Anxiety

by Daniel Freeman

  That consensus began to change with the ground-breaking work of behavioural psychologists such as Stanley Rachman. The behaviourists argued that obsessions arise from conditioned anxiety. A person who learns to fear contamination, for instance, may become anxious at the sight or mere thought of dirt. When they wash themselves, their anxiety quickly subsides. And because washing makes them feel so much better, they’ll do it again the next time they feel anxious (this is an example of positive reinforcement).

  But Rachman and colleagues demonstrated that it isn’t necessary to use compulsions to reduce the anxiety triggered by obsessions. In what’s known as exposure and response prevention treatment, patients are taught to refrain from reacting compulsively. What they discover is that their anxiety will decrease all by itself. The debilitating cycle of obsession and compulsion is broken, and lasting improvement in OCD symptoms usually follows.

  Cognitive theories of OCD have built on the insights of behaviourist approaches. The main model has been formulated by Paul Salkovskis, who argues that what distinguishes the person with OCD is not unpleasant, intrusive impulses – as we’ve seen, almost everyone experiences those – but rather the way they interpret such impulses.

  At the core of that interpretation is the idea that, as Salkovskis puts it, ‘the person may be, may have been, or may come to be, responsible for harm or its prevention’ (either to oneself or others). So someone with OCD may believe that, if they don’t constantly wash themselves or clean their home, they or their loved ones will develop a fatal illness. A person disturbed by ideas of violence may believe that such thoughts prove they are a danger to others. And an individual who sees an image of their home in flames may fear that this is what will happen unless they repeatedly check that electrical appliances have been switched off. Salkovskis argues that these feelings of responsibility are generally the result of early life experiences – for example, the attitudes with which we were brought up.

  Understandably, such feelings can cause great anxiety. The person with OCD tries to rid themselves of that anxiety (and prevent the disaster they fear) through their compulsions. Unfortunately, although a compulsion may bring short-term relief, in the long run it only serves to maintain and indeed increase the anxiety. There are several reasons for this:

  • The compulsion draws the person’s attention to the obsessive thought, making it more likely to recur.

  • Compulsions are a form of safety behaviour. As we’ve seen, safety behaviours prevent us from discovering that our anxiety is exaggerated: someone who avoids physical contact with other people because they’re afraid of contamination is unable to learn that you can’t contract an illness by shaking hands.

  • Compulsions frequently involve unrealistic targets. Regardless of the precautions we take, we can never be certain that an accident won’t occur. No matter how long we spend washing and cleaning, absolute spotlessness is sure to elude us. The desire for cast-iron certainty leaves the person with OCD feeling that they could always do more – thereby fuelling their anxiety.

  • Many compulsions are inherently counterproductive. For example, people with OCD often try to suppress their obsessions. But trying not to think about something can make it more likely that you’ll do so, not less. (You can give this a go: try not to think about white bears.) And there’s evidence that people with OCD are less able to suppress thoughts than other people.

  • Repeated checking is a common feature of OCD. Yet checking doesn’t bring certainty: in fact, the more a person (even someone without psychological problems) checks something, the less sure they become. This is because repeated checking reduces the vividness of our memory, though not its accuracy. And because the memory seems less vivid, we distrust it – and thus check again.

  The cognitive behavioural therapy developed by Salkovskis and colleagues teaches the person with OCD to change the way they interpret their impulsive thoughts – to regard them as normal and inconsequential, rather than doom-laden reminders of personal responsibility – and to abandon the compulsions that fuel their anxiety.

  Biological perspectives

  Neurologically, OCD is distinct from the other anxiety disorders. The latter, as we saw in Chapter 2, are thought to involve problems in the amygdala, frontal lobes, and/or hippocampus. OCD, on the other hand, seems to be characterized by malfunction in a circuit comprising the orbitofrontal cortex, anterior cingulate cortex, striatum, and thalamus.

  (Hoarding, incidentally, is thought to engage different areas of the brain – which is one of the reasons some scientists feel it shouldn’t be categorized as a form of OCD. In fact, research led by David Mataix-Cols suggests that washing, checking, and hoarding each involve ‘distinct but partially overlapping neural systems’.)

  In especially severe cases of OCD – cases that respond neither to psychotherapy nor medication – surgery may be performed. (OCD is the only anxiety disorder to be treated by means of neurosurgery.) The operation, termed a cingulotomy, aims to break the OCD neurocircuit at the anterior cingulate. The success rate is moderate: a study of 44 patients operated on at Massachusetts General Hospital since 1989 found that 32% improved significantly, with a further 14% experiencing partial benefit. Some of these patients had undergone more than one cingulotomy.

  OCD seems to run in families, though not to any great degree. Having a first-degree relative with OCD elevates your own risk of developing the disorder from around 3% to 7%. Genetic heritability is thought to be modest. Twin studies of OCD are rare, but some have found no evidence of heritability. On the other hand, a twin study of OCD-like symptoms estimated heritability at 36%.

