Trauma suffered both in childhood and adulthood may lead to significant cognitive decline later in life, according to a new study that highlights the importance of therapy and other interventions in order to stave off mental health problems.

“We found that the more adverse events experienced, such as your parents’ divorce or a parent dying, the greater the cognitive decline,” said Margie Lachman, professor of psychology at Brandeis University and co-author of the new study.

It’s no secret that traumatic stress can provoke long-lasting changes in key brain areas involved in stress response, such as the amygdala, hippocampus, and prefrontal cortex.

Previously, neuroscientists found that patients with post-traumatic stress disorder (PTSD) had smaller hippocampal and anterior cingulate volumes, increased amygdala function, and decreased medial prefrontal/anterior cingulate function. In addition, patients with PTSD show increased cortisol and norepinephrine responses to stress.

In terms of behavior and symptoms, PTSD is strongly associated with disruptions in one’s ability to have healthy, satisfying relationships and a low tolerance for uncertainty and adversity.

In their new study, Lachman and graduate student Kristin Lynch investigated potential associations between trauma and cognition.

The researchers combed through the Midlife Development in the U.S. (MIDUS) study, a national longitudinal study of health and well-being in adulthood, which involved 2,500 adults, ages 28 to 84.

The participants had to complete a questionnaire that listed 12 potentially traumatic events and investigated how these events negatively affected them. Examples of potentially traumatic events include divorce or death of a parent during childhood, emotional or physical abuse, parental alcohol or drug addiction, military combat experience, and losing a home to fire, flood, or natural disaster.

Each subject also had to complete tests that assessed their cognitive abilities in two key areas: executive functioning (focusing attention, planning, problem-solving, and multitasking) and episodic memory (remembering recently learned information).

The cognitive test results were compared to those from participants who claimed they hadn’t experienced traumatic events.

Not surprisingly, those who said they experienced trauma in the past exhibited a greater decline in both executive functioning and episodic memory.

The researchers also found that exposure to trauma later in life led to a greater decline in executive functioning than those who suffered from childhood trauma. There were no significant differences in episodic memory decline between those who experienced trauma earlier or later in life.

According to the researchers, trauma may lead to impaired cognitive performance due to the effects of stress and depression. Trauma is also linked to metabolic disease, inflammation, and disruption of the body’s immune system, which are also known to harm the brain’s performance.

The researchers stress that the effects of trauma on the brain vary on a person-to-person basis and for some they can be quite subtle. “It might not feel like there’s an effect on your day-to-day functioning,” Lynch said.

The findings appeared in the Journal of Traumatic Stress.