All of the following descriptions refer to specific ascending pathways except one: (a) they include the fasciculus gracilis and fasciculus cuneatus, which terminate in the thalamus; (b) they include a chain of three neurons; (c) their connections are diffuse and polymodal; (d) they are concerned with precise transmission of one or a few related sensory modalities

POSTERIOR COLUMN-MEDIAL LEMNISCUS SENSORY (ASCENDING) PATHWAY TO THE CEREBRAL CORTEX

Sensory ascending pathways involving the fasciculus gracilis and fasciculus cuneatus do not terminate in the thalamus.

Here is a brief description of this pathway.

It is called the posterior column-medial lemniscus pathway to the cortex. First order neurons extend from sensory receptors into the cord and up to the medulla oblongata on the same side of the body. The cell bodies of these neurons are in the dorsal root ganglia of the spinal nerves. Their axons form the posterior column: the fasciculus gracilis and the fasciculus cuneatus.

The axon terminals synapse with second order neurons in the medulla. The cell body of a second order neuron is located in the nucleus cuneatus or nucleus gracilis. The axon of the second order neuron crosses to the opposite side of the medulla and enters the medial lemniscus. This is a projection that extends from the medulla to the thalamus. However, because sensory pathways are three neuron pathways, the tract doesn't end in the thalamus. In the thalamus, the axon terminals of second order neurons synapse with third order neurons which go to the somatosensory area of the cerebral cortex.