<prompt> Which of the following are NOT features of Coicospinal tract lesion? 1. Spasticity 2. Resting tremor 3. Exaggerated tendon reflexes 4. Extensor plantar response 5. Cogwheel rigidity1,2 32 54 5None  <response>: Resting tremors are present in parkinsons disease and in extrapyramidal disorder, not in coicospinal tract disorder. Rigidity is increased tone that is present throughout the range of motion a lead pipeor plastic stiffness and affects flexors and extensors equally; it sometime has a cogwheel quality that is enhanced by voluntary movement of the contralateral limbsreinforcement. Rigidity occurs with ceain extrapyramidal disorders such as parkinsons disease . Coicospinal tract lesions: Axons of the pyramidal or coicospinal system descends through the brainstem in the cerebral peduncle of the midbrain, the basis points, and the medullary pyramids. At the cervicomedullary junction, most pyramidal axons decussate into the contralateral coicospinal tract of the lateral spinal cord, but 10-30 remain ipsilateral in the anterior spinal cord. Muscle stretch tendon reflexes are usually increased with upper motor neuron lesions, although they may be decreased or absent for a variable period immediately after onset of an acute lesion. This is usually -but not invariably -accompanied by abnormalities of cutaneous reflexes such as superficial abdominals and in paicular, by an extensor plantar Babinski response. Ref: Harrison 17e, page 147 ; Ganong 23e, page 253 