Final answer:
Delirium is characterized by rapid-onset confusion, while dementia involves a gradual deterioration over time. Delirium is temporary, while dementia is a chronic condition. Apathetic thought process is more commonly associated with dementia than delirium.
Step-by-step explanation:
Delirium and dementia are both cognitive disorders, but they have some distinct differences. One characteristic mental change that occurs with delirium and differentiates it from dementia is rapid-onset confusion. Delirium is typically characterized by a sudden and severe decline in cognitive function, whereas dementia involves a more gradual deterioration over time. Additionally, delirium is usually temporary and lasts for a shorter duration, while dementia is a chronic condition that lasts over several years. Another differentiating factor is apathetic thought process, which is not commonly associated with delirium but can be observed in some cases of dementia.