The Influence of the Tonic Neck Reflex: Vertical Writing

Abstract

The influence of shoulder girdle position on the elaboration of the tonic neck reflex in man was investigated. The subjects were twelve normal adult women volunteers. They volitionally positioned the head to simulate the classical tonic neck reflex postures of Magnus and de Kleijn (1912). Fukuda's vertical writing test (1961) was administered as the diagnostic instrument. A total of 1810 synchronous biplane photographs and 72 columns of letters or circles were interpreted. Data analysis showed that shoulder girdle positioning blocked or enhanced the influence of the head positioning on the extremity used in vertical writing.