Sensory pathways of the somatosensory system. Reflexes. Cross extensor reflex and central pattern generators. Parts of the Central Nervous system: cerebral cortex, diencephalon, brainstem, cerebellum, spinal cord. Peripheral nerves. Skin. Cutaneous nerve receptors. Testing the 5 sensory modalities (pain, temperature, pressure, touch, vibration). Cutaneous receptors. Deep receptors. Sensory Homunculus. Dorsal columns quantitative sensations (touch, pressure and proprioception (position)). Spino-thalamic tract qualitative sensations (pain and temperature). Gate control of pain. Reflex descending control of pain. Role of enkephalins and endorphins. Neuropathic pain. Romberg Test. Olfactory pathways.