Final answer:
The medial lemniscus is a fiber tract responsible for transmitting sensory information from the periphery to the brain. It ascends the brain stem and terminates in the thalamus.
Step-by-step explanation:
The medial lemniscus is a fiber tract of the dorsal column system that extends from the nuclei gracilis and cuneatus to the thalamus. It is involved in transmitting sensory information, particularly touch and proprioception, from the periphery to the brain.
The axons of the medial lemniscus ascend the brain stem and terminate in the thalamus, where they synapse with the third neuron in their pathway. The third neuron then projects its axons to the postcentral gyrus of the cerebral cortex for further processing and perception of somatosensory stimuli.