A recent study published in the journal Current Biology suggests that difficulty with navigation while walking could be an early sign of Alzheimer's disease. The researchers used a virtual reality model to compare the walking patterns of healthy older adults with those of individuals with mild cognitive impairment (MCI). They found that those with MCI had a lack of understanding of spatial recognition and difficulty accurately gauging their location.
Path integration, which refers to the cognitive ability to understand where one is in a space and how to move within that space, is affected early on by Alzheimer's disease. The entorhinal cortex, a part of the brain that contains special cells called "grid cells," is particularly impacted. These grid cells help individuals understand their position in space by integrating information like location, distance, and direction.
The parietal lobes, which are involved in spatial orientation, are also affected in Alzheimer's disease. This can impact an individual's ability to visually understand the spatial relationships of objects and further impact navigation.
However, it is important to note that difficulty with navigation is just one of the early signs of Alzheimer's. Other symptoms include short-term memory loss, word-finding difficulties, difficulty planning complex tasks or solving problems, and changes in mood or personality. It can sometimes be challenging to distinguish between typical age-related cognitive changes and Alzheimer's disease in the earliest stages.
To diagnose Alzheimer's disease, healthcare experts have developed more accurate ways, such as biomarker tests that measure the presence of amyloid-beta and tau in cerebrospinal fluid. These tests can confirm the diagnosis even in the early stages of the disease. Imaging-based approaches, such as PET scans, can also assess the amyloid-beta or tau burden in the brain. However, these tests are not widely covered by insurance and are mostly used in research studies.
While there is currently no cure for Alzheimer's disease, new medications like lecanemab have been approved to help delay symptoms. However, these medications come with potential side effects, and the decision to start them should be made carefully.
If individuals have concerns about cognitive symptoms, it is essential to discuss them with their doctors to determine if further evaluation is needed. Tests that evaluate thinking and memory, along with a thorough medical history and examination, can help detect subtle changes that may indicate Alzheimer's disease or other neurological disorders. A neurologist can guide patients towards advanced testing for an early diagnosis and appropriate treatment.