Flexor reflex

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In animal neurology, a flexor reflex is a reflex that can be triggered on both the hind and front limbs. The animal is usually placed on its side. When pinching the toe, the skin between the toes or the ball of the foot , the entire limb of the respective side flexes reflexively.

The reflex is mediated on the hind limb via the sciatic nerve, the reflex center is in the spinal cord segments L4-S3. Are on the forelimb of the musculocutaneous nerve , axillary nerve , median nerve , radial nerve and ulnar nerve involved, the reflective center is C6 to Th1.

An absence (an areflexia ) or a decreased / delayed response ( hyporeflexia ) indicates damage to the lower motor neuron. An abnormal reflex response occurs with the crossed extensor-flexor reflex . In addition to the flexion of the irritated limb, the limb on the opposite side is stretched. This abnormal reflex is observed through damage to the spinal cord above the respective reflex center.

The flexor reflex in humans

The flexor reflex also occurs in humans. It is a foreign reflex with a spinal, polysynaptic reflex arc . The flexor reflex of one leg is always associated with a crossed extensor reflex. The leg that is contralateral to the origin of the pain is stretched. The interaction of the flexor reflex and the crossed extensor reflex serves to maintain balance.

literature

  • André Jaggy: Atlas and textbook of small animal neurology. Schlütersche, Hannover 2005 ISBN 3-87706-739-5 .
  • Niels Bierbaumer , Robert F. Schmidt: Biological Psychology . 6th completely revised and expanded edition. Springer, Heidelberg 2006, ISBN 3-540-25460-9 , pp. 275f. ( Springer textbook ).