Ch. 16 Brain Flashcards
Function of the Brain
Nerve tracts: Myelinated; white matter
Bring information into the brain (sensory)
Transport information out of the brain (motor)
Transport information among the centers of the brain
Nuclei
Small centers of brain function; processing non-myelinated, gray matter
Sort incoming information or outgoing information into the appropriate areas or nerves
Cerebellum
Function: Muscle coordination.
Consists of arbor vitae, folia, anterior and posterior lobes
Cerebrum
Process sensory information, speech and language, emotions, etc.
Ventricles
Interventricular foramen
Lateral (anterior, posterior, inferior)
Third
Brain Stem
Midbrain, pons, medulla oblongata
Medulla Oblongata
Contains nuclei for processing of basic information Cranial nerves (V, IX, X, XI, XII) Heart rate Respiration Swallowing Vomiting Coughing Sneezing
Structures: Pyramids, decussate, olive
Pons
- Contains ascending and descending nerve tracts
- Nuclei relay information to cerebrum and cerebellum
- Nuclei for cranial nerves (V, VI, VII, VIII, IX)
- Sleep center and respiratory center
Midbrain (mesencephalon) Structures
Tectum, Tegmentum, Superior colliculus, Medial lemniscus, Red nucleus
Reticular formation
Several nuclei in the brain stem
Regulate cycles such as the sleep cycle
Cerebrospinal fluid
- Similar to blood serum without the proteins
- Circulation in the brain (nutrients, waste and signals)
- Cushioning for the brain
- Blood brain barrier prevents movement of most molecules into the CSF
Meninges (Surface to Deep)
Protective Coverings:
- Dura Mater
- Subdural space
- Arachnoid Mater
- Subarachnoid space
- Pia Mater
Dura mater
Very tough connective tissue; dense irregular connective tissue. Bound to bones of skull
Arachnoid mater
Wispy, spider-web like
Pia mater
Membrane bound to surface of brain
Subdural space
Small space containing serous fluid
Subarachnoid space
Blood vessels present, contains cerebrospinal fluid
Choroid plexus
Highly permeable capillaries in the ventricles.
Blood brain barrier
Astrocytes wrap around capillaries and tightly control the environment of the neurons.
Pyramids
Structure on Medulla Oblongata
Descending nerve tracts for control of skeletal muscles
Decussate
Structure on Medulla Oblongata
Forms an X in nerve tracts. Brain hemispheres control opposite side of the body
Olive
Structure on Medulla Oblongata
Nuclei involved in Balance, Coordination, Sound from ear
Tectum
Structure in the midbrain
consists of quadrigemina colliculus:
- Two superior colliculi: Visual reflexes (head turns toward light)
- Two inferior colliculi: Auditory reflex (head turns toward sound)
Tegmentum
Structure in the midbrain
carries information from spinal cord to brain
Red nuclei
Structure in the midbrain
Regulate and coordinate motor activities
Cerebral peduncle
Structure in the midbrain
Descending tracts carrying motor
information from the cerebrum to the spinal cord
Superior, middle and inferior peduncles
Structure of the cerebellum
Nerve tracts connect the cerebellum to the brain stem
Folia
Structure of the cerebellum
Ridges in the cerebellar cortex
Arbor vitae
Structure of the cerebellum
White matter (nerve tracts)
The flocculonodular lobe
Structure of the cerebellum
Balance and eye movement
Medial portion of hemispheres
Structure of the cerebellum
Posture, locomotion and fine motor control
Lateral hemispheres
Structure of the cerebellum
planning, practice and learning complex movement
Diencephalon Structures
- Corpus callosum
- Pineal gland
- Pituitary gland
- Thalamus
- Hypothalamus
- Epithalamus
- Subthalamus
Thalamus
ALL sensory neurons (except olfaction) go through the thalamus projections into the cerebral cortex
i. e.
