Nervous System and Cranial Nerves Flashcards

Flashcards covering the nervous system, sensory and motor pathways, and cranial nerve anatomy.

Peripheral Nervous System

Part of the nervous system that includes all the nerves outside of the brain and spinal cord.

Somatosensory Information

Sensory information from the skin to the brain about touch, proprioception, pain, and temperature.

Dorsal Column Medial Lemniscus

An ascending pathway that carries information about touch and proprioception.

Gracilis and Fasciculus Cuneatus

First, second, and third-order neurons relaying touch and proprioceptive information from the lower or upper half of the body

Anterolateral System

An ascending pathway that carries information about pain and temperature.

Dorsal Root

The location where sensory information enters the spinal cord.

Decussation

The point where nerve pathways cross over to the opposite side of the central nervous system.

Spinothalamic Tract

Another name for the anterolateral system region, referring to its path from the spinal cord to the thalamus.

Primary Somatosensory Cortex (S1)

The area in the postcentral gyrus that receives sensory information from the thalamus.

Corticospinal Tract

The pathway that carries motor signals from the primary motor cortex down the spinal cord to the muscles.

Decussation of the Pyramids

The location in the medulla where the corticospinal tract crosses over.

Lower Motor Neuron

The neuron that directly innervates muscles and has its cell body in the ventral horn of the spinal cord.

Ventral Root

The bundle of axons that carries motor neuron signals away from the spinal cord.

Primary Motor Cortex (M1)

Located in the precentral gyrus and is organized with a body map (somatotopy) related to fine motor control.

Basal Nuclei

Deep clusters of nuclei within the cerebrum (caudate, putamen, and globus pallidus) that act as a gas for the voluntary movement and breaks for involuntary movements.

Cerebellum

Monitors movement, comparing intended movement to actual movement, and corrects errors for motor learning.

Spinal Nerves

Nerves emerging from the spinal cord that connect the spinal cord to targets below the head and neck, carrying both sensory and motor information.

Mixed Nerves

Nerves containing both sensory and motor axons.

Cranial Nerves

12 pairs of nerves that originate from the brain, mostly innervating the head and neck, and can be sensory, motor, or both.

Optic Nerve

Cranial nerve II, which is sensory and carries visual information from the retina to the primary visual cortex.

Oculomotor, Trochlear, and Abducens Nerves

Cranial nerves III, IV, and VI, which control eye movements.

Trigeminal Nerve

Cranial nerve V, which is both sensory (sensation of the face) and motor (muscles of mastication).

Facial Nerve

Cranial nerve VII, which is both sensory (taste) and motor (muscles of facial expression).

Vestibulocochlear Nerve

Cranial nerve VIII, which is sensory and carries information related to hearing (cochlea) and balance (vestibular organs).

Glossopharyngeal Nerve

Cranial nerve IX, which is both sensory (taste from the tongue) and motor (pharynx muscles).

Vagus Nerve

Cranial nerve X, which is both sensory and motor and has functions throughout the body.

Accessory Nerve

Cranial nerve XI, which is motor and controls neck muscles.

Hypoglossal Nerve

Cranial nerve XII, which is motor and controls tongue muscles.