The Depths: The Evolutionary Origins of the Depression Epidemic, by Jonathan Rottenberg

Depression is a major global mental health problem, which significantly affects the quality of life of many sufferers and their families. Despite medical and psychological advances, prevalence and relapse rates remain high. Why is this so? Why are we losing the battle? How do we explain the condition? These are some of the key questions posed by psychologist Jonathan Rottenberg. He rightly argues that it is time to take innovative mental health approaches to the current depression epidemic, and argues that the predominant “disease”, “deficiency” and “defect” view of depression is inadequate and inaccurate. The first challenge, he suggests, is to get the description of depression right, so that we can consider pathways towards recovery.

Rather than opt for the disease model of depression, Rottenberg takes a “mood science” view, arguing that this approach is different both historically and integratively. For, historically, we cannot understand why depressed moods are so prevalent until we first understand why we have the capacity for low mood. Integratively, people experience different stressors or forces simultaneously, which are thought to give rise, in turn, to mood. Thus, no single culprit can explain the depression epidemic.

Instead of a single-focus approach, Rottenberg suggests that a confluence of circumstances accounts for depression’s prevalence. He puts forward a strong evolutionary view of depressed mood, in which the mood system was hard-wired into our human make-up millions of years ago. But although low mood is considered adaptive and beneficial to the individual – in reserving personal resources and energy, for example – there are personal costs. In contemporary times, it is unclear when low mood is likely to be more beneficial than costly, or whether it will develop into deep depression. From the integrative perspective, Rottenberg also considers factors such as culture, society, motivation, and psychological processes focused on rumination, sense of loss and goal-setting. Unfavourable combinations of such factors may, he suggests, explain the high modern-day prevalence of depressed mood.

One of Rottenberg’s central arguments – and one made by many psychologists – is that understanding affective mood is key to understanding depression. It is hoped that this line of enquiry will ultimately stimulate new therapeutic paradigms in depression’s treatment and management. Among the contemporary psychological therapies that may offer some hope are acceptance, mindfulness and cognitive behavioural therapies, which involve strengthening the ability to tolerate negative thoughts as a means to break the cycle of rumination and depression.

Rottenberg also tackles the difficult question of recovery. From a mood perspective, he presents some approaches that may help to alter the trajectory of mood, such as modifying daily routines, resetting goals and disengaging from failing goals, changing how we interpret or react to mood, having a purpose in life, avoiding the sole pursuit of happiness in itself and recognising that happiness is a by-product of other goals. Although such strategies may provide clues to assist recovery, relatively little is known about the causal direction of these relationships or the underlying mechanisms that are effective. For example, does depression cause goal failure or does goal failure cause depression? Regrettably, the book’s consideration of recovery seems less convincing and persuasive than the chapters on depression itself.

The personal experience of depression that Rottenberg details here lends authenticity to his mood science-focused consideration of both the origins of the depression epidemic and why it remains so tenacious and difficult to treat. As The Depths shows, our age requires innovative psychological approaches if we are to tackle the growing burden of depression and, further, to promote well-being.