Physical disorder
A physical disorder is often used as a term in contrast to a mental disorder, in an attempt to differentiate medical disorders that have an available mechanical test, from those disorders which have no laboratory or imaging test, and are diagnosed only by behavioral syndrome.
Differentiating the physical disorders from mental disorders can be a difficult problem in both medicine and law, most notably because it delves into deep issues, and very old and unresolved arguments in philosophy and religion. Many materialists believe that all mental disorders are physical disorders of some kind, even if tests for them have not yet been developed.
Some recognized physical disorders produce significant behavioral changes. For example, fever, head trauma, and hyperthyroidism can produce delirium.
