Ellett Lyn, Freeman Daniel, Garety Philippa A
Department of Psychology, Institute of Psychiatry, King's College London, University of London, UK.
Schizophr Res. 2008 Feb;99(1-3):77-84. doi: 10.1016/j.schres.2007.10.027. Epub 2007 Dec 3.
Epidemiological studies have found that individuals who live in urban areas are at increased risk of developing psychosis. However it is unknown whether exposure to urban environments exacerbates psychotic symptoms in people who have a diagnosed psychotic disorder. The aim of the study was to examine the psychological and clinical effects of exposure to one specific deprived urban environment on individuals with persecutory delusions. It was predicted that the urban environment would affect emotional and reasoning processes highlighted in a cognitive model of persecutory delusions and would increase paranoia.
Thirty patients with persecutory delusions were randomised to exposure to a deprived urban environment or to a brief mindfulness relaxation task. After exposure, assessments of symptoms, reasoning, and affective processes were taken. Thirty matched non-clinical participants also completed the study measures to enable interpretation of the test scores.
In individuals with persecutory delusions, exposure to the urban environment, rather than participation in a mindfulness task, increased levels of anxiety, negative beliefs about others and jumping to conclusions. It also increased paranoia. The individuals with persecutory delusions scored significantly differently from the non-clinical group on all measures.
For individuals with psychosis, spending time in an urban environment makes them think more negatively about other people and increases anxiety and the jumping to conclusions reasoning bias. Their paranoia is also increased. A number of processes hypothesised in cognitive models to lead to paranoid thoughts are exacerbated by a deprived urban environment. Further research is needed to clarify which aspects of urban environments cause the negative effects. Methodological challenges in the research area are raised.
流行病学研究发现，生活在城市地区的个体患精神病的风险增加。然而，尚不清楚暴露于城市环境是否会加重已确诊患有精神障碍的人的精神病症状。本研究的目的是考察暴露于一种特定的贫困城市环境对患有被害妄想症的个体产生的心理和临床影响。研究预测，城市环境会影响被害妄想症认知模型中所强调的情绪和推理过程，并会增加偏执狂症状。
30名患有被害妄想症的患者被随机分为两组，一组暴露于贫困城市环境，另一组进行简短的正念放松任务。暴露后，对症状、推理和情感过程进行评估。30名匹配的非临床参与者也完成了研究测量，以便对测试分数进行解读。
在患有被害妄想症的个体中，暴露于城市环境而非参与正念任务，会增加焦虑水平、对他人的负面信念以及草率下结论的情况。这也会增加偏执狂症状。在所有测量指标上，患有被害妄想症的个体得分与非临床组有显著差异。
对于患有精神病的个体而言，在城市环境中停留会使他们对他人的看法更消极，增加焦虑和草率下结论的推理偏差。他们的偏执狂症状也会增加。认知模型中假设的一些导致偏执想法的过程会因贫困城市环境而加剧。需要进一步研究以阐明城市环境的哪些方面会造成这些负面影响。同时也提出了该研究领域的方法学挑战。
