Nervous System Lab: Spinal Cord, Brain, and Cranial Nerves

Vocabulary flashcards covering the structures, regions, and functions of the spinal cord, brain, and cranial nerves from Chapters 14 and 16.

Filum terminal

A fibrous extension extending from the conus medullaris to the coccyx.

Denticulate ligaments

Lateral extensions of pia mater that connect to the dura mater and prevent excessive movement of the spinal cord.

Conus medullaris

The tapered end of the spinal cord located at or near L1-L2.

Cauda equina

The continuation of lumbar, sacral, and coccygeal nerve roots beyond the conus medullaris.

Dorsal root

The portion of a spinal nerve containing sensory axons.

Dorsal root ganglion

A swelling on the dorsal root containing sensory cell bodies.

Ventral root

The portion of a spinal nerve containing visceral and somatic motor axons.

Spinal nerve

A peripheral nerve formed by the fusion of a dorsal root and a ventral root.

Cervical plexus

Nerve plexus formed by C1-C4 and some of C5 that innervates muscles of the neck and diaphragm, and includes the phrenic nerve.

Brachial plexus

Nerve plexus formed by C5-T1 that innervates the pectoral girdle and upper limb, and includes the axillary nerve.

Lumbar plexus

Nerve plexus formed by T12-L4 that innervates the pelvis and lower limbs, and includes the femoral nerve.

Sacral plexus

Nerve plexus formed by L4-S4 that innervates the pelvis and lower limbs, and includes the sciatic nerve.

Ventricles

Cavities in the brain filled with cerebrospinal fluid produced by choroid plexuses.

Medulla oblongata

Major brain division connecting the brain with the spinal cord, containing pyramids and olives.

Pyramids

Structures of the medulla oblongata that contain motor tracts.

Olive

Swellings located lateral to the pyramids in the medulla oblongata.

Pons

Brain division containing nuclei concerned with involuntary control of respiration, as well as sensory and motor nuclei for cranial nerves V-VIII.

Mesencephalon

The midbrain; contains nuclei that process visual and auditory stimuli.

Corpora quadrigemina

Four nuclei comprising the tectum (roof) of the midbrain, composed of two pairs of sensory nuclei: superior colliculi and inferior colliculi.

Superior colliculi

Paired sensory nuclei of the corpora quadrigemina involved in vision.

Inferior colliculi

Paired sensory nuclei of the corpora quadrigemina involved in hearing.

Cerebral peduncles

Structures in the mesencephalon containing ascending and descending fiber tracts passing to and from the cerebrum.

Diencephalon

Deep region of the brain that connects the cerebrum to the rest of the brainstem; includes the epithalamus, thalamus, and hypothalamus.

Epithalamus

Roof of the third ventricle containing the choroid plexus of the 3rd ventricle and the pineal gland.

Pineal gland

Endocrine structure located in the epithalamus that produces melatonin.

Thalamus

Brain structure making up 80% of the diencephalon, consisting of about 12 nuclei types, and functioning as an important relay center for sensory and motor pathways.

Interthalamic adhesion

Also called the intermediate mass; connects the two thalamic masses.

Hypothalamus

Main visceral control center for homeostasis that regulates autonomic control, emotion, temperature, hunger, water balance, thirst, sleep/wake cycles, and endocrine function, linking the nervous and endocrine systems.

Pituitary gland

The 'master gland' (hypophysis), connected to the hypothalamus by the infundibulum and seated in the sella turcica on the sphenoid.

Optic chiasm

Structure where some fibers of the optic nerves from the eyes cross, allowing optic tracts to travel posteriorly to the brain.

Cerebellum

Region of the brain that regulates and coordinates muscular activity.

Vermis

Ridge of cerebellar cortex that separates the cerebellar hemispheres.

Arbor vitae

White matter of the cerebellum connecting the cerebellar cortex and cerebellar peduncles.

Cerebellar peduncles

Fiber tracts that link the cerebellum with the brain stem, cerebrum, and spinal cord.

Cerebrum

Also termed telencephalon; center for conscious thought, intellectual functions, and memory, where regulation of skeletal muscle contraction originates.

Longitudinal fissure

Deep groove that separates the right and left cerebral hemispheres.

Gyrus

A ridge of gray matter on the cerebral cortex.

Sulcus

A depression in the gray matter on the cerebral cortex.

Corpus callosum

The largest commissure composed of white matter that connects the cerebral hemispheres.

Anterior commissure

A prominent commissure of white matter linking the cerebral hemispheres.

Septum pellucidum

Thin medial partition separating the two lateral ventricles.

Limbic System

A functional division consisting of nuclei and tracts along the border between the cerebrum and diencephalon.

Fornix

A tract of white matter that connects the hippocampus with the hypothalamus.

Mamillary bodies

Structures located on the floor of the hypothalamus that control reflex movements associated with eating.

Brain Stem

Processing centers composed of the diencephalon, mesencephalon, pons, and medulla oblongata that relay information to and from the cerebrum and cerebellum.

Cranial Nerve I (Olfactory)

Sensory nerve originating from olfactory receptors.

Cranial Nerve II (Optic)

Sensory nerve originating from the retina.

Cranial Nerve III (Oculomotor)

Motor nerve originating in the midbrain.

Cranial Nerve IV (Trochlear)

Motor nerve originating in the midbrain.

Cranial Nerve V (Trigeminal)

Mixed nerve originating in the pons and general sensory receptors of the face.

Cranial Nerve VI (Abducens)

Motor nerve originating in the pons.

Cranial Nerve VII (Facial)

Mixed nerve originating in the pons and taste receptors.

Cranial Nerve VIII (Vestibulocochlear)

Sensory nerve originating from inner ear receptors.

Cranial Nerve IX (Glossopharyngeal)

Mixed nerve originating in the medulla oblongata and taste receptors.

Cranial Nerve X (Vagus)

Mixed nerve originating in the medulla oblongata and visceral sensory receptors.

Cranial Nerve XI (Accessory)

Motor nerve originating in the medulla oblongata.

Cranial Nerve XII (Hypoglossal)

Motor nerve originating in the medulla oblongata.