Researchers have been interested in the impact that a person's positive affect could have, i.e. the subjective experience of pleasant affective states such as enthusiasm or joy over longer or shorter intervals of time, on the decline in memory in midlife. They claim that this state of mind works well in favor of good cognitive health in the years that follow.


The decline in memory is a concern for aging populations around the world. Numerous studies have shown that there are factors that can reduce or even prevent it, including physical and cognitive activity. In a recent study published in the journal Psychological Science, researchers at Northwestern University looked at associations between positive affect (that is, feeling enthusiastic, attentive, active) and related memory decline. with aging. These start from the observation that many physical and emotional factors can have a negative impact on our ability to retain information throughout life.

 Their study found that people who feel enthusiastic and upbeat, a concept psychologists call "positive affect," are less likely to experience memory decline as they age. According to its authors, “this finding adds to a growing body of research on the role of positive affect in healthy aging. To come to this conclusion, they analyzed data from 991 middle-aged American adults and senior citizens who participated in a national wellness study called MIDUS (for "Midlife in the United States") conducted in three different periods: between 1995 and 1996, between 2004 and 2006, and between 2013 and 2014.

"Lower memory decline over nearly a decade"

In each evaluation, the participants were asked how many times over the last 30 days, they had felt positive emotions (enthusiastic, proud, attentive ...). Their responses were rated on a scale from 1 (never) to 5 (all the time) to rate their positive affect. In the last two assessments, they also performed memory tests that consisted of recalling words immediately after their presentation and 15 minutes later. Taking into account factors such as age, gender, and education, the researchers examined the association between positive affect and memory decline, specifically "immediate" and "delayed" memory.

The results revealed that positive affect was associated with less memory decline in mid- and late-life. “Our results showed that memory decreases with age. However, people with higher levels of positive affect experienced less pronounced memory loss over the course of nearly a decade. », Conclude the researchers. They also found that memory declines more in individuals with low positive affect compared to those with high positive affect. The next step in their study is to find out what mechanisms link positive affect to memory, such as physical health or social relationships.

They hope that their discovery will interest scientists and not just those specializing in the field of cognitive science. Indeed, age-related cognitive decline may be linked to simple brain aging or may be the harbinger of neurodegenerative disease, such as Alzheimer's disease and other related diseases. It therefore represents a rapidly growing public health problem for all countries around the world. As the World Health Organization (WHO) explains on this subject, nearly 10 million new cases of dementia are recorded each year and this number is expected to triple by 2050.