Polygenic scores for executive functioning as predictors of performance improvements after repeated testing in major psychiatric disorders

Why your brain gets better at tests

When we take the same memory or attention test several times, scores usually go up simply because we get used to the tasks. For people living with major psychiatric disorders, these “practice effects” can be weaker, and doctors sometimes use that lack of improvement as an early warning sign for dementia. This study asks a deeper question: are these test gains partly written into our DNA, and do they matter for people with depression, bipolar disorder, or psychotic illnesses such as schizophrenia?

Thinking skills as the brain’s control center

The researchers focused on “executive functions” — the mental control skills that help us plan, stay flexible, hold information in mind, and resist distractions. Instead of looking at each paper-and-pencil test on its own, they built a single hidden score that captured what all five different tests had in common. This combined score reflects a person’s overall ability to manage complex mental tasks, beyond any one specific game-like challenge. By tracking this shared measure over time, they could see clearer patterns of change than by looking at any single test.

A long look at many minds

The team drew on the PsyCourse study, which has followed more than 1,500 adults in Germany and Austria. Participants included people with major depression or bipolar disorder, people with psychotic disorders such as schizophrenia, and volunteers without psychiatric diagnoses. Everyone completed the same set of thinking tests up to four times over 18 months, and they also provided genetic samples. Using results from huge international genetic studies, the authors calculated two types of “polygenic scores” for each person: one reflecting a genetic tendency toward stronger executive functions, and another reflecting general vulnerability to psychiatric problems across diagnoses.

Genes that favor mental control

Across the whole group, test performance on the combined thinking-skill score steadily improved with each visit, showing robust practice effects. People without psychiatric diagnoses started higher and stayed ahead, while those with affective disorders did moderately well and those with psychotic disorders showed the lowest scores and smaller gains. Importantly, individuals whose DNA carried more variants linked to better executive function tended to show stronger improvements over time on the overall combined score. In other words, their genetic makeup seemed to support better use of practice, regardless of whether they had a psychiatric diagnosis. By contrast, the broad genetic tendency toward psychiatric illness did not predict who improved more with repeated testing.

Hidden patterns, not single test wins

The genetic signal only emerged when the researchers looked at the shared, “under-the-surface” executive-function score. When they examined each of the five tests separately, genetic makeup did not reliably predict who would improve more. This suggests that any single test is too noisy and tangled with other skills, such as motor speed or vision, to cleanly reflect the influence of genes on practice effects. By combining information across tests into one latent score, the study reduced this noise and revealed how many tiny genetic influences can add up to shape the brain’s capacity to benefit from repetition.

What this means for patients and clinicians

For a layperson, the take-home message is that some people are genetically inclined to squeeze more benefit out of repeated mental testing than others, and this holds true even in the context of serious psychiatric disorders. However, the effects are modest and only visible when we look at thinking skills in a broad, integrated way, not test by test. In the future, combining genetic information with detailed cognitive profiles could help doctors interpret changes in test scores more accurately—for example, distinguishing between someone who fails to improve because of disease progression and someone whose genetics simply offer less boost from practice. The work is an early step, and larger, more diverse studies will be needed before such insights can guide everyday care.

Citation: Navarro-Flores, A., Heilbronner, M., Rafiee, H. et al. Polygenic scores for executive functioning as predictors of performance improvements after repeated testing in major psychiatric disorders. Sci Rep 16, 9199 (2026). https://doi.org/10.1038/s41598-026-41345-1

Keywords: executive function, polygenic scores, practice effects, psychiatric disorders, cognitive testing