What do you mean by the term arch reflex

Question

What do you mean by the term arch reflex?

Answer 1

In some conditions the movement of the skeletal striated muscles doesn’t depend on commands of the superior motor neurons, that is, it is not triggered by the volition.

Involuntary movements of such muscles might happen whenever sensory fibers which make indirect or direct connection with inferior motor neurons are unpredictably stimulated in situations which suggest danger to the body. This occurs, for illustration, in the patellar reflex, or knee jerk reflex, whenever a sudden percussion on the knee patella (or kneecap) triggers an involuntary contraction of the quadriceps (that is, the extension muscle of the thigh). The other instance of the arch reflex takes place when someone steps on a sharp object: one leg retracts and the other, by the arch reflex, distends to sustain the equilibrium of body.