Functional Anatomy of the Brain Descriptions (Exam 1) Flashcards
Frontal Lobe
programming motor patterns
learning and behavior
Occipital Lobe
Contain centers for vision (visual cortices)
Olfactory Lobe
Center for smell
Parietal Lobe
Touch, temperature, pressure, pain (nociception)
Conscious control of skeletal muscle activity
Piriform Lobe
Receive olfactory information (axons) via the olfactory tracts
Temporal Lobes
Centers for hearing (auditory cortices)
Diencephalon
Thalamus: receives, processes, relays to the cerebral cortex information from other regions of the brain and most sensory information (NO olfaction)
Hypothalamus: regulation of ANS and visceral and endocrine functions
Dorsal Metencephalon
Cerebellum
Controls the rate, range, and force of voluntary movements (does NOT initiate movements)
Mesencephalon
Midbrain
Control of motor functions, coordination of visual and auditory reflexes, processing of sensory information (auditory)
Myelencephalon
Medulla Oblongata
Autonomic functions
Arousal
Muscle tone for posture and movement
Telencephalon
Paired cerebral hemispheres
Cerebral Cortex: site of awareness, initiation of voluntary movements, and perception of stimuli
Basal Ganglia: planning and initiation of motor activities
Hippocampus: processing and storage of memories
Ventral Metencephalon
Pons
Conveys information about movement from the cerebrum to the cerebellum
Auditory Cortex
Acoustic area for conscious perception of sound
Motor Cortex
Neurons influence contralateral lower motor neurons innervating skeletal muscles
Neurons within the postcruciate gyrus influence appendicular musculature
Neurons with the rostral suprasylvian gyrus influence muscles of the neck and specific muscles of the head
Olfactory Cortex
Olfactory information is perceived, processed, and distributed to other parts of the brain within the piriform lobes
Visual Cortex
Vision
Somesthetic Cortex
Receive sensory information from defined regions of the body
Limbs and trunk
Abducent N.
Cranial Nerve VI
Innervates the retractor bulbi and lateral rectus muscles of the eyeball
Accessory N.
Cranial Nerve XI
Innervates muscles of the neck and forelimb that are of brachial arch origin
Facial N.
Cranial Nerve VII
Innervates the muscles of facial expression (superficial muscles of the head and face + the caudal belly of the digastricus, platysma, stylohyoid, and stapedius muscles)
Sensory for taste in the rostra 2/3 of tongue via chorda tympani nerve
Parasympathetic innervation to the mandibular and monostomatic part of the sublingual salivary glands and lacrimal gland
Glossopharyngeal N.
Cranial Nerve IX
Lingual and pharyngeal branches
Motor (somatic): m. stylopharyngeus + other pharyngeal mm
Parasympathetic: parotid and zygomatic salivary glands via otic ganglion
Sensory: taste, mechanoreception, thermoreception, nociception for caudal 1/3 of tongue
Hypoglossal N.
Cranial Nerve XII
Innervates intrinsic and extrinsic muscles of the tongue
Oculomotor N.
Cranial Nerve III
Arises from midbrain
Innervates dorsal, ventral, medial rectus muscles, ventral oblique muscle, and levator palpebrae superioris muscle
Provides parasympathetic innervation via the ciliary ganglion to constrict the pupil and round the lens
Optic N.
Cranial Nerve II
Nerves of sight
Nerve fibers originate as axons of ganglion neurons of the retina, leave the eye via optic disk and form optic nerve
Trigeminal N.
Cranial Nerve V
Muscles of mastication and skin of face
Ophthalmic N.
Maxillary N.
Mandibular N.
Ophthalmic N.
Branch of trigeminal n.
Sensory to eyeball skin of forehead, caudal muzzle, medial canthus of eye, nasal mucosa
Maxillary N.
Sensory to upper jaw (lateral canthus of eye, nose, upper lip, cheek, mucosa of tongue, oral vestibule, floor of mouth) and temporal and zygomatic regions (skin, external acoustic meatus, tympanic membrane, parotid salivary gland, guttural pouch in horse)
Mandibular N.
Motor to muscles of mastication (masseter, temporalis, medial and lateral pterygoid, mylohyoid, rostral belly of digastricus)
Sensory to lower jaw (skin of chin, lower lips, mandibular teeth, mucosa of tongue, oral vestibule, floor of mouth) and temporal and zygomatic regions
Vagus N.
Cranial Nerve X
Innervates the muscles of the pharynx, larynx, and esophagus
Contains visceral afferents from the pharynx, larynx, and esophagus
Innervates taste buds of the palate and pharynx
Innervates thoracic and abdominal visceral (parasympathetic)
Contains afferents from the skin of the external ear canal
Vestibulocochlear N.
