Can untreated mental illness mimic dementia symptoms? Yes, conditions like depression can produce brain fog, memory lapses, and confusion that closely resemble dementia, often leading to misdiagnosis.
People facing memory problems might worry about dementia right away. They forget why they entered a room, lose track of conversations, or struggle with daily tasks. These issues can feel like the mind is slipping away. In reality, untreated depression often causes these same problems. Doctors call this pseudodementia, where mental health issues trick people into thinking they have a brain disease.[1]
Depression changes how the brain works. It affects areas like the hippocampus, which handles memory. During a depressive episode, brain function slows down, creating confusion and withdrawal. Unlike true dementia, which worsens slowly over years, depression-related problems can start suddenly. People with depression usually notice and complain about their memory gaps, while those with dementia might hide them.[1]
Studies back this up. Tests like the Montreal Cognitive Assessment show lower scores in depressed older adults due to apathy and slowed thinking. These scores improve when depression is treated, and most patients do not go on to develop dementia.[3]
Other mental health issues can play a role too. Severe anxiety or untreated conditions might lead to clouding of consciousness, a foggy mental state with poor focus and problem-solving. This brain fog overlaps with dementia signs like disorientation.[4]
Not every mimic comes from mental illness alone, but untreated cases make it worse. For example, depression in later life raises dementia risk, but it is not always a direct cause. Getting the right diagnosis matters because treatments differ. Mental health care can reverse these symptoms through therapy or medication, thanks to the brain’s ability to heal.[1]
Spotting the difference takes medical help. Doctors look at how fast symptoms appear, patient awareness, and response to treatment. Early checks prevent wrong labels and needless fear.
Sources
https://safesoundtreatment.com/does-depression-cause-memory-loss/
https://int.livhospital.com/i-thought-my-brain-fog-was-dementia/
https://pmc.ncbi.nlm.nih.gov/articles/PMC12734739/
https://en.wikipedia.org/wiki/Clouding_of_consciousness
https://my.clevelandclinic.org/health/diseases/9170-dementia
