Deterioration of cognitive abilities among the elderly, to the point that social and occupational functions are impaired, is called

dementia

Explanation:

Dementia: The term "dementia" is distinguished as loss of memory, thinking and problem-solving capabilities, and language that is considered severe enough to interfere with an individual's day-to-day life. Alzheimer's is denoted as the most common reason behind dementia. In other words, dementia is a group of social symptoms and thinking that tends to interfere with an individual's daily functioning.

Symptoms: Forgetfulness, disorientation, irritability, loneliness, depression, etc.

Treatment: Therapies, and medication.

In the question above, the given statement represents "dementia".

i honestly speaking this is too long