Ct sectional anatomy ch.3

Anterior cerebral arteries

Branches of the internal carotid arteries located in the anterior portion of the longitudinal fissure of the cerebrum

Arachnoid

The thin cobweb-appearing layer of the meninges, located between the dura mater and pia mater

Basal ganglia

Clusters of gray matter located within the white matter of each cerebral hemisphere; also called cerebral nuclei

Basilar artery

Artery in the pontine cistern that receives blood from the vertebral arteries and carries this blood into the circle of Willis at the base of the brain

Brainstem

Portion of the brain that connects the cerebrum and spinal cord; consists of the midbrain, the pons, and the medulla oblongata

C-1 and C-2

The first two cervical vertebrae; C1 is the atlas and C2 is the axis

Caudate nucleus

A mass of gray matter located adjacent to the lateral ventricles in the cerebrum

Cavernous sinus

A space, or cavity, on either side of the dorsum sellae of the sphenoid bone

Cerebellar peduncle

Bundle of nerve fibers that connects the cerebellum with other parts of the central nervous system

Cerebellomedullary cistern

Subarachnoid space between the cerebellum and the medulla oblongata; also called the cisterna magna

Cerebellum

Portion of the brain that is posterior and inferior to the cerebrum and functions in the coordination of movements

Cerebral aqueduct

Channel for cerebrospinal fluid between the third and fourth ventricles in the brain; passes through the midbrain; also called the aqueduct of Sylvius

Cerebral peduncles

Two bands of fibers on the ventral aspect of the midbrain that contain voluntary motor tracts descending from the cerebral cortex

Cerebrospinal fluid

A fluid that is produced by the choroid plexus of the ventricles and circulates through the ventricles of the brain and in the subarachnoid space around the brain

Cerebrum

The largest part of the brain, consisting of two hemispheres

Choroid plexus

Specialized vascular structures that produce cerebrospinal fluid in the ventricles of the brain

Circulus arteriosus cerebri

Circle of anastomosing arteries at the base of the brain; also called the circle of Willis

Cisterna ambiens

The subarachnoid space at the posterior end of the corpus callosum; also called the superior cistern or the cistern of the great cerebral vein

Corpora quadrigemina

Four bodies that form the dorsal part of the midbrain

Corpus callosum

A large band of white fibers that connects the two cerebral hemispheres

Diencephalon

Portion of the brain that is surrounded by the cerebral hemispheres and that encloses the third ventricle; principal components are the thalamus and hypothalamus

Dura mater

The outer, tough covering around the brain and spinal cord; the outer layer of the meninges

Epicranial aponeurosis

The broad flat sheet of tendon that connects the frontalis and occipitalis muscles on the top of the skull; also called the galea aponeurotica

Falx cerebelli

The triangular extension of the cranial dura mater that is located between the two lobes of the cerebellum

Falx cerebri

The fold of cranial dura mater that extends into the longitudinal fissure between the two cerebral hemispheres

Fourth ventricle

Space that contains cerebrospinal fluid and is located at the level of the pons and cerebellum

Frontal lobe

The portion of the cerebrum that is located in the anterior cranial fossa and is anterior to the central sulcus

Hypophysis

Endocrine gland attached to the hypothalamus of the brain by the infundibulum; also called the pituitary gland

Inferior sagittal sinus

Triangular space that contains cerebrospinal fluid and is located in the inferior margin of the falx cerebri

Insula

The hidden lobe of the brain, deep to the temporal lobe; also called the island of Reil

Internal capsule

Band of white fibers lateral to the caudate nucleus and thalamus but medial to the lentiform nucleus in the cerebrum

Internal carotid artery

Branch of the common carotid artery that passes through the carotid canal to the inferior surface of the brain, then branches into the anterior and middle cerebral arteries

Internal jugular vein

Major vessel that drains blood from the brain; joins the subclavian vein to form the brachiocephalic vein