Cranial Nerve VIII
Hearing (cochlear)
Balance and equilibrium (vestibular)
Arbor Vitae
White matter tracts visibly seen branching within the gray matter of the cerebellum
Brachium of the Caudal Colliculus
Functions in relay of auditory information
Caudal Colliculus
auditory
Cerebellar Peduncle
connects the cerebellum with the brain stem
Cerebellum
Responsible for controlling the rate, range, and force of voluntary movements
Does NOT initiate or direct voluntary movements
Columns of the Fornix
Carry axons that originated from neurons in the hippocampus to the mamillary bodies
Commissure of the Caudal Colliculus
Bundle of transverse fibers that connects the caudal colliculi
Corpus Callosum
connects the cerebral cortices
Cruciate Sulcus
Serve as landmarks designating the rostral extent of the primary motor and somesthetic cortexes
Crus Cerebri
Upper motor neurons that influence the activity of lower motor neurons in the brain stem and spinal cord
Fasciculus Cuneatus
General proprioceptive information from the thoracic limbs, cranial trunk region, and the neck
Fasciculus Gracilis
General propioceptive information from the caudal trunk and pelvic limb
Hypophysis
Pituitary Gland
Hormonal Secretions
Internal Capsule
Composed of fibers from thalamic nuclei that travel to the cerebral cortex and of fibers from projection neurons in the cerebral cortex that travel to the brain and spinal cord
Thalamus
Contains nuclei that relay information to the cerebral cortices
Interventricular Foramen
Connection between a lateral ventricle and the third ventricle
Lateral Geniculate Body
Nucleus of the thalamus which receives information from the retinae (via optic tracts) and projects axons to the visual cortex of the cerebrum
Lateral Olfactory Tract
Bundles of fibers that carry olfactory information from the olfactory bulbs to the piriform lobes of the cerebrum
Lateral Rhinal Sulcus
Delineates the olfactory portions of the brain from the rest of the cerebral hemispheres
Longitudinal Fissure
Divides the cerebrum into two cerebral hemispheres along the midline
Mamillary Body
Part of the limbic system (behavior)
Medial Geniculate Body
Nucleus of the thalamus which receives auditory information from the lower auditory centers via the caudal colliculus and projects axons into the auditory cortex of the cerebrum
Medial Olfactory Tract
Bundles of fibers that carry olfactory information from the olfactory bulbs to the piriform lobes of the cerebrum
Median Sulcus
Marks the midline in the rhomboid fossa
Medulla Oblongata
Myelencephalon
ANS
Arousal
Muscle tone and movement
Mesencephalic Aqueduct
Connects the third and fourth ventricles
Occipital Gyrus
Part of the visual cortex
Olfactory Bulb
Receives special visceral afferent (SVA) fibers from olfactory epithelium via the foramina in the cribiform plate
Olfactory primary afferents synapse on second order neurons in the olfactory bulb
Olfactory Peduncle
Joins the olfactory bulb to the cerebral hemisphere, courses caudad with a band of fibers on its ventral surface which further bifurcates into the lateral and medial olfactory tracts
Relay axons travel through these tracts to the piriform lobe of the cerebrum
Optic Tract
Composed of axons that synapse on neurons in the lateral geniculate nucleus for relay to the visual cortex and on neurons in the rostral colliculus for visual-evoked reflexes involving movement of the head, neck, and eyeballs
Pineal Gland
Epiphysis
Established reproductive cycles in response to photoperiod
Produces melatonin in response to darkness
Pons
Conveys information about movement from the cerebrum to the cerebellum
Postcruciate Gyri
Serve as landmarks designating the “primary motor areas” for the motor cortices and somesthetic cortices of the parietal lones
Pyramid
Contains axons of neurons found in the motor cortex as part of the upper motor pathway which influences the activity of the lower motor neurons in the brain stem cranial nerve motor nuclei and in the ventral horn of the spinal cord to produce voluntary movements
Rostral Colliculus
Dorsal eminence of the midbrain whose neurons receive sensory information from the visual system (via optic n.), spinal cord, and cerebral cortex
Functions in the regulation of unconscious reflex responses to visual stimuli (head, neck, eye movements)
Rostral Commissure
Composed of axons that course between olfactory structures on each side of the cerebrum
Septum Pellucidum
separates lateral venticles
Sulcus Limitans
Differentiates floor and wall of the fourth ventricle
Thalamus
Receives, processes, and relays to the cerebral cortex information from other regions of the brain and most sensory information (NOT olfaction)
Third Ventricle
Communicates with the lateral ventricles via the interventricular foramina and with the fourth ventricle via the mesencephalic aqueduct
Transverse Cerebral Fissure
Separates the cerebrum from the cerebellum
Trapezoid Body
auditory system
Tuber Cinereum
Forms the central part of the hypothalamus to which the hypophysis (pituitary) is attached via the infundibulum
Cerebellar Peduncle
Paired fiber bundles which connect the cerebellum with the brain stem
Flocculonodular Lobe
Maintenance of equilibrium and coordination
Primary Fissure
Divides the cerebellar body into rostral and caudal lobes
Vermis
Midline of the cerebellum
Receives input from the vestibular apparatus and proprioceptors of the trunk and proximal limbs
Caudate Nucleus
Initiation of voluntary movements
Choroid Plexus
One site of cerebral spinal fluid (CSF) production
Columns of the Fornix
Ventrorostral extensions of the body of the fornix that carry the axons that originated from neurons in the hippocampus to the mamillary bodies
Fornix
Composed of axons that originate from neurons in the hippocampus and project through the columns of the fornix to reach the mamillary bodies
Floor of Lateral Ventricle
Choroid plexus in the floor produces CSF
Hippocampus
Limbic system (memory storage)
Interventricular Foramen
Connection between a lateral ventricle and the third ventricle
Rostral Commissure
olfaction
Trochlear N.
Cranial Nerve IV
Only cranial nerve to arise from the dorsal aspect of the brain stem and cross entirely to innervate contralateral side
Motor to dorsal oblique muscle