TOPICAL ARRANGEMENT WITHIN THE SPINOTHALAMIC TRACT OF THE MONKEY

Abstract

It was Spiller1who first observed that painful and thermal sensations are carried within the anterolateral columns of the spinal cord and that surgical section of the anterolateral part of the cord will result in contralateral analgesia and thermanesthesia below the lesion. From surgical experiences gained as a result of the application of this remarkable observation Foerster and Gagel,2Hyndman and Van Epps3and Walker4have amplified Spiller's observations and have suggested that the fibers from different levels of the spinal cord are segmentally organized within the anterolateral columns and within the brain stem. The present study was undertaken to determine the topical arrangement of the fibers within the spinothalamic tract in the monkey. METHOD OF STUDY Using anesthesia induced by pentobarbital sodium and aseptic technic, unilateral anterolateral chordotomies were made in 6 Macacus rhesus monkeys at different levels of the spinal cord, from the upper