The symptoms of dementia mainly include the following aspects:

First, there is evident impairment in cognitive functions, primarily involving memory decline. Initially, it may predominantly affect recent memory, with patients often forgetting recent events. As the disease progresses, they may start forgetting events from the distant past as well. Additionally, patients may experience a decline in calculation skills, judgment, execution, and comprehension abilities; their capacity to learn and work is comprehensively impaired. Spatial dysfunction can also occur, causing disorientation and frequent episodes of getting lost.

Secondly, in the later stages, patients may display changes in behavior and personality, alongside corresponding psychological symptoms. For example, the patient might become aggressive, restless, and exhibit hallucinations visually and auditorily. Wandering at night is another common symptom.

Thirdly, in the later stages, patients might show clinical signs such as muscle atrophy and paralysis. Incontinence is also a common symptom.