A new study has observed that teens with slower performance on a test of “cognitive processing speed” are more likely to have depression and anxiety symptoms as adults.
According to the new research by Catharine R. Gale, PhD, of Edinburgh University and colleagues, adolescents with slower processing speed may be at increased later risk of anxiety and depression and the results add new evidence that lower cognitive ability may be a contributor to depression, rather than a consequence of it.
The researchers analyzed data from 705 Scottish participants in a study including follow-up from adolescence into adulthood. At age 16, the participants were evaluated on a simple test of cognitive processing speed reaction time in pressing keys corresponding to numbers (1 to 4) flashed on a screen.
Slower cognitive processing speed that is, longer reaction time at age 16 was associated with increased anxiety and depression symptoms at age 36 and after adjustment, the relationship remained significant for one of the two mental health questionnaires (the General Health Questionnaire), but not the other (the Hospital Anxiety and Depression Scale).
The researchers were also interested in assessing the role of the cumulative effects of stress over time, or “allostatic load.” As reflected by various measures related to stress-for example, blood pressure and general inflammation-allostatic load seemed to at least partly account for the link between reaction time and anxiety/depression symptoms. However, this relationship was no longer significant after adjustment for other factors.
The study is published in official journal of the American Psychosomatic Society.