Working Memory Worse in Type 2 Diabetes

Working Memory Worse in Type 2 Diabetes
Working Memory Worse in Type 2 Diabetes
Patients with type 2 diabetes demonstrated worse executive and working memory, which may be relevant to their risk for Alzheimer's disease.

Patients with type 2 diabetes exhibited worse executive function and working memory and also demonstrated decreased activation in certain areas of the brain than those without the condition, according to new research published in Diabetes Care.

These findings, the researchers wrote, may offer insight into the mechanisms behind diabetes-related cognitive impairment.

“Type 2 diabetes mellitus has important effects on cognition and the risk for Alzheimer disease. Working memory is a susceptible cognitive domain of mild cognitive impairment and [Alzheimer disease]. Thus, the identification of brain activation patterns under different [working memory] loads can potentially enhance our understanding of the mechanisms underlying cognitive dysfunction in [type 2 diabetes],” they wrote.

To learn more, the researchers evaluated 30 patients with type 2 diabetes (mean age, 63.67 years) and 37 healthy controls (mean age, 64.22 years) from the ongoing, longitudinal Beijing Aging Brain Rejuvenation Initiative (BARBI) study.

Participants underwent a battery of neuropsychological tests designed to assess general mental status and other cognitive domains, including memory, attention, spatial processing, executive function and language abilities.

Results indicated that patients with diabetes, as compared with those without the condition, performed significantly worse on the working memory tasks (backward digit span, P=.027 and digit span, P=.05) and executive function task (Stroop Color and Word Test-B-C, P=.045).

The researchers also found differences in patterns of brain activation under different working memory loads. Specifically, patients with type 2 diabetes had less activation in the left inferior frontal gyrus under low loads and less activation in the left middle frontal gyrus and superior frontal gyrus under high loads, according to the data.

“Thus, more regions of diminished activation were seen in the frontal cortex with increasing task difficulty. Furthermore, we found that lower [superior frontal gyrus] activation was associated with worse cognitive function,” they wrote.

The researchers concluded that this was the first study to identify specific brain mechanisms associated with working memory dysfunction related to diabetes and represents a step toward advancing clinicians’ knowledge about the correlation between diabetes and cognitive impairment.

“This study provides evidence about the neural mechanisms that underlie cognitive impairment in [type 2 diabetes] and may lead to establishing potential imaging-based biomarkers for the prevention and early treatment of cognitive dysfunction caused by [type 2 diabetes],” they wrote.

The researchers, however, cautioned that more longitudinal studies are necessary to both confirm their findings as well as assess the value of brain imaging in predicting disease progress in these patients.


  1. Chen Y et al. Diabetes Care. 2014;37:3157-3163.