When people think about cognitive decline, they often imagine the obvious symptoms: forgetfulness, confusion, or difficulty finding the right words. While these signs are common in conditions like dementia, there are other, less-known symptoms that often go unnoticed.
These rare signs can appear years before the more recognizable symptoms and may provide early warnings of changes in brain health. Identifying them early could help people seek medical advice sooner and potentially slow the progression of cognitive decline.
One surprising symptom linked to early cognitive decline is a loss of the sense of smell. Researchers have found that the ability to detect and identify smells often declines in the early stages of Alzheimer’s disease and other forms of dementia.
A 2017 study published in The Lancet Neurology followed older adults for several years and discovered that those with a declining sense of smell were more likely to develop cognitive impairment. This symptom is thought to be connected to changes in the brain’s olfactory bulb and areas involved in memory processing.
Another subtle sign is changes in mood or personality. While occasional mood swings happen to everyone, persistent changes, such as becoming more withdrawn, irritable, or anxious, could indicate underlying cognitive problems.
A study in JAMA Psychiatry in 2019 found that individuals who experienced unexplained apathy or loss of interest in activities they once enjoyed were at higher risk for dementia. These changes are thought to occur because the brain regions responsible for emotional regulation may be affected in the early stages of cognitive decline.
Sleep disturbances are another less obvious clue. People with cognitive decline often experience changes in their sleep patterns, such as trouble falling asleep, waking frequently during the night, or feeling excessively sleepy during the day.
Research published in Neurology in 2020 linked poor sleep quality and disruptions in deep sleep to an increased buildup of amyloid plaques in the brain, a hallmark of Alzheimer’s disease. Sleep problems may not always seem connected to brain health, but they could be an early sign of trouble.
Changes in vision or spatial awareness can also signal cognitive decline. This doesn’t just mean blurry vision but includes difficulty judging distances, struggling to follow moving objects, or having trouble navigating familiar places.
A study in The Journal of Alzheimer’s Disease in 2018 highlighted that people who frequently got lost or had trouble recognizing landmarks were more likely to show early signs of cognitive impairment. These issues are believed to result from changes in the brain areas responsible for processing visual and spatial information.
Language problems that are subtle and inconsistent might also go unnoticed. For example, someone might occasionally mix up words, pause more often while speaking, or struggle to follow a fast-paced conversation.
While these issues can be mistaken for normal aging, research shows they could be linked to mild cognitive decline. A 2021 study in Brain and Language found that people who began to show slight difficulties with word recall were more likely to develop more noticeable cognitive problems later.
Even changes in decision-making and problem-solving can hint at cognitive decline. Someone might find it harder to plan tasks, manage finances, or follow multi-step instructions. These issues often go unnoticed because they can be attributed to stress or busyness rather than brain health.
However, studies have shown that early impairments in executive function, the brain’s control center for managing tasks, are a key predictor of dementia.
These rare and often overlooked symptoms—loss of smell, mood changes, sleep disturbances, vision problems, subtle language issues, and difficulty with decision-making—may not seem connected to cognitive decline at first glance.
However, research suggests that they could be early warning signs of changes in brain health. Recognizing them early could provide an opportunity to seek medical advice, make lifestyle changes, and explore treatments that may help slow the progression of cognitive impairment.
Cognitive decline is complex, and its early symptoms can be subtle. Staying informed about these lesser-known signs can help individuals and their loved ones take proactive steps toward maintaining brain health and seeking help when needed.
If you care about brain health, please read studies about Vitamin B9 deficiency linked to higher dementia risk, and cranberries could help boost memory.
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