"refers to a psychological state in which an individual feels overexcited and unrealistically optimistic."

The correct answer would be Mania. Mania refers to a psychological state in which an individual feels over excited and unrealistically optimistic.

Explanation:

When a person has high level of mood swings, have great periods of excitements, delusions or over activity, and he feels optimistic to a level where it seems unrealistic, he is called a maniac, and he has a mental illness called mania. He feels excessive enthusiasm. There are many causes of Maniac Syndrome. Neurologic, toxic and metabolic causes are some of the causes. This is considered a bipolar disease.  

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