Neuroanatomy Lecture Notes

Flashcards covering the anatomy of the meninges, ventricular system, cerebrum, diencephalon, limbic system, brainstem, and cerebellum.

Meninges

Three protective membranes surrounding the brain and spinal cord: Dura mater, Arachnoid mater, and Pia mater.

Dura Mater

Outermost, strongest layer of the meninges; provides protection and mechanical stability.

Epidural Space

Potential space between the dura mater and cranium.

Falx Cerebri

Largest dural fold; separates the right and left cerebral hemispheres.

Tentorium Cerebelli

Dural fold that separates the cerebrum and cerebellum.

Arachnoid Mater

Middle, delicate, transparent membrane of the meninges.

Subdural Space

Potential space beneath the dura mater.

Pia Mater

Innermost, highly vascular layer of the meninges.

Subarachnoid Space

Space between the arachnoid and pia mater, containing cerebrospinal fluid (CSF).

Ventricular System

Set of interconnected cavities in the brain that produce and circulate cerebrospinal fluid (CSF).

Lateral Ventricles

Located within each cerebral hemisphere.

Cerebral Aqueduct

Connects the third and fourth ventricles; passes through the midbrain.

Fourth Ventricle

Diamond-shaped cavity located posterior to the pons and anterior to the cerebellum.

Median Aperture (Foramen of Magendie)

Major CSF exit point from the fourth ventricle to the cisterna magna.

Lateral Apertures (Foramina of Luschka)

Major CSF exit points from the fourth ventricle to the cerebellopontine angle cistern.

Choroid Plexus

Vascular network of blood vessels and nerve cells within the ventricles that produces CSF.

Arachnoid Villi

Projections of the arachnoid through the dura mater where CSF is reabsorbed into the venous system.

Subarachnoid Cisterns

Widened areas of the subarachnoid space, mostly at the base of the brain, containing CSF and neurovascular structures.

Cisterna Magna

Cistern located between the cerebellum, medulla, and occipital bone; the largest cistern.

Interpeduncular Cistern

Cistern located between midbrain peduncles, connecting to the prepontine cistern.

Prepontine Cistern

Cistern located anterior/inferior to the pons.

Cerebellopontine Angle (CPA) Cistern

Cistern located between the pons and cerebellum; contains CN V, VII, VIII, AICA, and SCA.

Subarachnoid Hemorrhage (SAH)

Bleeding into the subarachnoid space.

Cerebrum

Largest part of the brain, divided into left and right cerebral hemispheres.

Gyri

Ridges on the surface of the cerebrum.

Sulci

Shallow grooves on the surface of the cerebrum.

Fissures

Deep grooves separating parts of the cerebrum.

Lateral Fissure (Sylvian Fissure)

Separates frontal and parietal lobes from the temporal lobe.

Gray Matter

Composed of neuron cell bodies; forms the cerebral cortex.

White Matter

Composed of myelinated axons and lies deep to the cortex.

Corpus Callosum

Largest and densest white matter tract in the cerebrum; connects the right and left cerebral hemispheres.

Anterior Commissure

Crosses midline in the lamina terminalis and connects anterior temporal lobes.

Posterior Commissure

Located posterior to the third ventricle and involved in pupillary light reflexes.

Frontal Lobe

Most anterior lobe of the cerebrum; functions include reasoning, judgment, emotions, and voluntary movement.

Parietal Lobe

Lobe located posterior to the central sulcus; functions include sensation, writing, and reading.

Occipital Lobe

Most posterior lobe; functions include visual perception.

Temporal Lobe

Lobe anterior to the occipital lobe; functions include auditory and olfactory processing and memory.

Insula (Island of Reil)

Lies deep within the lateral fissure and is thought to mediate sensory and motor functions of the viscera.

Basal Nuclei (Basal Ganglia)

Clusters of subcortical gray matter involved in planning and regulating motor activity.

Caudate Nucleus

Located adjacent to the lateral ventricles; divided into head, body, and tail.

Lentiform Nucleus

Shaped like a biconvex lens and located between the insula, caudate nucleus, and thalamus; divided into putamen and globus pallidus.

Claustrum

Thin, linear layer of gray matter located between the insula and lentiform nucleus; believed to be involved in visual attention.

