Who discovered stuttering?

There doesn't seem to be only one person that discovered stuttering but knowing what it is and what causes it developed through time. In the 6th Century Aetius of Amida was a physician who believed that stuttering was caused by the tongue. He recommended division of the frenum and surgery remained popular for the next few centuries. Johan Frederick Dieffenbach (1795-1847) a German surgeon came up with surgery to treat speech defects in which he would cut a portion of the tongue to help release nerves that cause muscle spasms.  In France in 1830 an author named H. de Chegoin believed that people who stutter had tongues that were disproportionate. J.M.G Itard believed that stuttering was caused by muscular debility. This was treated by putting a fork like object in the lower cavity of the jaw to help support the tongue.  Around the same time in New York, Yaes was studying stuttering and he believed that it was caused by spasms in the glottis. Treatment suggested that patients keep their tongue elevated to the upper palate while speaking. Charles Canon Kingsley  (1819- 1875) believed that stuttering could be traced back to conscious or unconscious imitation. He believed that stuttering could also be due to have the upper teeth sit over the lower teeth. For this he recommended dumbbell exercise,  and placing cork on the back of the teeth. He also believed that boxing was the best sport for someone who stutters. Moses Mendlessohn (1729- 1786) believed that the main reason for stuttering was psychological due to too many thoughts colliding in the brain. Erasmus Darwin (1731-1802) believed emotions such as bashfulness interrupted the movements of the speech articulators.  Joseph Frank (1911) had many beliefs to the cause of stuttering, one being cerebral lesions and the other sexual excess.  In the late 1800’s stuttering was believed to be a neurosis and treated by psychoanalysis.  In 1898 Sandow believed that stuttering was caused by the dread of speaking or the eagerness to speak. Children might stutter when they have physical discomfort or fear and will be fluent when feeling comfortable and at ease.  In 1908 Steckel described stuttering as fear hysteria, with anxiety neurosis beginning in childhood. 

In the 20th Century stuttering was believed to be a psychogenic disorder. As psychoanalysis was being used for trestement, it was stopped around the 1960’s as it was showing to be ineffective.  Today, it is believed that those who stutter have a neuro physical dysfunction that affects the timing required to produce speech. It has also been found that those who stutter have difficulties coordinating their breath and articulation.  The role of genetics in the last few decades has also been studied. In 2010 Dr. Dennis drayna and his team identified the first three genes for stuttering.