Research shows age plays limited role in cognitive decline

Happy young boy playing chess with granddad

Cognitive decline is among the most feared aspects of growing older, yet new research suggests that ‘senior moments’ play less of a part in the normal ageing process than once thought.

Through increasing screening measures and using modern brain imaging technologies, a research team from The Florey Institute of Neuroscience and Mental Health have discovered that previous studies overestimated the effect of normal aging processes on the cognitive abilities of healthy older adults.

Lead researcher Karra Harrington said that when measuring age-related decline in cognitive function there appears to be little to no deterioration, and it commences at an older age than previously estimated - in the seventies rather than the sixties.

The results show that cognitive decline in older adults is evident only on complex neuropsychological tests, while performance on simpler neuropsychological tests is relatively stable throughout late life.

Ms Harrington said that previous studies had a more lax approach to screening measures and were likely to have included individuals with cognitive impairments not caused from the normal ageing process such as early dementia, medical conditions or excessive alcohol consumption.  

“Normal ageing appears to be associated with some subtle changes in the speed of problem solving and when learning new information, however the accuracy of decisions does not deteriorate,” she said.

“It is normal at any age to have occasional memory lapses, especially when we are tired or not concentrating and these should not be cause for concern.

“However, it is not normal to become more forgetful as a result of ageing. Consistent forgetfulness where the information doesn’t come back later could be a sign that something abnormal is impacting on memory or other abilities and should be investigated by a medical professional.”

“My research reiterates the need to enhance the early detection and diagnosis of cognitive changes that are associated with disease and dementia.”

Unsupported stereotypes

In a survey conducted by the Australian Human Rights Commission in 2013, younger Australians reported that they perceived age to be associated with a loss of mental capacity and forgetfulness.

These attitudes are supported and reinforced by previous research on the cognitive ability of older adults which is likely to have overestimated the effect of age on cognitive function.

The same survey also suggests that these stereotypes also influence the way that older adults are treated, with 43% of Australians aged over 65 reporting experiences of age discrimination, being ignored, treated with disrespect, or subjected to jokes about ageing.

“A lot of the older adults that I have worked with as a psychologist express concerns about how their memory or cognition might be changing as they’re growing older. This is the case even for people who are actually ageing really well in terms of both their physical and cognitive health and who don’t have dementia,” said Ms Harrington.

“Older adults have a lot to offer by way of knowledge and experience. Even when someone has some cognitive impairment, they are often still able to access and apply past experience, skills, and knowledge to a situation. I feel that it is important to focus on what a person is able to do and work with them to overcome difficulties or challenges, rather than focusing on what they are no longer able to do.

“What I wanted to do with my research was to develop some clarity around what changes in cognitive ability are normal as we grow older and what changes might be early warning signs for illness.”

“Our results show that if you are healthy in your older age then you can expect very little deterioration in thinking.

“I hope this information is used to enhance early detection and treatment of dementia or other cognitive difficulties, as well as to alleviate some of the concerns about cognitive changes expressed by healthy older adults,” she said.

For information on the symptoms and signs of dementia visit the Alzheimer’s Australia website. Dementia Australia also offers support, information, education and counselling. Contact the National Dementia Helpline, an Australian Government Initiative: 1800 100 500.



Karra Harrington received an Alzheimer’s Australia Dementia Research Foundation (AADRF) PhD Scholarship in 2014. A second author of this project, Yen Ying Lim, also received an AADRF Post-doctoral Fellowship in 2014. This project incorporated data from and provided data for the Australian Imaging Biomarkers and Lifestyle (AIBL) study.