BOTTOM REFLEX (Latin reflexus turned back, reflected; synonym plantar reflex) — involuntary bending of fingers of foot, sometimes in a combination to bending of a shin and a hip, arising at shaped irritation of a bottom surface of foot. The reflex normal has bystry speed, than significantly differs from patol, protective reflexes, for to-rykh slowness of reflex movement is characteristic. The volume of this movement is individual and very various: in one cases there is only a bending of fingers of foot, in others — a vigorous otdergivaniye of all leg. The reflex arc of P. of river corresponds to L5 — S1-2 to segments of a spinal cord. At defeat of this reflex arc in the field of the corresponding segment of a spinal cord, roots of a spinal or peripheral nerve of P. of river dies away. In case of defeat of cortical and spinal pyramidal ways of P. of river undergoes change: in response to shaped irritation of a sole there is a back extension of a thumb and fan-shaped discrepancy of other fingers (see. Babinsky reflex ).
See also Reflex .