Absent abdominal reflex 2018-05-02T01:07:23Z A normal abdominal reflex can be observed as a brisk contraction of the umbilicus toward the quadrant that is stimulated. An absent abdominal reflex can point to neurological disease but may also be absent due to other causes such as obesity. Lack of contraction of abdominal muscles in the quadrant of the abdomen that is stimulated by scraping the skin tangential to or toward the umbilicus. Abdominal reflex absent Abnormal superficial reflex