CLINICAL HANDBOOK OF SCHIZOPHRENIA

78 I. CORE SCIENCE AND BACKGROUND INFORMATIONarousal is far from universal, and content is necessary for the diagnosis of several anxietydisorders—specific phobias, agoraphobia, and social phobia. When people become anxiousthey have already begun to think differently, and this is sometimes in relation to socialcircumstances. It is perhaps via this route that the specific relationships betweenstressful events, stressful situations, and schizophrenia may be found.The links between social phobia and paranoia are of particular interest. Why aresome people anxious about the demands of social interaction, attributing their physicalstate to their own inadequacies (social anxiety), whereas others attribute their anxiety tothe machinations of others (paranoia)? Researchers have begun to explore this issue innonclinical and prodromal samples using virtual reality inhabited by computer-generatedcharacters called avatars. The use of a virtual reality scenario with avatars (a library scenewas used in one study) allows for control of the environment, while still eliciting realisticemotional reactions (as TV shows such as The Simpsons are able to do). We have foundthat such situations, which by definition are not threatening, can elicit paranoid reactionsin some participants.Another aspect of cognition that relates to the experience of social stress is selfesteem,which is very frequently diminished in people with schizophrenia. Moreover, theyare very likely to have experienced events that virtually guaranteed diminution of theirself-esteem. The work described earlier linking intrusive events specifically to schizophreniais a further example of how the characteristics of events, in terms of their capacity toarouse particular patterns of thought, may account for their capacity to elicit responseswith the typical features of schizophrenia, such as persecutory ideas.Although it remains likely that some of the specificity of a schizophrenia response inmany people lies in processes determined outside the person/social–environmental interaction,it is difficult to be sure. Social anxiety and paranoia are also distinguished becausepeople prone to paranoia have a greater capacity for anomalous experiences. Is thiscapacity wired into the brain as a result of genetic and other biological processes? It ispossible, but it may equally be caused by the impact of particular types of stress. For example,severe traumatic events can also elicit or exaggerate the likelihood of experiencingsubsequent intrusive thoughts.In conclusion, there is now good evidence that stressful events and circumstancesform part of the causal nexus for the emergence of schizophrenia. A history of such experiencesis not apparent in everyone with schizophrenia, but neither is a family history ofthe disorder. It seems likely that schizophrenia is caused by a range of influences, none ofwhich is either necessary or sufficient in the individual case. These social influences thenalso operate to impede recovery.MECHANISMSAlthough we have discovered these relationships, we have not yet disentangled the specificmechanisms or how they may perhaps interact to cause initial episodes and relapses.We have made some progress with models of vulnerability, probably genetic, but also,plausibly, brought on by early adverse environments, such as emotional neglect, isolation,or specific trauma. Later, triggered by stresses such as negative life events or negative relationships,individuals may experience an increasing cascade of cognitive and perceptualanomalies that, together with emotional reactions, lead them to conclude not that this is a“bad day,” but that external agents are conspiring against them (i.e., paranoia). Oncetriggered, recovery from such an episode also depends on a wide range of cognitive, emotional,and social factors, and their interaction determines outcome and future course.