As humans age, particularly after middle age, their brain functions, cognitive abilities and memory can deteriorate to varying degrees. Aging-related disorders marked by cognitive decline, particularly dementia, have become increasingly widespread over the past decades.
Estimates suggest that the number of individuals diagnosed with dementia could increase from 55 million in 2019 to around 139 million by 2050. Understanding the factors contributing to cognitive decline and devising methods to detect the first signs of dementia is thus of the utmost importance, as it could help to reliably pick up its emergence and plan therapeutic interventions accordingly.
In recent years, some studies have found a link between people’s ability to perceive and identify odors (i.e., olfactory function) and their cognitive abilities as older adults. While the relationship between olfactory dysfunction and cognitive decline is now well-documented, whether one causes the other or they are the result of similar aging-related or neurodegenerative mechanisms remains unclear.