  Environmental perspectives

  With genes making a relatively limited contribution to OCD, the spotlight falls onto environmental factors.

  OCD has been linked to traumatic events in childhood (especially sexual abuse); relatively low socio-economic status; and hostile or neglectful parenting. However, these are also experiences that make a person vulnerable to anxiety disorders in general, and indeed to depression, alcohol and drug issues, and a wide range of psychiatric problems. The search for environmental influences specific to OCD continues.

  Chapter 10

  Post-traumatic stress disorder

  Among the thousands of people who volunteered their help in the hours following the terrorist attacks on the World Trade Center on 11 September 2001 were many doctors. What they experienced was so distressing that, when approached by researchers 18 months later, most preferred to keep their thoughts to themselves. A few, however, did agree to talk. Lynn de Lisi collected their accounts:

  One particular physician, a female psychiatrist … experienced survivor guilt, and [felt] that she needed to be doing more. At the time of the interview, she still felt somewhat removed from other people and irritable, and had upsetting reminders that lingered.

  Another physician said he drank twice as much alcohol after September 11 than before. He worked at a triage unit close to the World Trade Center site volunteering about 10 hours per day…. He stated that his worst memory was seeing people jump out of the towers.

  One physician was a staff psychiatrist on an inpatient unit who worked longer hours after the attacks. His alcohol intake increased after the attacks and at the time of the interview he still admitted to being preoccupied with painful images intruding on his thoughts. He still avoided participating in activities that would remind him of the events.

  But it wasn’t necessary to be directly involved for psychological problems to develop. Many Americans, even those living far from New York City, were profoundly shaken. Two months after 11 September, 17% of the 1,300 people contacted across the US in one survey reported associated post-traumatic stress symptoms. (Scale up that representative sample and you arrive at a total of 45 million people suffering serious psychological distress as a result of the attacks.) With the passing of time, the number of people reporting symptoms declined. Three years later, when 1,950 individuals were contacted by the same resear
chers, 4.5% were affected.

  Overall, the people most likely to develop problems were those who had:

  • personally witnessed the attacks;

  • watched live television coverage;

  • experienced traumatic events in their childhood, or after 11 September;

  • suffered previously from a psychological disorder.

  What is post-traumatic stress disorder?

  Given the magnitude of the horror inflicted upon New Yorkers on 11 September, it’s hardly surprising that many people – and especially those directly affected by the atrocity – subsequently developed severe psychological problems. But post-traumatic stress disorder (PTSD) is usually triggered by more commonplace disasters. The American Psychiatric Association’s Diagnostic and Statistical Manual (DSM) defines a traumatic event as one in which:

  the person experienced, witnessed, or was confronted with an event or events that involved actual or threatened death or serious injury, or a threat to the physical integrity of self or others.

  Examples of such trauma include serious traffic accidents, sexual assault, physical attack, violent robbery or mugging, the sudden death of a loved one, military combat, torture, natural disasters, and being diagnosed with a potentially fatal illness.

  PTSD is marked by three types of symptoms (that must persist for more than a month):

  • Reliving the traumatic event. This can take the form of nightmares or flashbacks, when the person feels that they are right back in the midst of the horror. Thoughts of the trauma constantly recur, no matter how doggedly the person tries to forget. Distressing memories can be sparked by the smallest things – perhaps a particular sound or smell, a place, or the look on someone’s face.

  • Avoiding any reminder of the traumatic event/feeling numb. The memory of the trauma is so upsetting that sufferers will go to any lengths to avoid triggering it. They try to suppress thoughts of the event; they steer clear of people and places that could remind them of what happened; and they don’t want to talk about their experiences. People with PTSD often report that they are emotionally ‘numb’ – at least to positive emotions like happiness. And they may try to deaden the anxiety and depression they feel by using alcohol or drugs. (Some experts argue that numbness is sufficiently different from avoidance to be regarded as a symptom category in its own right.)

  • Feeling constantly on edge. This is what psychologists call a state of hyperarousal, and it means being always anxious, irritable, and tense. People with PTSD are constantly on the alert for any reminder of the trauma: it dominates their world, day and night (sleep problems are a typical symptom of PTSD).

  As with all psychiatric diagnoses, however, many people may develop symptoms that aren’t sufficiently severe, persistent, or numerous to meet the official criteria, but which cause much distress nonetheless. And some researchers have questioned the DSM’s interpretation of what constitutes a trauma, suggesting that negative life events such as chronic illness, divorce, or unemployment can generate at least as many symptoms of PTSD as rape, assault, accidents, and so on.

  How common is PTSD?

  A reliable picture of the prevalence of PTSD is provided by the US National Comorbidity Survey (NCS), which found that roughly 50% of people experience at least one trauma in their lifetime, with 7.8% of the total sample developing PTSD. The figure is not dramatically different for young people. Of the 10,000 13- to 18-year-olds interviewed for the US National Comorbidity Survey Replication Adolescent Supplement, 5% reported having experienced PTSD, with 1.5% severely affected.

