Several explanations, not mutually exclusive, may explain the altered pain sensitivity and ineffectiveness of sucrose as an analgesic among PDEP children. First, the lower pain tolerance may be due to difficulties in attending to the task. This seems unlikely, because PDEP children did not have difficulty in performing other study-related tasks, and those who reported having attention problems had pain thresholds and tolerance similar to those of the other children. Secondly, PDEP children may experience more emotional stress and increased affective processing both before and during experience with painful stimuli [65,66]. Perhaps the initial emotional hyperreactivity impaired their ability to modulate the pain experienced when their hand was submersed in the cold water [65]. Although we do not have measures of how often the children in the present study experienced pain, there are reports that depressed children complain about abdominal pain [67] and headaches [68] more often than do other children. The co-occurrence of depression and chronic pain in adults has been associated with greater pain-evoked neuronal activation in brain regions associated with affective pain processing [69], which may in