- Medial geniculate nucleus: Auditory
- Lateral geniculate nucleus: Visual
- Ventral posterior nucleus: Other sensory
- Ventral anterior and posterior nuclei: Motor function
- Anterior and medial nuclei: Fear, rage through limbic
- Lateral dorsal nucleus: Emotions
- Lateral posterior and pulvinar nuclei: Sensory
Subthalamus
- Contains nerve tracts (ascending and descending)
- Subthalamic nuclei: Control motor functions
Epithalamus
- Habenular nuclei: Emotional response to odors
- Pineal gland: Onset of puberty? Sleep cycle
Hypothalamus (Structures)
- Mammillary bodies
- Infundibulum
- Pituitary gland
Hypothalamus (Functions)
- Autonomic: Heart rate, urine release, digestive movement, blood vessel diameter
- Endocrine: Central control for the endocrine system
- Muscle control: Swallowing and shivering
- Body temperature: Sweat, shivering, where aspirin reduces fever
- Food and water intake: Hunger and thirst centers
- Emotions: Fear and rage
- Sleep cycle: Jet lag?
Cerebrum (Some Structures)
- Sulcus and gyrus
- Cerebral cortex (surface)
- Cerebral medula (deep)
Cerebrum Fibers
Commissural fibers: Corpus callosum, connects right and left hemispheres
Association fibers: Connections within a hemisphere
Projection fibers: connections to spinal cord
Limbic system
Cerebrum and diencephalon
Function: Memory, reproduction, nutrition, emotions
Olfactory Nerve (I)
Sensory nerves associated with smell
Goes from the inside of the nasal cavity to the olfactory bulb
Optic nerve (II)
Sensory nerves associated with vision
Goes through the optic foramen/canal
Oculomotor nerve (III)
Motor neurons to most of the muscles that move the eye
Parasympathetic (autonomic) to the sphincter of the pupil and ciliary muscle of the lens
Goes through the superior orbital fissure
Trochlear nerve (IV)
Motor neuron for one muscle (superior oblique) in the eye (as opposed to four like the other nerve)
Named trochlear because of where the muscle connects, the trochlea
Goes through the superior orbital fissure
Trigeminal (V)
Tri = three major nerve branches: forehead, maxilla, and mandible
Mixed motor and sensory neurons
Ophthalmic branch
Trigeminal
Superior orbital fissure
Sensory from scalp and forehead
Maxillary branch
Trigeminal
Foramen rotundum
Sensory from upper jaw, teeth, nasal cavity, upper lip
Mandibular branch
Trigeminal
Foramen ovale
Sensory from lower jaw, teeth, tongue, chin, temporal region
Motor to masseter, temporalis, digastric, etc.
Abducent nerve (VI)
Motor neuron to the lateral rectus muscle of the eye (abducts the eye)
Facial nerve (VII)
Internal auditory meatus and Stylomastoid foramen
Sensory for taste, external ear, palate
Motor function for facial muscles, facial expression
Parasympathetic to submandibular and sublingual salivary glands, lacrimal gland, glands in nasal cavity
Vestibulocochlear nerve (VIII)
Internal auditory meatus
Sensory for hearing and balance
(Cochlea is the shell looking thing that is where you hear; Vestibular is sensory for balance)
Glossopharyngeal nerve (IX)
Sensory for taste, pharynx, palatine tonsils, tongue, middle ear
Motor for stylopharyngeus
Parasympathetic for parotid salivary glands, glands on tongue
(Pharynx and tongue; Has to do with glands and taste, throat and tongue)
Vagus nerve (X)
Jugular foramen
Sensory from pharynx, larynx, abdominal organs, taste
Motor function to soft palate, voice, tongue
Parasympathetic to thoracic and abdominal organs
Accessory nerve (XI)
Motor function for trapezius and sternocleidomastoid
Foramen magnum & Jugular foramen
(Motor neurons that move your neck)
Hypoglossal nerve (XII)
Motor function for tongue and throat
Hypoglossal canal