normal, and excessive risk as they expand their risk involvement and attempt to achieve membership in the deep diving subculture. The study concludes with a discussion of risk normalization in everyday life and other leisure and occupational subcultures.
Edmonds C, Walker C. Scuba diving fatalities in Australia and New Zealand: 1. The human factor.
South Pacific Undersea Medicine Society Journal. 1989; 19: 94-104.
Abstract: In Australia and New Zealand (ANZ), the diving death data collected is more detailed and is comprehensively catalogued. It is collated as "Project Stickybeak". This report is the first of three extensions of "Project Stickybeak", and deals with an analysis of the human factors contributing to diver death. It encompasses medical information, psychological problems and various diving techniques that imply questionable judgement. They observe that descriptions of panic and fatigue occur frequently throughout the fatality case reports. To dismiss them because of the inability to demonstrate morbid pathology, would be to ignore two of the major contributory causes of diving deaths.
Griffiths TJ. The effects of relaxation and cognitive rehearsal on the anxiety levels and performance of SCUBA students.
International Journal of Sport Psychology. 1985; 16: 113-119.
Abstract: 48 undergraduate beginning SCUBA students trained during 1 semester (control) and 63 undergraduate beginning SCUBA students trained during a 2nd semester (relaxation/cognitive rehearsal [RCR]) received similar training with the exception that the RCRs listened, on 3 occasions, to an audiotaped program designed to reduce diver state anxiety and improve underwater performance. Ss completed baseline measures of the State-Trait Anxiety Inventory (STAI) and a stimulus-response inventory of general trait anxiousness. Ss were reassessed on the STAI prior to performance evaluations of the deepwater quarry dive and the bail-out procedure that required Ss to don and remove SCUBA equipment. Results reveal significantly lower levels of state anxiety in the RCRs than in the controls prior to both the bail-out and deepwater quarry dive performances. A significant performance difference between these same groups was found only in the bail-out maneuver, suggesting that RCR must be task specific in order to positively modify performance.
Griffiths TJ, Steel DH, Vaccaro P. Anxiety of scuba divers: A multidimensional approach.
Perceptual and Motor Skills. 1982; 55: 611-614.
Abstract: The research examined the relationships between trait anxiety and state anxiety levels of 33 male and 15 female beginning SCUBA students prior to two difficult underwater tests. Both a uni-dimensional and a multi-dimensional measure of trait anxiety were used. S-R General Trait Anxiousness was a more useful instrument than the uni-dimensional STAI-Trait scale in predicting levels of state anxiety prior to underwater testing.
Vaernes RJ. Eidsvik S. Central nervous dysfunctions after near-miss accidents in diving.
Aviation Space & Environmental Medicine. 1982; 53: 803-807.
Abstract: The possible differences in specific central nervous system functions in 2 groups of divers were studied: Divers with a history of diving accidents (accident group, N = 9) and accident-free divers (non-accident group, N = 15). Both groups were characterized with a mean I.Q. level (WAIS) within the normal range. Of the nine accident group divers, 8 showed abnormalities on neuropsychological tests implicating lesions on higher CNS levels. In addition, five of the accident group divers had a syndrome of subcortical/limbic dysfunctions--specific memory deficits, low autonomic reactivity, sustained attention problems, and emotional lability. The data confirmed previous findings that a severe diving accident may lead to cerebral dysfunctions. However, in contrast to the previous studies, our study indicated that divers with average intellectual levels can develop specific CNS dysfunctions after a near miss diving accident. Therefore, we conclude that a combined effect of emboli with multifocal lesions and/or a more specific effect on limbic structures represent the pathophysiology of a severe near-miss diving accident.
Griffiths TJ, Steel DH, Vaccaro P, Karpman MB. The effects of relaxation techniques on anxiety and underwater performance.
International Journal of Sport Psychology. 1981; 12: 176-182.
Abstract: Investigated the effects of 2 relaxation techniques on the levels of self-reported anxiety and physiological stress among SCUBA divers prior to an underwater task. In addition, the effect these relaxation techniques have on actual performance of a difficult underwater task was investigated. 50 college students from a beginning SCUBA class were randomly assigned to either a biofeedback relaxation group, a meditation group, or a control group. Ss were administered the State-Trait Anxiety Inventory, and physiological measures of heart rate, respiration rate, hand temperature, and frontalis muscle action potential were taken before and after relaxation training. Data indicate that differences existed between the 3 groups on measures of state anxiety following relaxation training. Significant correlations were detected between state anxiety and performance and between trait anxiety and performance.
Mears J, Cleary P. Anxiety as a factor in underwater performance.
Ergonomics. 1980; 23: 549-557.
