Abstract

THE CALORIC TEST a. m. HALLPIKE et al. IN A NORMAL MATERIAL With Special Reference to Directional Preponderance in Normal Subjects By KNUD ANKER THOMSEN Introduction. In 1942 Fitzgerald & Hallpike (3) described a new modification of the caloric test for estimation of the vestibular function. This technique, as a matter of fact, offers nothing fundamentally ney. But, as nevertheless it appears to imply certain advantages, we have been using it in more recent years. The method aims at stimulation of the labyrinth - more strictly, the lateral semicircular canal - within physiological limits. The test is carried out by means of water, partly with a temperature of 30°, partly 44' - i. e., a difference of 7' between the temperature of the irrigating water and that of the body as employed by Thornval already in 1917 and in subsequent works (13, 14). As far as that goes, the employment of this difference in temperature by Thornval was more con- sequent, as in each individual case he decided on the temperature of the irrigation after the body temperature had been taken. This difference in temperature gives almost maximal stimulation (Jongkees, 6). Furthermore, a temperature of over 44' is most