Interventricular foramen

Opening located between a lateral ventricle and the third ventricle; also called the foramen of Monro

Lateral fissure (sulcus)

Deep cleft that separates the temporal lobe of the cerebrum from the parietal lobe

Lateral ventricles

Large cavities within the cerebrum that contain cerebrospinal fluid; consist of body, anterior and posterior horns

Lentiform nucleus

A mass of gray matter, lateral to the internal capsule, that is a part of the basal ganglia

Longitudinal fissure

Cleft of the brain that separates the cerebrum into two cerebral hemispheres

Mammillary bodies

Rounded structures located at the base of the hypothalamus

Masseter muscle

The muscle that acts to close the jaw, a muscle of mastication

Medulla oblongata

Most inferior portion of the brainstem; extends from the pons to the spinal cord and is continuous with the spinal cord at the foramen magnum

Meninges

Membranes that cover the brain and the spinal cord

Middle cerebral arteries

Branches of the internal carotid arteries located in the lateral fissure of the cerebrum

Occipital lobe

Most posterior lobe of the cerebrum; located in the posterior cranial fossa

Optic chiasma

Region, just anterior to the pituitary gland, where the right and left optic nerves meet and some fibers cross over to the opposite side

Optic nerves

Bundles of nerve fibers that carry visual impulses from the retina of the eye to the optic chiasma

Optic tracts

Bundles of fibers in the visual pathway between the optic chiasma and the thalamus

Parietal lobe

Portion of the cerebrum that is immediately posterior to the central sulcus

Parotid gland

Largest of the salivary glands; located between the ramus of the mandible and the external auditory meatus

Pharynx

A musculomembranous tube posterior to the nasal, oral, and laryngeal cavities

Pia mater

A delicate membrane, the innermost layer of meninges around the brain

Pineal body

A region of the epithalamus in the diencephalon that is thought to be involved with regulating the 'biological clock'; also called the pineal gland because it secretes melatonin

Pons

Central part of the brainstem, located between the cerebral peduncles and the medulla oblongata

Pontine cistern

Subarachnoid space anterior to the pons; contains the basilar artery

Septum pellucidum

A thin partition between the two lateral ventricles in the brain

Sigmoid sinus

S-shaped channel that passes through the petrous portion of the temporal bone and drains blood and cerebrospinal fluid into the internal jugular vein

Sphenoid sinus

Air-filled cavity in the sphenoid bone; one of the paranasal sinuses

Spinal cord

Part of the central nervous system that extends inferiorly from the medulla oblongata and is located within the vertebral canal

Sternocleidomastoid muscle

Straplike muscle that originates on manubrium of the sternum and clavicle and inserts on the mastoid process of the temporal bone

Straight sinus

A venous channel that passes along the tentorium cerebelli from the inferior sagittal sinus to the confluence of sinuses

Subarachnoid space

The space between the arachnoid and pia mater layers of the meninges; contains cerebrospinal fluid

Superior cistern

Subarachnoid space between the splenium of the corpus callosum and the cerebellum and contains the great cerebral vein

Superior sagittal sinus

Triangular venous channel along the superior margin of the falx cerebri

Tentorium cerebelli

An extension of dura mater that acts as a partition between the cerebrum and the cerebellum

Thalamus

An oval mass of gray matter, located on either side of the third ventricle in the cerebrum; primarily functions as a relay center for sensory impulses

Third ventricle

Single midline space that contains cerebrospinal fluid in the center of the cerebrum

Transverse sinus

Venous channel that extends laterally from the confluence of sinuses to the sigmoid sinus

Trigeminal nerve

Cranial nerve V

Vertebral arteries

Branches of the subclavian arteries that ascend the neck in the transverse foramina of cervical vertebrae, then pass through the foramen magnum to supply the posterior portion of the brain

Vitreous humor

Jellylike substance that fills the posterior cavity of the eye, between the lens and the retina; also called vitreous body