Memory bias in obsessive-compulsive disorder (OCD).

There is a memory bias associated with depression, and good reason to expect a memory bias associated with anxiety. However, the results of studies reported to date have been ambiguous. Accordingly, an experiment was conducted to assess memory for contamination in people with different types of anxiety. Memory for contaminated stimuli among participants who met DSM-IV criteria for obsessive-compulsive disorder (OCD) and indicated a fear of contamination (n = 10) was compared to memory in a group of anxious controls (n = 10), and in undergraduate students (n = 20). Participants were shown 50 objects, 25 of which were contaminated by the experimenter and 25 which were touched but not contaminated. They then completed a neuropsychological memory assessment, after which the participants were asked to recall all of the objects touched by the experimenter. They were then asked to approach each object and to rate their anxiety about touching it. Finally, participants were asked about their perceptions of the cleanliness of each object. The OCD group had better memory for contaminated objects than for clean ones. Neither control group showed such a bias. Neuropsychological test scores indicated that this bias is not the result of differences in general memory ability. The results are discussed in terms of the memory-deficit theory of OCD and of behavioural and cognitive approaches to understanding the role of information processing in fear and anxiety.     

Spontaneous decay of compulsive urges: Cumulative effects

In a laboratory investigation of compulsive urges (and the associated discomfort) it was confirmed that these phenomena are subject to spontaneously-occurring decrements. These decrements take place within 15–180 min, according to variations in the experimental conditions. The declines in urges and discomfort follow parallel courses. With repetition, the declines in urges and discomfort take place more rapidly. The decremental effects are cumulative and stable. The spontaneous decay curve shrinks with repeated trials.     

Unprepared phobias: "be prepared".

The weaknesses of the equipotentiality premise are rehearsed and an alternative theory of preparedness, with particular reference to phobias, is outlined. Two clinical cases which appear to be contrary to prediction are described. Although their phobias were unprepared (lack of biological significance, rarity, and probably gradual acquisition) they showed features (high resistance and broad generalization) not predicted by the theory. It is suggested that these features may appear as a result of (i) overlearning. (ii) symbolic transformation or (iii) considerable associated psychopathology.     

Does escape behaviour strengthen agoraphobic avoidance? A preliminary study

Two groups of agoraphobic patients were treated with one of two forms of exposure-based therapy. In one group, the patients stayed in the target situation until their self-rated anxiety dropped by half (Endurance condition). In the other, the patients were required to leave the fear situation when their anxiety reached a high pre-set level, without waiting for anxiety to drop (Escape condition). The patients in both groups improved, in contrast to those in a Waiting-list control group. There were no significant differences between the two treated groups. The results are discussed in terms of Mowrer's theory of fear and avoidance from which it can be predicted that patients in an ‘escape condition’ should not improve. Contrary to a Mowrerian prediction, patients who were taught to escape when still fearful, did not show increased avoidance behaviour.     

Exposure and fear-reduction

Boyd and Levis (1983, this issue, pp. 143–149) have contested the main argument of our earlier paper on exposure and fear-reduction (de Silva and Rachman, 1981). In this reply, our original argument is briefly restated and the position explained. Boyd and Levis' argument that exposure is necessary, is critically examined and it is concluded that the search for alternative (and additional) explanations of fear-reduction is a valid and useful exercise. Further investigations of the mechanisms of exposure and of non-exposure methods, are warranted.     

Prepared phobias and obsessions: Therapeutic outcome

Sixty-nine phobic and eighty-two obsessional patients, treated at the Maudsley Hospital, were rated for ‘preparedness’, the evolutionary significance of the content and behaviour of the disorder. Reliable ratings (r = 0.78 and 0.90) of the dangerousness of the object or situation to pretechnological man indicated that the content of the large majority of the phobias and obsessions are judged as evolutionarily significant. Degree of preparedness, however, did not predict outcome of therapy, suddenness of onset of the disorder, severity of impairment, intensiveness of the treatment received, or age of onset. Nor was there any significant relationship between preparedness and certain other variables in the obsessional sample: stimulus generalization, effect on life style, impaired reproductive capacity and abnormal personality. The implications of these findings for the hypothesis that human phobias and obsessions are prepared, and for the clinical usefulness of the concept of preparedness, are discussed.