INTRODUCTION

The foundation of any managed breeding programme for animals living in captivity is a studbook. This is the chronological listing of animals in the historical captive population detailing birth and death dates, gender, parentage, locations, transfers and local identification numbers (Glatston, 1986). Analyses of these data provide critical information on past trends in population size, age-specific reproductive and survival rates, age structure, numbers of founders, degree of inbreeding, loss of genetic diversity and other measures useful for evaluating temporal changes in a captive population. This information then becomes the basis for making management recommendations to enhance the demographic and genetic security of the captive population (Ballou & Foose, 1996). Demographic security is needed to ensure that an adequate number of breeding-aged animals are available to reproduce at the rates needed to grow or maintain the population at its desired size. Genetic diversity is required for the population to remain healthy and to adapt to changing environments (i.e. experience natural selection).

The 2001 International Studbook for the Giant Panda contains detailed life history information on 542 giant pandas that have lived in zoos around the world (Xie & Gipps, 2001). The first entry, giant panda Studbook (SB) Number 1, is Su Lin, a wild-caught female who arrived at Brookfield Zoo on 2 February 1937 (see Chapter 1). A quick scan of the studbook leaves one with the impression that the captive population's dynamics are dominated by entry and subsequent death of wild-caught animals without sustainable reproduction.

INTRODUCTION

While many recent advances have been made in the breeding of giant pandas ex situ, historically this species has never reproduced well in captivity. Sexual incompatibility, health problems, low fecundity and a juvenile mortality rate in excess of 70% have contributed to low reproductive success (O'Brien & Knight, 1987; O'Brien et al., 1994; Peng et al., 2001a, b). Wild- and captive-born giant pandas, particularly those captured at a young age, traditionally had difficulty producing offspring in captivity upon becoming adults (Lu & Kemf, 2001). As a result, the ex-situ giant panda population has not been self-sustaining and, until recently, its growth has relied on introducing animals captured from nature. In some cases, this included individuals that appeared ill (rescues) or cubs that were believed to be neglected or abandoned by their mothers. Later field studies, however, revealed that females often leave cubs alone for four to eight hours while foraging, and in one documented case for 52 hours (Lu et al., 1994). Recently, China has placed a general moratorium on capturing wild giant pandas for captive breeding (Lu & Kemf, 2001), a move that forces the breeding community to develop a self-sustaining population.

The goal, however, is not only ensuring demographic self-sustainability but also the maintenance of genetic diversity. The deleterious effects of inbreeding are well recognised (O'Brien, 1994a; Frankham, 1995; Hedrick & Kalinowski, 2001; Frankham et al., 2002).

At first glance there seems little point in studying the aetiology of PTI. The very definition includes the cause. As Brett and Ostroff (1985) have pointed out, the hypothesis that a unique pattern of symptoms is caused by the experience of extremely stressful events is central to the inclusion of PTSD in the DSM. The threat and feelings of helplessness and vulnerability are thought to be uniquely destabilising of the victim's previous function. PTSD is defined as being the consequence of a traumatic event. In DSM-IV (American Psychiatric Association, 1994), PTSD is one of the few disorders for which the atheoretical approach is abandoned and the definition includes presumed aetiology. It is stated that ‘the essential feature of PTSD is the development of characteristic symptoms following exposure to an extreme traumatic stressor’. In the differential diagnosis section it is recorded that the stressor must be of an extreme (i.e. life-threatening) nature. This is in keeping with the definition in ICD-io (World Health Organisation, 1992).

It seems clear that the aetiology of PTI is connected with trauma, even though Scott (Scott and Stradling, 1994) has suggested that PTSD can occur in the absence of extreme trauma, and there has been serious debate about the necessity or otherwise of the stressor criterion (March, 1993). Breslau and Davis (1987a) have pointed out that there is ‘insufficient data to show that the set of symptoms characteristic of PTSD is strongly and uniquely associated with extraordinary stressors’.

It is the author's contention that this chapter is of great importance. With no apologies for repetition, it is emphasised that:

Although the term PTSD was put forward only in the late seventies and confirmed in 1980, there is no suggestion that the concept that exposure to major trauma can cause mental illness is new. It has long been recognised that trauma can be followed by mental illness. In an editorial addressing a different aspect of controversy surrounding PTSD, Andreasen (1995) reminds us that there was recognition of PTI in DSM-I but that at that time it was ‘conceptualised and defined psychologically’, that it was seen as being ‘by definition acute and reversible’ as it was included in ‘transient situational personality disorders’, and that no characteristic symptoms were specified. She sees the creation of PTSD as being required to meet the need of a generation of Vietnam veterans, many of whom had severe stress syndromes, and as it being a ‘general name’ because of the similarity of the syndrome across various stressors.

Essentially, DSM-I recognised that trauma could produce acute illness and implicitly indicated psychological causation. However, it did not describe a specific syndrome and saw chronic illness as representing precipitation or aggravation of a constitutional or potential disorder rather than a specific response to trauma.

Before we can examine normal reactions to trauma, it is necessary to come to some understanding of what is and is not normal. This may seem pedantic or simplistic, but it is not as simple as it seems.

The Oxford English Dictionary contains a large number of definitions of the word normal. Some are specific to physics or chemistry and are not relevant. Others include:

• the usual state or condition

• constituting, conforming to, not deviating or differing from, the common type or standard; regular, usual

• a normal variety of anything; that which, or a person who, is healthy and is not impaired in any way.

It is a little depressing to see that even The Oxford English Dictionary uses the word normal in the definition of the word normal. It seems that there are two relevant definitions of normal. One refers to the frequency of occurrence of the matter under study, that it is or is not the usual or common state. The other refers to an absence of disease. The two are not synonymous. For example, acne is probably statistically normal in adolescence but is not a healthy-normal. More dramatically, the statistically normal response to ingestion of an inoculum of Vibrio cholerae is probably to develop cholera.

It is fairly easy to define a concept of statistical normality. For example, the modal response might be considered to be the statistical norm.

Thus far this book has been intended to present the case for the importance and relevance of PTI in general and PTSD in particular. The aim of this chapter is to present some personal ideas and questions, and to try to consider the future direction of work on the psychological effects of trauma and the postulated physical effects in the brain of psychological trauma. It is unashamedly a personal view and is intentionally written without references, although hopefully the sources of most of the questions and problems have been detailed in the text thus far.

Trauma and mental illness are a subject which has inevitably preoccupied me over the years because of my employment. As a trainee psychiatrist in the army it seemed inevitable that I would be confronted with the history of battle shock and the future of combat stress in the anticipated battlefields of North West Europe. In the event the first case of PTI which I met was from one of the sad series of airline crashes which have come to be known by the name of the relevant city, or airfield, or flight number. What it taught me was the power of trauma and the intransigence of avoidance symptoms. A series of individual cases from Northern Ireland and from the Falklands taught me about PTI and then about PTSD. What they taught me was not so much the uniformity and the commonality of post-traumatic illnesses, but the variety of post-traumatic responses.

In this chapter we will look at the medicolegal connotations of PTI. Where there is a need specifically to address legal practice, the focus will be quite clearly upon the interaction of PTI and law in England and Wales. Aspects of American law have been addressed widely elsewhere, for example by Sparr (Sparr and Boehnlein, 1990) and others. Indeed, almost all of the work concerning PTI and criminal law, as well as much of that concerning civil law, comes from America. There are a number of useful books and pamphlets which specifically address the legal side of the psychiatric injury issues (Napier and Wheat, 1995) (Law Commission 1995) in England and Wales, or in areas with similar basis of law (Mullany and Handford, 1993). An attempt will be made in this chapter to examine both criminal and civil legal issues from the point of view of the expert clinician.

Probably more than any other form of mental illness, PTI is associated with medicolegal issues. It seems that in almost every case of PTI, be it PTSD or another condition, there is at least the potential for some form of legal or quasilegal consequence. There are a number of obvious areas of possible concern:

• PTI may be presented as a defence or mitigating factor in criminal cases

• PTI may be a consequence of criminal behaviour

• PTI may be a consequence of a civil wrong.

By definition, post-traumatic illness follows some sort of trauma. It has been recognised for many years that illness can follow trauma. However, what constitutes trauma is far from clear. In particular the type or extent of trauma necessary to cause PTSD is an issue which has been argued fiercely since PTSD was defined in DSM-III.

The whole concept of PTI is that it would not have occurred if it were not for a preceding trauma. The evidence is that there certainly is an excess of mental illness following major traumatic events, and this suggestion is not generally challenged.

The concept of PTSD in particular, on the other hand, demands more than that it be an illness which occurs in response to traumatic events. In addition it has to be an illness which occurs only following certain particular classes or severity of traumata, and which does not ever occur in the absence of such events. Is this backed by empirical evidence?

This chapter will look at the standing of illness following trauma, will examine the evidence for post-traumatic mental health problems, and will examine in detail the stressors which cause PTSD and the evidence that there is a specific pattern of illness which follows major trauma but which does not occur in other situations. The significance and meaning of the concept of qualifying events will be discussed. The changing status and definition of the stressor criterion in DSM will be considered and examined, as well as compared with ICD. Finally, the argument for the abolition of the stressor criterion will be examined.

This book is intended to be a brief but comprehensive textbook of the mental disorders or difficulties which can follow trauma and traumatic events. It is hard to argue with the suggestion that disasters, catastrophes, violence and traumatic incidents are all too common in modern society. Nobody would seriously suggest that previous centuries were idyllic peaceful times; natural disasters have always occurred. However, the sheer scale of the efforts which we have made to kill and maim each other this century has far outclassed the equally brutal but probably far less efficient activities of our forebears. Increased speed has its effect. Not only do we move around at greater and greater speeds, with the results of accidents being more horrific, but information moves around the world at faster and faster rates so that communication may be almost instantaneous. Some of the particular problems associated with the impact of trauma on the psyche could not have happened until the last decade. Only now can a mother sit at home and watch live footage of a shipwreck in which she believes that her son has drowned.

The frequency and diversity of traumatic events which may affect one person or thousands are such that the consequences of trauma will probably impinge upon all of us at some time. They will certainly impact upon the work of health and other service workers in general and mental health and social work professionals in particular.