How Stress Knocks Out Your Cognitive Reserve

Researchers in the late 1980s discovered that some individuals who showed no apparent symptoms of dementia during their lifetime had brain changes consistent with advanced Alzheimer’s disease. This led to the hypothesis of cognitive reserve, which might provide a protective effect against dementia. Cognitive reserve is built through cognitively stimulating and enriching life experiences and behaviors such as higher educational attainment, complex jobs, continued physical and leisure activities, and healthy social interactions.

However, high or persistent stress levels are linked to reduced social interactions, impaired ability to engage in leisure and physical activities, and an increased risk of dementia. Researchers from Karolinska Institutet have examined the association between cognitive reserve, cognition, and biomarkers for Alzheimer’s disease in 113 participants from the memory clinic at Karolinska University Hospital in Huddinge, Sweden. They also looked at how this association is modified by physiological stress (cortisol levels in saliva) and psychological (perceived) stress.

The study found that greater cognitive reserve improved cognition, but physiological stress appeared to weaken this association. According to the study’s lead author, Manasa Shanta Yerramalla, mindfulness exercises and meditation may reduce cortisol levels and improve cognition, suggesting that stress management strategies could complement existing lifestyle interventions for Alzheimer’s prevention.

Despite the relatively small sample size, the results are generalizable to similar patient groups. The researchers controlled for sleeping medications but did not consider other aspects of sleep that might impair cognition, acknowledging that stress disrupts sleep, which in turn affects cognition. Dr. Yerramalla stated that they will continue to study the association between stress, sleeping disorders, and cognitive reserve in memory clinic patients.

In summary, the study highlights the importance of cognitive reserve in protecting against dementia and the negative impact of stress on this relationship. It suggests that integrating stress management strategies with lifestyle interventions could enhance Alzheimer’s prevention efforts.

Story Source: Materials provided by Karolinska Institutet. Content may be edited for style and length.