Internal arcuate fibers are the axon

Axon

An axon is a long, slender projection of a nerve cell, or neuron, that conducts electrical impulses away from the neuron's cell body or soma....

s of second-order neuron

Neuron

A neuron is an electrically excitable cell that processes and transmits information by electrical and chemical signaling. Chemical signaling occurs via synapses, specialized connections with other cells. Neurons connect to each other to form networks. Neurons are the core components of the nervous...

s contained within the gracile

Gracile nucleus

Located in the medulla oblongata, the gracile nucleus is one of the dorsal column nuclei that participate in the sensation of fine touch and proprioception of the lower body...

 and cuneate nuclei

Cuneate nucleus

One of the dorsal column nuclei, the cuneate nucleus is a wedge-shaped nucleus in the closed part of the medulla oblongata. It contains cells that give rise to the cuneate tubercle, visible on the posterior aspect of the medulla...

 of the medulla oblongata

Medulla oblongata

The medulla oblongata is the lower half of the brainstem. In discussions of neurology and similar contexts where no ambiguity will result, it is often referred to as simply the medulla...

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These fibers cross (decussate) from one side of the medulla to the other to form the medial lemniscus

Medial lemniscus

The medial lemniscus, also known as Reil's band or Reil's ribbon, is a pathway in the brainstem that carries sensory information from the gracile and cuneate nuclei to the thalamus.-Path:...

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Part of the dorsal column-medial lemniscus system (second neuron), the internal arcuate fibers are important for relaying the sensation of fine touch and proprioception

Proprioception

Proprioception , from Latin proprius, meaning "one's own" and perception, is the sense of the relative position of neighbouring parts of the body and strength of effort being employed in movement...

 to the thalamus

Thalamus

The thalamus is a midline paired symmetrical structure within the brains of vertebrates, including humans. It is situated between the cerebral cortex and midbrain, both in terms of location and neurological connections...

 and ultimately to the cerebral cortex

Cerebral cortex

The cerebral cortex is a sheet of neural tissue that is outermost to the cerebrum of the mammalian brain. It plays a key role in memory, attention, perceptual awareness, thought, language, and consciousness. It is constituted of up to six horizontal layers, each of which has a different...

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External links

• Photo at Indiana.edu