Ha! Is that medical term? I am positive I suffer from that Many things from which I used to experience pleasure pre-injury I certainly cannot. Looks like it is also a form of depression. I tell people some of my brain circuits are permanently broken because of brain contusion and they have no idea of course.

Then I read this in Wikipedia and I always feel very depressed in mornings and feel ok in the evenings and night. This is interesting.

Significance in depression
As a clinical symptom in depression, anhedonia rates highly in making a diagnosis of this disorder. Some people describe the feeling as being "strung out". The Diagnostic and Statistical Manual of Mental Disorders (DSM) describes a "lack of interest or pleasure", but these can be difficult to discern given that people tend to become less interested in things which do not give them pleasure. The DSM criterion of weight loss is probably related, and many individuals with this symptom describe a lack of enjoyment of food. People suffering from anhedonia in association with depression generally feel suicidal in the morning and better in the evenings as sleep seems the only escape resembling death and can portray any of the non-psychotic symptoms and signs of depression.