from http://www.MedicineNet.com -

Definition of Anhedonia

Anhedonia: Loss of the capacity to experience pleasure. The inability to gain pleasure from normally pleasurable experiences. Anhedonia is a core clinical feature of depression, schizophrenia, and some other mental illnesses.

An anhedonic mother finds no joy from playing with her baby. An anhedonic football fan is not excited when his team wins. An anhedonic teenager feels no pleasure from passing the driving test.

"Anhedonia" is derived from the Greek "a-" (without) "hedone" (pleasure, delight). Other words derived from "hedone" include hedonism (a philosophy that emphasizes pleasure as the main aim of life), hedonist (a pleasure-seeker), and hedonophobia (an excessive and persistent fear of pleasure).

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it means you don't feel the feelings of happiness, enjoyment, or being happy about anything, basically your feelings stay neutral everything is just ok but not great, not happy, not have fun doing anything that most people would find enjoyable, or like to do.

A friend explained it to me as in she has no likes.. she either hates everything or eats it, does it and so on just because its there and expected not out of because she likes to or wants to. its just something to pass the time of day.

Ask her if she likes chocolate and she will say its ok. hand her a piece of chocolate and she will eat it just because some one handed it to her, not out of whether or not she likes the taste or that brand or to experience something new. its there so she eats it kind of thing.