Final answer:
Deviation from ideal mental health refers to significant departures from what is considered healthy psychological functioning, such as those seen in mental illnesses like schizophrenia, major depression, and anxiety disorders, as delineated in the DSM.
Step-by-step explanation:
Deviation from ideal mental health is one definition of psychopathology which implies that mental illness arises when there's a significant departure from a set of criteria regarded as normal or healthy psychological functioning. The idea is that just as physical health can be understood in terms of certain standards, so can mental health.
These standards might include the ability to maintain fulfilling relationships, feeling comfortable about oneself, the capacity to cope with stress, and the realization of one's potential. In this sense, mental illnesses, such as schizophrenia, major depression, and anxiety disorders, reflect deviations from the psychological patterns that are considered normal or ideal.
The DSM, published by the American Psychiatric Association, is a critical resource that outlines the symptoms needed to diagnose a variety of mental disorders.
Classification and understanding of these disorders have evolved; for instance, homosexuality was once wrongly classified as a mental illness and was later removed from the DSM due to research and activism that demonstrated it to be a normal variant of human behavior. Ultimately, psychopathology can be seen as patterns of thoughts, feelings, or behaviors that are vastly at odds with cultural norms and that lead to personal distress or impaired functioning.