Gegenhalten is

Paratonic rigidity or Gegenhalten: an erratic, fluctuating, "pseudoactive" increase in resistance to passive movement.On repeated flexing and extending the patient's arm at the elbow, on abruptly ceasing the arm is extended and continues the sequence by flexion(facilitory paratonia) Clasp-knife rigidity: increased tension in the extensor of a joint when it is passively flexed, giving way suddenly on exeion of fuher pressure; seen in upper motor neuron disease. cogwheel rigidity: tension in a muscle that gives way in little jerks when the muscle is passively stretched Leadpipe Rigidity: posture adopted when the rigidity of the limb is maintained equally throughout the passive flexion. Hysterical rigidity: seen in hysterical patients the resistance to passive movement increases in propoion to the effo applied by the examiner rigidity reflex: the state of immobility generated in female animals, especially those in estrus, when they make physical contact with a male. Reference: P.404 chap 2.1 The Neuropsychiatric Approach to the Patient(Kaplan & Sadock's Comprehensive Textbook of Psychiatry, 9th Edition)