To the Editor.
—We read with interest the report by Rockey and Griep entitled "Behavioral Dysfunction in Hyperthyroidism: Improvement With Treatment," in the September 1980 Archives (140:1194-1197). We in the Endocrine Disease Section also have been working on a similar subject-the behavioral aspects of thyroid diseases—at the psychologic laboratory of the Cerrahpaşa Medical Faculty at the Institute of Nuclear Medicine in Istanbul, Turkey.In our studies, we used a large battery of psychologic tests that measured the following: reaction time, motor coordination, simple learning and problem solving, visual illusions, perceptual span, intelligence, organicity (Bender Gestalt test, Memory for Design test, and Minnesota Multiphasic Personality Inventory), and the psychosomatic and neuropsychiatric tendencies of a subject (Cornell index). These studies also included patients with simple goiter and various uninodular goiter disorders as well as the hyperthyroid patients in our experimental groups (N = 119). We compared the performances of the groups with