The personality trait of neuroticism is related to the tendency to develop negative thoughts in the face of stress. Efforts to research this link have been hampered by the fact that it is difficult to apply information gathered in lab-based questionnaires to 'real' life. A study of 279 pairs of twins in Belgium gave them wristwatches which beeped at random intervals throughout the day. When the watches beeped the twins filled out forms about their current thoughts, what they were doing, how they felt about the situation and their current mood. All the twins were female as it is thought that men and women react differently to stress. Those people with a twin who had suffered from depression at some point in their lives showed a stronger propensity for negative moods at times of stress. The link was stronger in identical than non-identical twins suggesting there may be a genetic component to this.
Wichers, Marieke ... [et al] - Genetic risk of depression and stress-induced negative affect in daily life British Journal of Psychiatry 191: 218-223
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