Does Smell Loss Influence Cognition?

Cognition is essential for regulating day-to-day living. People rely on their cognitions to acquire, process and understand information. Cognition involves both conscious and unconscious thinking. It comprises a series of mental activities, including memory, learning, attention, reasoning, language, judging, and decision making. As the aging population continues to grow, more older adults are at risk of cognitive decline and dementia. Therefore, it is essential to identify potentially easy and cost-effective ways to detect early signs of cognitive decline. There is a growing body of literature showing a potential relationship between smell loss and cognitive impairment. Several short odor identification assessments explored in research settings show good validity and reliability in measuring olfactory functioning in elderly populations. The purpose of the current study is to review the current literature examining the relationship between olfactory dysfunction and the risk of cognitive decline among older adults. The present literature review will help guide a future population-based longitudinal study on a similar research topic currently under planning. Knowledge about how olfactory impairment might impact cognition may help healthcare professionals detect early signs of cognitive decline and develop individualized interventions