Silent brain infarcts, small areas of brain tissue damage that can occur without obvious stroke symptoms, were associated with about twice the odds of executive dysfunction in a study of community-dwelling older adults in Japan.
The findings suggest that vascular brain injury may be detectable through difficulties with cognitive control even among older people who remain independent in daily life and have no apparent dementia. The study does not establish that silent infarcts caused the cognitive differences, but it strengthens evidence connecting cerebral small vessel disease with executive function.
What the researchers studied
Researchers conducted a cross-sectional observational study in the neighbouring rural communities of Sefuri and Yoshinogari in Saga, Japan. Data were collected between 2010 and 2021.
The final analysis included 652 adults aged 58 to 94 years who were living independently and had no apparent dementia. Their mean age was 69.7 years and their average educational attainment was 12.2 years. The sample included 280 men and 372 women.
Participants underwent cognitive testing and brain magnetic resonance imaging. Global cognitive function was assessed using either the Mini-Mental State Examination or Montreal Cognitive Assessment. Executive function was assessed with a modified Stroop test, which requires participants to suppress an automatic response and follow a conflicting instruction. The researchers also measured apathy.
Brain imaging was performed using a 1.5 tesla MRI scanner. The researchers assessed silent brain infarction, deep white matter lesions and hippocampal atrophy. Silent brain infarcts were defined using multiple MRI sequences and had a diameter of at least 3 millimetres.
Silent infarcts were present in one in ten participants
The MRI scans identified 124 silent infarcts in 65 of the 652 participants, meaning 10.0% of the study population had at least one silent brain infarct. The lesions occurred most often in the basal ganglia, where 72 infarcts were detected. A further 32 were located in the corona radiata and 11 in the thalamus, with smaller numbers in the cerebellum and brain stem.
Deep white matter lesions were more common, appearing in 261 participants, or 40.0% of the sample. Most were relatively mild grade 1 lesions.
Depending on the age-adjusted definition used, executive dysfunction was identified in 65 participants, or 10.0%, under the researchers’ first model and 125 participants, or 19.2%, under the second model.
Silent infarcts were associated with executive dysfunction
After accounting for age, education and vascular risk factors, silent brain infarction was associated with significantly higher odds of executive dysfunction under both definitions used by the researchers.
In the first model, participants with silent brain infarction had 2.392 times the odds of executive dysfunction compared with those without it, with a 95% confidence interval from 1.215 to 4.708. In the second model, the odds ratio was 2.040, with a 95% confidence interval from 1.157 to 3.598.
A sensitivity analysis that excluded isolated cerebellar or brain-stem infarcts produced essentially the same pattern. The number of silent infarcts in the whole brain, thalamus and corona radiata was also significantly associated with executive dysfunction.
The pattern differed for broader cognitive screening. Cognitive dysfunction measured by the Mini-Mental State Examination was associated with hippocampal atrophy, with an odds ratio of 1.950. For the Montreal Cognitive Assessment, hippocampal atrophy was associated with cognitive dysfunction at an odds ratio of 2.603, while silent brain infarction was also associated at an odds ratio of 2.028.
Why executive function matters
Executive function covers mental processes used to control behaviour, switch between tasks, manage competing information and inhibit automatic responses. These abilities can be affected by vascular cognitive impairment, which is cognitive impairment associated with cerebrovascular disease.
The study’s results support a distinction between cognitive patterns associated with different forms of brain pathology. Performance on broad cognitive screening tests was primarily associated with hippocampal atrophy, while poorer performance on the modified Stroop test was independently associated with silent brain infarction.
This distinction may be clinically relevant because silent infarcts can occur without the symptoms normally associated with stroke. A person may therefore have vascular brain injury while remaining independent and without a history of clinically recognised stroke.
Apathy did not independently explain the association
The researchers also examined whether apathy could help explain poorer executive performance. Modified Stroop scores showed a small association with the apathy measure in unadjusted analysis, but apathy was not independently associated with executive dysfunction once potential confounding factors were considered.
Education was associated with both executive function and apathy, illustrating why adjustment for demographic factors was important when interpreting the relationship.
What the findings could mean
The results add to evidence that cerebral small vessel disease may affect cognition before dementia becomes apparent. They also suggest that tests of executive control may capture aspects of vascular cognitive impairment that are not identical to the deficits reflected by general cognitive screening.
The researchers note that vascular risk factors, particularly hypertension, are important risk factors for silent brain infarction and cerebral small vessel disease. This raises the possibility that preventing vascular injury through better risk-factor control could also contribute to preserving cognitive health, although the present study did not test an intervention or demonstrate that risk-factor treatment prevents executive decline.
Important limitations
The cross-sectional design is the most important limitation. Brain imaging and cognitive performance were assessed within the same observational framework, so the study cannot establish that silent infarcts caused later executive decline.
The participants were volunteers from two rural Japanese communities rather than a random population sample, which may limit how well the findings generalise to other populations. Only 65 participants had silent brain infarction, leaving a comparatively small exposed group despite the overall sample of 652.
The authors also noted that the effect of silent infarction on executive function appeared smaller than the effect of age. Executive dysfunction was assessed using a single modified Stroop test, so the study did not capture every component of executive functioning. These findings should therefore be interpreted as an association between MRI-detected vascular injury and one measured aspect of cognitive control, not as evidence that every silent infarct produces noticeable cognitive impairment.
Source Information
Study: Silent brain infarction is associated with executive dysfunction in community-dwelling older adults: the Sefuri-Yoshinogari study
Authors: Hiroshi Yao, Kenji Fukuda, Manabu Hashimoto, Yasushi Okada and colleagues
Journal: Hypertension Research
Published: 25 September 2026
DOI: 10.1038/s41440-026-02811-5
