|Fig. 1: Search of Space (Source: Wikimedia Commons)|
After the dropping of the atomic bomb by the United States in Nagasaki, Japan during World War II,the effects of acute radiation exposure on health was closely monitored. Incidences of cancer and other predictable health concerns were methodically tracked. However, one facet of health that was not closely observed in atomic bomb survivors was mental health.
In one of the few health studies conducted immediately after the bombing which touched upon mental health, it was found that survivors exhibited signs of neurosis, the former name for a category of mental disorders characterized by anxiety and avoidance behavior. Patients exposed to high doses of radiation had a higher prevalence of neurosis than those that did not.  Though the incidences of certain kinds of cancers were reported to have increased in the early 1960's, the prevalence of psychosomatic conditions such as stomach and duodenal ulcers did not increase until later.  Retroactive examination of health surveys taken from 1962 - 1965 found that survivors exposed to acute levels of radiation were twice as likely to exhibit anxiety and somatization symptoms, displays of physical symptoms which have no physical cause.  These findings are in keeping with Deering's hypothesis, a post-war study suggesting that trauma involving physical suffering is more likely to lead to somatization than those without.  While those suffering from acute radiation sickness showed higher incidences of anxiety and somatization symptoms overall, proximally exposed people also exhibited such symptoms with increasing prevalence growing radially outward from the hypocenter. 
New data gathered more than 50 years post-bombing finds prolonged mental distress in both exposed and non-exposed people. Individuals who experienced the bombing demonstrated higher levels of overall psychological disturbance than those who didn't, with a greater prevalence than concluded by previous studies. Distress was most strongly related to social activity - apathy, disrupted personal relationships, loss of pleasantness of living - suggesting that witnessing the bombing continues to have an impact on the daily life of survivors even half a century later. Exposed individuals, however, showed lower incidences of anxiety and depression relative to a control group, a significantly different finding than previous studies from earlier dates.  Even those who were in Nagasaki but outside the blast radius and experienced no measurable amount of radiation exhibit signs of mental disturbance. Despite having no physical markings of exposure, individuals who experienced the blast even peripherally had markedly higher chances of possessing psychological disorders relative to the control group. This anxiety is believed to stem from a fear of learning of nuclear hazard and lack of knowledge concerning radiation risk. 
Although the data concerning the mental health of atomic bomb survivors is intermittent and discontinuous, analysis of mental health studies from then and now suggest that the experience of the nuclear explosion in Nagasaki, even peripherally, can have profound psychological effects. Furthermore research suggests that these effects are evolving and nonlinear, ranging from varying experiences of neurosis, psychosomatic symptoms, social withdrawal, anxiety, and depression over time. Finally, within the umbrella term of "atomic bomb survivors", there are a number of ways in which group members can be further fragmented and studied such as by exposure levels (those who experienced acute radiation, those who were minimally exposed, and those who experienced no radiation whatsoever) or age. Such studies may provide new insights into the long-term implications of experiencing an event as physically and emotionally catastrophic as nuclear war.
© Dana Yeo. The author grants permission to copy, distribute and display this work in unaltered form, with attribution to the author, for noncommercial purposes only. All other rights, including commercial rights, are reserved to the author.
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