Capsular Pathways

White matter tracts that separate and surround the basal nuclei.

Internal Capsule

Located between the caudate nucleus/thalamus and lentiform nucleus; a major communication pathway between the cerebral cortex and lower CNS structures.

External Capsule

Lies between the claustrum and lentiform nucleus for corticocortical communication.

Extreme Capsule

Located between the claustrum and insular cortex, facilitating cortical connections.

Diencephalon

A deep, central part of the brain located between the cerebrum and the midbrain; involved in sensory processing, endocrine regulation, and autonomic function.

Thalamus

Oval-shaped masses of gray matter on either side of the third ventricle; main relay center for sensory information traveling to the cerebral cortex.

Hypothalamus

Located just below the thalamus, forming the floor of the third ventricle; regulates activities of the autonomic nervous system, endocrine system, and limbic system.

Pituitary Gland (Hypophysis)

Small endocrine gland located at the base of the brain; controls many other endocrine glands.

Epithalamus

Most posterior part of the diencephalon; includes the pineal gland and posterior commissure.

Pineal Gland

Small endocrine structure that secretes melatonin, regulating the sleep-wake cycle.

Limbic System

Complex network of interconnected brain structures involved in emotional processing, memory, learning, and instinctual behaviors.

Hippocampus

Located deep within the parahippocampal gyrus on the medial side of the temporal lobe; responsible for converting short-term memory into long-term memory.

Amygdala

Almond-shaped mass of gray matter located anterior to the hippocampus; involved in emotional processing, particularly fear, anger, and sexual behavior.

Parahippocampal Gyrus

Forms the inrolled medial edge of the temporal lobe and contains the hippocampus and amygdala; critical for memory and emotional responses.

Fornix

Arch-shaped white matter tract located beneath the splenium of the corpus callosum; main output pathway of the hippocampus.

Cingulate Gyrus

Curved gyrus located above the corpus callosum on the medial surface of each cerebral hemisphere; significant role in emotional regulation and pain perception.

Mamillary Bodies

Two small, rounded structures found on the floor of the posterior hypothalamus; involved in memory processing and motivational behavior.

Brainstem

Connects the cerebral cortex, cerebellum, and spinal cord; contains vital motor and sensory nuclei and serves as the origin point for 10 of the 12 cranial nerves.

Midbrain (Mesencephalon)

Uppermost part of the brainstem; composed mainly of fiber tracts and divided into cerebral peduncles and tectum.

Cerebral Aqueduct

Passes through the midbrain, connecting the third and fourth ventricles.

Tectum

Roof of the midbrain; contains four colliculi (superior and inferior).

Cerebral Peduncles

Large bundles of motor fibers connecting the cerebral cortex to the spinal cord.

Substantia Nigra

Pigmented layer within the peduncles that produces dopamine.

Red Nucleus

Motor relay between the cerebellum and cerebral cortex; involved in coordination and balance.

Periaqueductal Gray Matter

Surrounds the cerebral aqueduct and processes pain and temperature signals.

Pons

Located between the midbrain and medulla oblongata; serves as a 'bridge' connecting the spinal cord to the cerebral cortex and more.

Medulla Oblongata

Extends from the pons down through the foramen magnum into the spinal cord; acts as the relay point for all motor and sensory tracts between the brain and spinal cord.

Medullary Pyramids

Located on either side of the anterior median fissure; contain motor fibers involved in voluntary movement.

Olives

Oval structures on the lateral surfaces of the medulla; contain nuclei involved in balance, coordination, and sound modulation.

Cerebellum

Located posteriorly to the brainstem within the posterior cranial fossa; coordination center for motor functions.

Cerebellar Hemispheres

Lateral portions of the cerebellum, connected by the vermis at the midline.

Cerebellar Tonsils

Rounded protrusions located on the inferior surface of the cerebellar hemispheres.

Cerebellar Peduncles

Three pairs of nerve tracts connecting the cerebellum to the brainstem.

Dentate Nucleus

Located deep within each cerebellar hemisphere; fibers project to the thalamus and influence motor control.

Arnold-Chiari Malformation

A defect involving the downward displacement or herniation of the cerebellum and brainstem through the foramen magnum.