Final answer:
Second-order neurons from the medial lemniscus and spinothalamic tracts indeed synapse with third-order neurons in the thalamus, which then project to the cerebral cortex, making the statement True.
Step-by-step explanation:
The question pertains to the sensory pathways within the nervous system, specifically the dorsal column-medial lemniscus pathway and the spinothalamic tract. These are two of the major somatosensory pathways that carry information to the brain. In the dorsal column-medial lemniscus pathway, axons of the second-order neurons carry sensory information originating from sensory receptors through the dorsal columns to the medulla, where they synapse with second-order neurons. These neurons then decussate and ascend as the medial lemniscus to terminate in the thalamus. Similarly, in the spinothalamic tract, axons from second-order neurons cross over in the spinal cord and ascend to the brain, entering the thalamus. In the thalamus, both pathways synapse with third-order neurons. The axons from the third-order neurons then project to the postcentral gyrus of the cerebral cortex. Therefore, the statement that second-order neurons from the medial lemniscus and spinothalamic tracts synapse with third-order neurons in the thalamus is True.