It’s long been clear that sedentary behavior may be a risk factor for cognitive decline. But now, new research shows that not all sedentary behaviors are created equal when it comes to brain health.

In a new study published in The Journals of Gerontology, researchers at the University of South Australia compared how different sedentary activities affect cognitive function. They found that social or mentally stimulating activities such as reading or crafting were beneficial for memory and thinking abilities. Yet more passive activities like watching TV were detrimental.

The study’s results may have implications for dementia risk, study author Maddison Mellow, PhD, a postdoctoral research associate at the university’s Alliance for Research in Exercise, Nutrition and Activity, told Health. Though the study didn’t look at dementia outcomes, per se, she said cognitive function is a good measure for the potential progression of Alzheimer’s disease, which affects an estimated 6.7 million Americans. “In fact, for dementia such as Alzheimer’s disease, changes can start to happen in the brain over a decade before any cognitive changes appear,” she said. According to Mellow, previous research had already linked some sedentary behaviors, like reading or computer use, with improved cognitive function. “This means that to optimize 24-hour activity and sleep patterns for cognitive function, we may need to take a more nuanced approach and study the types of behaviors people are engaging in, rather than treating all sitting or active behaviors the same,” Mellow said.

Her team set out to do just that. They began with data from a large Australian study called ACTIVate, which included 397 dementia-free older adults aged 60 to 70. Participants completed questionnaires asking about the activities they engaged in for the previous two days. To see how activities impacted brain function, the researchers analyzed results from two tests: a paper-and-pencil-style screening tool that assesses five domains of cognitive function and a computer-based cognitive assessment.

When people engaged more in socializing, exercising, or doing “quiet time” activities like reading, listening to music, or religious practice, their scores increased. On the other hand, researchers found a link between lower scores and behaviors like watching TV or playing video games.

The study wasn’t without a few limitations, however. “The research predominantly relies on self-reported data regarding sedentary behaviors, which may be subject to biases or inaccuracies,” Hayley Nelson, PhD, a neuroscientist and founder of The Academy of Cognitive and Behavioral Neuroscience who was not affiliated with the study, told Health.

She also noted that the study’s design makes it difficult to establish a cause-and-effect relationship between physical activity, sedentary behavior, and cognitive function.