The age at which people typically start to have problems remembering details.
People typically begin to have difficulties remembering details — like where they left the keys — in their 40s.
The cause, though, could be less about a decline in brain function, and more about a change in the way memories are formed and retrieved.
Research shows that older adults focus more on what is relevant to them, rather than paying attention to external details.
Focusing on external details could help promote healthy cognitive aging.
Dr Natasha Rajah, one of the study’s authors, said:
“This change in memory strategy with age may have detrimental effects on day-to-day functions that place emphasis on memory for details such as where you parked your car or when you took your prescriptions.”
People aged 19 to 76-years-old were shown a series of faces and had to recall where they appeared on the screen, while their brains were scanned.
The results showed that younger people really paid attention, with their visual cortices running on overdrive, Dr Rajah said:
“They are really paying attention to the perceptual details in order to make that decision.”
Older people, though, showed lower activation in the visual cortex.
Instead, their medial prefrontal cortices were more active.
This area is related to introspection and aspects of one’s own life.
Younger people performed better on the task — but the reason may be because of what older people choose to focus on.
Dr Rajah said:
“This may not be a ‘deficit’ in brain function per se, but reflects changes in what adults deem ‘important information’ as they age.”
Older people can learn to improve their memory by focusing on external details rather than internal information, Dr Rajah said:
“That may be why some research has suggested that mindfulness meditation is related to better cognitive aging.”
Hormonal influences are currently being tested as another explanation:
“At mid-life women are going through a lot of hormonal change.
So we’re wondering how much of these results is driven by post-menopausal women.”
The study was published in the journal NeuroImage (Ankudowich et al., 2016).