Anatomy ch 13
Cerebellum
Attached to the brainstem posterior to the pons. Communicates with other regions of cns through superior, middle, and inferior cerebellar peduncles
Reticular formation
A diffuse system consisting of several loosely packed nuclei scattered throughout the length of the brainstem. Functions involve cycles of activity such as sleep-wake cycle
3 categories of fibers
Association, commissural, projection
Occulomotor III
Innervates 4 of 6 muscles that move eyeball, adjusts pupil size
Inferior colliculi
Involved in hearing
Longitudinal fissure
Divides left and right hemispheres
Colliculus
Each mound of the tectum
Olfactory I and optic II
Exclusively sensory
Cerebrospinal fluid
Fills subarachnoid space
3 parts of cerebellum
Flocculonoclular lobe, vermis, 2 lateral hemispheres
Gyri
Fold on surface of hemispheres (gray matter on outer surface of cerebrum)
Pyraminds
Two prominent enlargements on the anterior surface of medulla oblongata
Olives
Two rounded oval structures protrude from the anterior surface of the medulla oblongata; nuclei involved in functions such as balance, coordination, and modulation of sound from the inner ear
Cerebral medulla
White matter of brain between cortex and nuclei; consists of tracts that connect areas of cerebral cortex to each other and other areas of cns
Arbor vitae
White matter of cerebellum
Commissural fibers
White matter that connects left and right hemispheres
Tectum
(Roof) consists of 4 nuclei that form mounds on the dorsal surface
Thalamus
Cluster of nuclei; has 2 large, lateral portions connected in the center by a small stalk called the interthalamic adhesion (intermediate mass), influences mood and actions associated with strong emotions
Neural plate
Cns develops from thsi
Meninges
Connective tissue membranes that surround and protect the brain and spinal cord
Tegmentum
Consists of ascending tracts which carry sensory information from the spinal cord to the brain
Cerebral peduncles
Constitute the portion of the midbrain ventral to the tegmentum
Facial VII
Controls all muscles of facial expression
Trigeminal V
Greatest sensory function
Sulci
Grooves between gyri
Basal nuclei
Group of functionally related nuclei located bilaterally in the inferior cerebrum, diencephalon, and midbrain; involved in control of motor functions
Brainstem
Medulla oblongata, pons, midbrain; connects spinal cord to remainder of brain; responsible for many essential functions; damage is fatal
Medulla oblongata
Most inferior part of brain stem, contains sensory and motor tracts, part of reticular formation
Hypothalamus
Most inferior; mammillary bodies appear as bulges on the ventral surface; involved in olfactory reflexes and emotional responses to odor; eating disorder, intense thirst, varying body temps are dysfunction of this
Dura mater
Most superficial meningeal layer
Decussate
Nerve fibers that cross from one side of the nervous system to the other
Pons
Part of brain stem just superior to the medulla oblongata; connects the medulla to the midbrain; contains ascending and descending tracts; relays info from the cerebrum to the cerebellum; involved in controlling respiration along with the medulla oblongata
Diencephalon
Part of the brain located between the brainstem and the cerebrum; consists of the thalamus, subthalamus, epithalamus, hypothalamus
Limbic system
Parts of cerebrum and diencephalon; plays central role in survival functions and emotional interpretation of sensory input
Dropping of upper eyelid
Ptosis, damage to occulomotor
Superior colliculi
Receive input from the eyes, skin, cerebrum, and inferior colliculi. Involved in visual reflexes which control the movement of the head, eyes, and body toward a visual, auditory, or tactile stimuli
Cranial nerves organized by
Roman numerals from anterior to posterior
Central sulcus
Separates frontal and parietal lobes
Lateral fissure
Separates temporal lobe from rest of cerebrum
Subthalamus
Small area inferior to thalamus that contains several ascending and descending tracts and the subthalamic nuclei, involved in controlling motor functions
Epithalamus
Small area superior and posterior to thalamus, consists of habenular nuclei and the pineal body (onset of puberty)
Midbrain or mesencephalon
Smallest region of brain stem; located just superior to the pons and contains the nuclei of cranial nerves
Lateral cerebellar peduncles
Smooth flowing movements, fine motor coordination
Infundibulum
Stalk that extends from floor of hypothalamus and connects it to the posterior pituitary gland (hypophysis)
Glossopharyngeal
Taste