Research has suggested that a reward deficiency syndrome may contribute to

A) insomnia.
B) alcohol dependence.
C) schizophrenia.
D) Parkinson's disease.

Reward Deficiency Syndrome

A proposed neurobiological condition characterized by the inability to feel pleasure, leading to various addictions and compulsive behaviors.

Alcohol Dependence

A medical condition characterized by a strong craving for alcohol, loss of control over its use, and continued drinking despite adverse consequences.