2. Conditions of spasm understood by analogy to fright. Plain Questions (素问 sù wèn) states that liver disease is associated with fright. The liver is the viscus of wind and wood; it governs the sinews. The liver is associated with wood in the five phases, and just as trees (wood) are swayed by the wind, so the liver can be stirred by internal wind. Arched-back rigidity and convulsions are seen as shaking and bending the body by wind. Fright, like wind, causes spasm, since the sinews (muscles) of a person subjected to a frightening stimulus will tense. For this reason, fright is associated with liver-wood. Wind and fright both manifest as hypertonicity of sinews, which are governed by the liver. See fright wind.