the therapeutic effects. Latest biological hypotheses of mental health disorders New research indicates different biological mechanisms may underlie some mental health disorders, only indirectly related to neurotransmitters and the monoamine chemical imbalance hypothesis. Recent research indicates a biological "final common pathway" may exist which both electroconvulsive therapy and most current antidepressant drugs have in common. These investigations show recurrent depression may be a neurodegenerative disorder, disrupting the structure and function of brain cells, destroying nerve cell connections, even killing certain brain cells, and precipitating a decline in overall cognitive function. In this new biological psychiatry viewpoint, neuronal plasticity is a key element. Increasing evidence points to various mental health disorders as a neurophysiological problem which inhibits neuronal plasticity. This is called the neurogenic hypothesis of depression. It promises to explain pharmacological antidepressant action, including the time lag from taking the drug to therapeutic onset, why downregulation (not just upregulation) of neurotransmitters can help depression, why stress often precipitates mood disorders, and why selective modulation of different neurotransmitters can help depression. It may also explain the neurobiological mechanism of other non-drug effects on mood, including exercise, diet and metabolism. By identifying the neurobiological "final common pathway" into which most antidepressants funnel, it may allow rational design of new medications which target only that pathway. This could yield drugs which have fewer side effects, are more effective and have quicker therapeutic onset. There is significant evidence that oxidative stress plays a role in schizophrenia. Criticism of A number of patients, activists, and psychiatrists dispute biological psychiatry as a scientific concept or as having a proper empirical basis, for example arguing that there are no known biomarkers for recognized psychiatric conditions. This position has been represented in academic journals such as The Journal of Mind and Behavior and Ethical Human Psychology and Psychiatry, which publishes material specifically countering "the idea that emotional distress is due to an underlying organic disease." Alternative theories and models instead view mental disorders as non-biomedical and might explain it in terms of, for example, emotional reactions to negative life circumstances or to acute trauma. Fields such as social psychiatry, clinical psychology, and sociology may offer non-biomedical accounts of mental distress and disorder for certain ailments and are sometimes critical of biopsychiatry. Social critics believe biopsychiatry fails to satisfy the scientific method because they believe there is no testable biological evidence of mental disorders. Thus, these critics view biological