The Serotonin Hypothesis of Schizophrenia: A Historical Case Study on the Heuristic Value of Theory in Clinical Neuroscience

Clinical examination of the reliability and coherence of the evidence concerning modern neurochemical theories of mental disorders has led some scholars to conclude that support for many of these theories is weak. Nevertheless, these theories continue to be widely promoted. One explanation that has been offered for continued adherence to questionable theory is that it stimulates and gives direction to research. The heuristic value of theory is examined in the present paper by tracing the discoveries that followed from an old theory of schizophrenia, which is--by current consensus--false. It is shown that the original serotonin hypothesis of schizophrenia did, in fact, lead to significant advances in neuropharmacology, neurology and psychiatry.