When he first contemplates the murder of Duncan, he says its "horrid image doth unfix my hair"
If good, why 
do I yield to that suggestion / Whose horrid image doth unfix my hair / And make 
my ... To contemplate such horror and steel Macbeth to kill Duncan she calls 
upon... [DOC] [TLE] Macbeth Navigator: Macbeth: His Fear of Fear [PAR] ... horrid image doth unfix my hair / And make my seated heart knock at my ribs, / 
Against the use of nature?