Abu Ali ibn Sina or Avicenna
Avicenna, a Muslim and native of Persia, was a physician, scientist, philosopher, statesman and poet, famous and well respected both in his own time and in later generations. He wrote over 100 books on science, religion and philosophy, with the most famous being his textbook, Canon of Medicine. The Canon contained a comprehensive review of medicine and medical practice of the time. Central to Avicenna's medicine was the theory of humors as developed most fully by Galen. Avicenna's book was used for several decades after his death, both in the Islamic world and in Europe.
Avicenna subscribed to a ventricular theory (sometimes called cell theory), wherein the four ventricles of the brain were seen as faculties involved in the sensory and cognitive processing. Avicenna's theory in his own words:
The sensus communis is located in the forepart of the front ventricle of the brain. It receives all the forms which are imprinted on the five senses and transmitted to it from them. Next is the faculty of representation located in the rear part of the front ventricle of the brain, which preserves what the sensus communis has received from the individual five senses even in the absence of the sensed object. Next is the faculty of 'sensitive imagination' in relation to the animal soul. This faculty is located in the middle ventricle of the brain. Then there is the estimative faculty located in the far end of the middle ventricle of the brain. Net there is the retentive and recollective faculty located in the rear ventricle of the brain (Rahman, 1952, p. 31).
Avicenna's Canon includes data on laryngeal anatomy and physiology, includes a chapter on the production of voice and voice disturbances. His picture of tongue musculature, drawn from an earlier work of Galen, became a classic and influenced views of the tongue for many years.
In keeping with his theory of humors Avicenna portrayed stuttering as being caused by a softening of the tongue and excess moisture on the tongue (Wollock, 1997, p. 208 fn. 43) and voice problems as also being caused by too much moisture moisture (hoarseness), by cold temperature(weak), by dryness (irritated) and by heat (loud) (O'Neill, 1980, p. 110). In his words:
People who lisp are liable to gastro-intestinal catarrh, and such people do not stand strong purges in consequence. All the same, many do run the risk of gastro-enteritis because of the materials which flow down from the head (Cameron, 1930, p. 483).
Avicenna recommended physical exercise as a therapy for both speech and voice disorders. For example borrowing from the work of Aristotle, he recommended vociferation, or shouting into the air on a regular basis, as a way for exercising the organ and muscles of phonation (Finney, 1966, p. 405, O'Neill, 1980, p. 107).
Avicenna saw patients throughout the Islamic empire, traveling to where they were. He became physician to several sultans and the vizier of the Shii Buyid dynasty, which ruled what now is western Iran and southern Iraq.
In his Book of Healing, Avicennadiscussed the mind, its existence, the mind and body relationship, sensation, and perception. He said that the influence of the mind on the body can be found in voluntary movements. He also saw a second level of influence of the mind on the body as being from emotions and the will. He also felt that strong negative emotions can negatively affect the body's vegetative functions.
Avicenna was also the first to divide human perception into external and internal senses. The five internal senses that he discovered were: the sensus communis (seat of all senses) which integrates sense data into percepts; the imaginative faculty which conserves the perceptual images; the sense of imagination which acts upon these images by combining and separating them, serving as the seat of the practical intellect; instinct) which perceives qualities (such as good and bad, love and hate, etc.) and forms the basis of a person's character whether or not influenced by reason; and intentions which conserve all these notions in memory.
Writings of Avicenna
Avicenna (1930) A treatise on the Canon of Medicine of Avicenna, Incorporating a translation of the first book. Translated by O. Cameron Gruner. London: Luzac & Co.
Avicenna (1963) Arabic Phonetics: Ibn Sina's Risalah on the points of articulation of the speech sounds. Translated by Khalil I. Semaan. Lahore: Ashraf .
Avicenna (1966). The General Principles of Avicenna's Canon of Medicine, edited and translated by Mazhar H. Shah. Karachi: Naveed Clinic.
Avicenna (1974) The Life of Ibn Sina, edited and translated by William E. Gohlman. Albany: State University of New York Press.
Writings about Avicenna
Finney, G. (1966). Medical theories of vocal exercise and health. Bulletin of the History of Medicine, 5, 395-406.
Hasse, Dag Nikolaus (2000). Avicenna's de Anima in the Latin West: the formation of a peripatetic philosophy of the soul, 1160-1300. London
O'Neill, Y. (1980). Speech and speech disorders in western thought before 1600. Westport Connecticut: Greenwood Press.
Rahman, F. (1952). Avicenna's psychology. London: Oxford University Press.
Siraisi, N. (1987). Avicenna in Renaissance Italy. Princeton, NJ: Princeton University Press.
Wickers, G. M. (Ed.) (1952). Avicenna: Scientist and philosopher. London.
Wollock, J. (1997). The noblest animate motion: Speech, physiology and medicine in pre-Cartesian linguistic thought. Philadelphia, John Benjamins Publishing Company.