Abstract: 24 male and 8 female experienced (3-30 hrs) scuba divers (average age 23 yrs) were divided in 4 groups, and each group made 1 dive to 6 or 30 m in day or night conditions. Manual dexterity, time estimation, and cognitive performance (Raven's Progressive Matrices) data were obtained on the surface and under water; heart and respiration rates were monitored before and during the dive. Ss completed the State-Trait Anxiety Inventory Scale X-1 before and after the dive. Both anxiety and heart rate decreased under water in the 6-m groups and increased in the 30-m groups, but respiration rates remained elevated throughout. A 14-30% decrease in manual dexterity occurred at 6 m and a 45-47% decrease at 30 m; cognitive performance improved at 6 m but decreased 26-36% at 30 m. There was a 15% decrease in manual dexterity at 6 m in the day and 30% at night; for the 30-m group, decreases of 45 and 47% were found for day and night conditions, respectively. Although time estimation varied greatly on the surface, all Ss tended to overestimate a time standard under water. Results support the notion that anxiety is a contributory factor in performance decrements under water.
Griffiths TJ, Steel DH, Vaccaro P. Relationship between anxiety and performance in scuba diving.
Perceptual and Motor Skills. 1979; 48: 1009-1010.
Abstract: The research examined the relationship between the anxiety levels of 62 beginning scuba diving students and standardized performance tests from the YMCA training program. Results suggested that there was no relationship between anxiety and performance on relatively simple tasks, while there was a relationship between anxiety and performance on the more complex diving maneuvers.
Terry PC, Mayer JL, Howe, BL. Effectiveness of a mental training program for novice scuba divers.
Journal of Applied & Sport Psychology. 1978; 10: 251-267.
Abstract: The purpose of the study was to assess the effects of a mental training program on state anxiety, respiration rate and performance of novice scuba divers. Forty-four participants enrolled in novice open water diving courses served as participants. An intervention group (n = 15), in addition to scuba training, received an audiotaped mental training program designed to reduce anxiety and improve diving performance. A placebo-control group (n = 15) followed the same procedures except that their audiotape contained general information about scuba diving. A control group (n = 14) received only scuba training. The intervention group re-ported lower pre-dive scores for cognitive anxiety, higher pre-dive scores for self-confidence, performed better on bail-out and mask removal tasks, and showed lower respiration rate than either control group. Respiration rate and somatic anxiety scores significantly predicted bail-out performance. Respiration rate also predicted mask removal performance. These results suggest that novice divers may benefit from mental training as part of their pre-dive instruction.
Griffiths TJ, Steel DH, Vaccaro P. Anxiety levels of beginning scuba students.
Perceptual and Motor Skills. 1978; 47: 312-314.
Abstract: Anxiety levels of 29 beginning scuba students in college classes were determined at rest and prior to standardized scuba tests. Resting trait and state anxiety levels were significantly lower than norms. Only moderate increases in state anxiety were noticed throughout the testing sequence.
Biersner RJ, Ryman DH. Prediction of scuba training performance.
Journal of Applied Psychology. 1974; 59: 519-521.
Abstract: 296 trainees of the US Navy School for Divers Second Class completed a demographic questionnaire, a health inventory, and an attitude survey. Significant multiple correlations in a validation sample and in a cross-validation sample were obtained between these variables and a pass-fail performance criterion. Scales dealing with mental health and training apprehension were the most significant predictors.
Dimmock K. Ghazali M (Eds). Scuba Diving Tourism. London: Routledge; 2013.
Edmonds C, McKenzie, B. Thomas, R. Pennefather J. Diving medicine for scuba divers, 5th ed. pdf e-book, free internet edition; 2013. Retrieve from www.divingmedicine.info
Edge M. The Mindset of the successful underwater photographer, Ch. 5: 165-214. In The Underwater Photographer (4th Ed.). Amsterdam: Elseiver/Focal Press; 2010.
St. Leger Dowse M Fife CE (Eds). Women and Pressure: Diving and Altitude. Flagstaff: Best Publishing; 2010.
Jensen Stedl K, Stedl T. Yoga for Scuba Divers: Practice on land to build strength, increase your air efficiency, and become a better diver. Seattle: 8th Element Recreation LLC; 2007.
Dash M. Conquering your fear of water: An innovative self-discovery course in swimming. Bloomington: AuthorHOUSE; 2006.
Ange M. Diver Down: Real-World SCUBA Accidents and How to Avoid Them. Camden ME: International Marine/Ragged Mountain Press; 2005.
Piantadosi CA. The biology of human survival: Life and death in extreme environments. Oxford: Oxford University Press; 2003.
Edmonds C, Lowry C, Pennefather J, Walker R. Diving and subaquatic medicine, 4th ed. London: Edward Arnold Publishers; 2002.
Chowdhury B. The last dive: A father and son's fatal descent into the ocean's depths. New York: Harper Collins; 2000.
Nevo B, Breitstein, S. Psychological and behavioral aspects of diving. Flagstaff: Best Publishing; 1999.
Bachrach AJ, Egstrom GH. Stress and performance in diving. San Pedro: Best Publishing; 1987.