I'm in difficulties because of the demented old woman next door wreaking havoc in my fields.

In relating the circumstances which have led to my confinement within this refuge for the demented, I am aware that my present position will create a natural doubt of the authenticity of my narrative.

Your impertinent attempts at national self-humilitiation have the vagary of a demented maniac, provide you with no condescension but accumulate contempt in the eyes of others and your total worthlessness is congruentially equivallent to your repugnantly low grammatic skills.

I think Tom is demented.

Being unable to detect sarcasm is a warning sign for frontotemporal dementia.

I'm not demented.

Multilingualism may prevent dementia.

Fool Muttonhead is truly sick and demented.

Eating a balanced diet, exercising regularly, not smoking, and getting your blood pressure and cholesterol checked regularly are key ways to reduce your risk of dementia.

Dementia ran in Yanni's family.