  Many types of trauma can trigger PTSD, but some are more potent than others. According to the NCS, the traumas most likely to result in PTSD in women were rape, sexual molestation, physical attack, being threatened with a weapon, and childhood physical abuse; and in men, rape, combat exposure, childhood neglect, and childhood physical abuse.

  Women in the NCS were twice as likely to develop PTSD as men, even though they experienced fewer traumas. This is only partly explained by the fact that women are more likely to experience the kinds of trauma that commonly produce PTSD (rape, for example). Exposed to the same type of trauma, women are more likely than men to develop PTSD – for reasons that are currently unknown.

  Research on PTSD in the developing world is scarce. But a team led by Joop de Jong investigated rates of the problem in four of the world’s poorest, most conflict-ridden countries: Algeria, where appalling violence erupted after elections were cancelled in 1991; Cambodia, which endured civil war in the 1960s and then the murderous regime of the Khmer Rouge; Ethiopia, also wracked by civil war; and Gaza, site of recurrent conflict since Israeli occupation in 1967. One would expect rates of PTSD in these troubled countries to be higher than in the West, and so it proved: 37.4% in Algeria (where violence was still occurring at the time of de Jong’s research); 28.4% in Cambodia; 15.8% in Ethiopia; and 17.8% in Gaza.

  No one received a diagnosis of PTSD until 1980, when it was included in the DSM for the first time. The psychological effects of combat had been acknowledged since the First World War, when huge numbers of soldiers developed ‘shell-shock’. But it took until the 1970s for PTSD to be recognized, largely through the efforts of Vietnam War veterans’ organizations – the Vietnam War having generated many thousands of cases – and those working with rape survivors. In 1990, it was estimated that more than a million US veterans had developed PTSD as a result of their experiences in Vietnam, with 479,000 still battling the disorder.

  What causes PTSD?

  Psychological perspectives

  In one sense, the cause of PTSD is obvious: a specific trauma. And yet this is only part of the explanation. Why is it that some people who are raped or badly beaten up develop PTSD and others do not?

  Of the psychological attempts to answer that question, arguably the most influential is the one formulated by Anke Ehlers and David Clark.

  The theory is nicely illustrated by a research study carried out by Ehlers and colleagues. For six months, they tracked the progress of 147 people who’d been injured in motor vehicle accidents. Two weeks after the accident, 33 (22.4%) met the criteria for a diagnosis of PTSD (except, of course, the stipulation that symptoms have lasted more than a month); six months later, 17 (12.1%) were affected.

  The individuals who developed PTSD tended to share certain characteristics:

  • Before the accident: a history of emotional problems and previous traumatic experiences.

  • During the accident: a focus on the sensations evoked by the trauma, rather than the meaning of what was happening (this is called ‘data-driven processing’); the feeling that the accident was happening to someone else (a lack of ‘self-referential thinking’); a sensation of detachment or numbness or that the accident wasn’t real.

  • After the accident: a pessimistic view of the trauma; an inability to clearly recall what had gone on; a perceived lack of support from friends and family; constant thoughts of the accident and its consequences or, conversely, avoidance of all reminders; adoption of safety behaviours (for instance, refusing to travel by car).

  Ehlers and Clark argue that PTSD arises when the person believes they are still seriously threatened in some way by the trauma they’ve experienced. Why should someone assume they are still endangered by an event that happened months or even years previously? Ehlers and Clark identify two factors.

  First is a negative interpretation of the trauma and the normal feelings that follow, for example:

  • Nowhere is safe.

  • I attract disaster.

  • I can’t cope with stress.

  • I’m going mad.

  • I’ll never be able to get over this.

  • No one is there for me.

  These interpretations can make the person feel in danger physically (the world seems fundamentally unsafe), or psychologically (their self-confidence and sense of wellbeing seem irreparably damaged).

  Second are problems with the memory of the trauma. Because
of the way the person reacts during the event, the memory somehow fails to acquire a properly developed context and meaning. As a result, it constantly intrudes, triggered automatically by the slightest reminder of the trauma (a colour, or smell, or vague physical resemblance). Ehlers and Clark liken the traumatic memory to:

  a cupboard in which many things have been thrown in quickly and in a disorganised fashion, so it is impossible to fully close the door and things fall out at unpredictable times.

  (In a related theory, Chris Brewin argues that PTSD develops when unconscious, situationally accessible memories (SAMs) of the trauma – which largely comprise sensory information – fail to be incorporated in conscious, verbally accessible memory (VAMs).)

  PTSD is maintained by exactly the kind of behaviours adopted by the individuals in the traffic accident study. Thus, cognitive therapy aims to persuade the person to drop these behaviours, and to tackle the negative beliefs and incomplete memories that provoke them.

  Biological perspectives

  PTSD seems to be marked by problems in the limbic system of the brain, and specifically the relationship between the: