Organization of sensory pathways
A sensory neuron that delivers sensations to the CNS is often called a first-order neuron. The cell body of-order general sensory neuron is located in a dorsal root ganglion or cranial nerve ganglion. In the CNS, the axon of that sensory neuron,which may be located in the spinal cord or brain stem. ... As a result, the right of the thalamus receives sensory information from the left side of the body, and vice versa. The axons of the third-order neurons ascend without crossing over and synapse on neurons of the primary sensory cortex of the cerebral hemisphere.