[Blog](https://vittalkamath.com/blog) # Dementia 19 May 2026 Dementia is a decline in mental ability severe enough to interfere with daily life. It affects memory, language, judgement and behaviour. ## Common signs and symptoms - **Memory loss:** forgetting recent conversations, appointments, names. - **Difficulty communicating:** struggling to find words or to follow conversations. - **Disorientation:** getting lost in familiar places, losing track of dates and time. - **Cognitive decline:** trouble planning, organising, managing money or complex tasks. - **Changes in behaviour:** mood swings, apathy, personality shifts, poor judgement. ## Main types - **Alzheimer’s disease:** the most common. Caused by abnormal build-ups of protein: amyloid plaques and tau tangles. - **Vascular dementia:** from reduced blood flow to the brain, due to strokes or small-vessel disease. - **Lewy body dementia:** abnormal deposits of the protein alpha-synuclein. It affects thinking, movement and sleep, and causes visual hallucinations. Related to Parkinson’s. - **Frontotemporal dementia:** targets the frontal and temporal lobes. Early changes in personality, behaviour or language. ## Diagnosis: rule out reversible causes Not all memory loss is dementia. These can mimic it: **thyroid problems**, **vitamin B12 deficiency**, side effects of medicines, depression, infections. Common evaluations: - **Neurological exam:** checks reflexes, balance and the senses. - **CT scan or MRI:** looks for a stroke, bleeding, tumours or fluid build-up. - **PET scan:** shows brain activity and amyloid protein deposits. - **Lab tests:** B12 levels, thyroid function, spinal fluid for infection or inflammation. - **Psychiatric exam:** depression often overlaps with, or mimics, the symptoms of dementia. ## Treatment and management - **Medicines:** - cholinesterase inhibitors like donepezil may improve symptoms for a time; - other medicines for depression, sleep problems, hallucinations, agitation, or Parkinson’s-like movements. - **Occupational therapy:** makes the home safer and teaches coping strategies to prevent accidents. - **Changes to the surroundings:** reduce clutter and noise to help focus. Secure dangerous items like knives, car keys and medicines. - **A care facility:** may be needed when behaviour can’t be managed safely at home. ## Reducing the risk - Avoid head injury, and treat hearing loss. - Stop smoking. - Eat a Mediterranean-style diet. - Exercise regularly. - Control diabetes, high blood pressure and high cholesterol. The saying “what’s good for the heart is good for the brain” holds up. Vascular health and brain health are closely linked. [All articles](https://vittalkamath.com/blog)