People who experience trauma in child- and adulthood may experience a greater amount of cognitive decline as they age than individuals who haven’t experienced trauma, a new study found.
The research also showed that recent trauma in adulthood has a larger impact on some aspects of cognitive functioning than trauma in childhood.
“We found that the more adverse events experienced, such as your parents’ divorce or a parent dying, the greater the cognitive decline,” says coauthor Margie Lachman, professor of psychology at Brandeis University.
The researchers studied roughly 2,500 adults, ages 28 to 84, between 2004 and 2013. The participants were part of the Midlife Development in the US (MIDUS) study, a national longitudinal study of health and well-being in adulthood.
Participants were given a list of 12 potentially traumatic events and asked if they’d experienced any, and how negatively they were affected.
The events on the list included divorce or death of a parent during childhood, emotional or physical abuse , parental alcohol or drug addiction, combat experience , and losing a home to fire, flood, or natural disaster. For any of these to be considered traumatic, respondents needed to indicate they caused severe emotional distress.
Researchers also asked subjects a series of questions that tested their cognitive abilities in two areas: executive functioning (EF) and episodic memory (EM). EF pertains to such skills as focusing attention, planning, problem-solving, and multitasking. The test of EM involved remembering recently learned information.
The scientists compared the results of individuals who says they had lived through trauma with those who indicated they hadn’t and tested their EM and EF over the course of nine years.
Those respondents who says they had experienced more traumatic events showed greater declines in both EF and EM.
Lachman says this may be because trauma has been linked to stress and depression , both of which are known to impair cognitive functioning.
Trauma is also linked to metabolic disease, inflammation, and disruption of the body’s immune system, which are likewise also known to harm the brain’s performance.
Lynch stresses that trauma does not automatically mean an individual will experience greater cognitive impairment in later life. The impact of trauma varies and some people are more resilient or receive treatment that can mitigate the effects.
Lynch, who is now a PhD student at the John Jay College of Criminal Justice in New York, also says the effects of cognitive decline can be subtle and may go unnoticed.
“It might not feel like there’s an effect on your day-to-day functioning,” she says.
The researchers also looked at whether childhood or more recent traumatic experiences had a greater effect on cognition. They found that individuals exposed to trauma later in life had a greater decline in EF than individuals whose first traumatic event occurred earlier in life. The amount of decline in EM did not vary based on when the event occurred in life, a finding that the researchers says required further study.
Lachman speculates there may be more of an opportunity to recover from trauma that occurs years before, in childhood. She says children may be more likely to receive supportive interventions or the increased plasticity of their brains may make them more likely to adapt in the long term.
The research appears in the Journal of Traumatic Stress .