Dorsal columns-medial lemniscus:

The colored lines indicate the path of nerves in the dorsal columns-medial lemniscus pathway.

AKA posterior columns-medial lemniscus. This is a pathway that carries fine tactile and proprioceptive information from the body up to the thalamus. The dorsal columns first carry such information to the medulla. There the information is passed on to the medial lemniscus, which proceeds to the thalamus.

Learn more:

2-Minute Neuroscience: Touch and the Dorsal Columns-Medial Lemniscus