14.1-14.9 Flashcards
Expands along with the associated neural crest tissue; Brain and spinal cord develop from the ectodermal part of this
Neural tube
Prosencephalon, mesencephalon, and rhombencephalon
Primary brain vesicles
When prosencephalon and rhombencephalon divide further they make _____
Secondary brain vesicles
Develops into the cerebrum and lateral ventricles
Telencephalon
Forms the thalamus, hypothalamus, epithalamus, and third ventricle
Diencephalon
Continuous with the spinal cord and consists of the medulla onblongata, pons, and midbrain
Brain stem
Little brain; posterior to the brainstem
Cerebellum
Superior to the brain that consist of the thalamus hypothalamus and epithalamus
Diencephalon
Largest part of the brain
Cerebrum
Separates the cerebrum from the cerebellum
Tentorium cerebelli
Clear colorless liquid composed primarily of water that protects the brain and spinal cord from chemical and physical injuries
Cerebrospinal fluid (CSF)
Little cavities; shows the four CSF filled cavities within the brain
Ventricles
One in each hemisphere of the cerebrum
Lateral ventricle
Thin membrane that separates the lateral ventricles
Septum pellucidum
Lies between the brain stem and the cerebellum
Fourth ventricle
Functions of CSF
Mechanical protection, homeostatic function, circulation
Networks of blood capillaries in the walls of the ventricles
Choroid plexuses
Where fluid Passes through the midbrain into the fourth ventricle
Aqueduct of the midbrain
Fingerlike extensions of the arachnoid Mater The project into the dural venous sinuses, especially the superior Sagittal sinus
Arachnoid villi
Cluster of arachnoid villi
Arachnoid granulation
Also known as medulla, continuous with the superior part of the spinal cord; forms the inferior part of the brainstem; extends to the inferior border of the pons about 3 cm
Medulla oblongata
Formed by the large corticospinal tracts that pass from the cerebrum to the spinal cord
Pyramids
Crossing of 90% of the axons in the large motor tracts to opposite sides of the medullary pyramids
Decussation of pyramids
Regulates the right in force of the heartbeat in the diameter of blood vessels
Cardiovascular center
Adjust the basic rhythm of breathing
Medullary respiratory center
Causes vomiting, The forcible expulsion of the contents of the upper gastrointestinal tract through the mouth
Vomiting center
Promotes deglutition, swallowing of a mass of food that has moved from the oral cavity of the mouth into the pharynx
Deglutition center
Involves spasmodic contraction of breathing muscles that forcefully expel air through the nose and mouth
Sneezing
Involves a long-drawn and deep inhalation and then a strong exhalation that suddenly sends a blast of air through the upper respiratory passages
Coughing
Caused by spasmodic contractions of the diaphragm that ultimately result in the production of a sharp sound on inhalation
Hiccuping
Oval-shaped swelling lateral to each pyramid
Olive
Within the olive, which receives input from the cerebral cortex, red nucleus of the mid brain and spinal cord
Olivary nucleus
A group of nerve cells in the inferior part of the medulla oblongata in which axons of the gracile fasciculus terminate
Gracile nucleus
A group of neurons in the inferior part of the medulla oblongata in which axons of the cuneate fasciculus terminate
Cuneate nucleus
Extends through the medulla, pons, and midbrain
Medial lemniscus
Tracts of the posterior columns and the axons of the medial lemniscus
Posterior column-medial lemniscus pathway
Part of the gustatory pathway from the tongue to the brain; receives gustatory input from the taste buds of the tongue
Gustatory nucleus
Part of the auditory pathway from the inner ear to the brain; receive auditory input form the cochlea of the inner ear
Cochlear nuclei
Components of the equilibrium pathway from the inner ear to the brain receives sensory information associated with equilibrium from proprioceptors in the vestibular apparatus of the inner ear
Vestibular nuclei
Several nuclear in the medulla receives sensory input from and provide motor output to the cochlea of the inner ear. Convey impulses related to hearing
Vestibulocochlear nerves
Nuclear in the medulla relays sensory and motor impulses related to taste swallowing and salavation
Glossopharyngeal nerves
Nuclear in the medulla receives sensory impulses from and provide motor impulses to the pharynx and larynx and many thoracic and abdominal viscera
Vagus nerves
These fibers are actually part of the vagus nerves. Nuclei in the medulla are the origin for nerve impulses that controls swallowing
Accessory nerves
Nuclei in the medulla are the origin for nerve impulses that control tongue movements during speech and swallowing
Hypoglossal nerves
Consist of both nuclei and tracts, bridge that connects parts of the brain with one another
Pons
The ventral region of the pons forms a large synaptic relay station consisting of scattered gray centers
Pontine nuclei
Helps control breathing along with the medullary respiratory center
Pontine respiratory group
Four pairs of cranial nerves in pons
Trigeminal, abducens, facial, vestibulocochlear
Nuclei in the pons receives sensory impulses for somatic sensations from the head and face and provide motor impulses that govern chewing
Trigeminal nerves
Nuclei in the pons provide motor impulses that control eyeball movement
Abducens nerves
Nuclei in the pons receives sensory impulses for taste and provide motor impulses to regulate secretion of saliva and tears and contraction of muscles of facial expression
Facial nerves
Nuclei in the pons receives sensory impulses from and providing motor impulses to the vestibular apparatus; convey impulses related to balance and equilibrium
Vestibulocochlear nerves
Extends from the pons to the diencephalon and is about 2.5 cm
Midbrain
Contains paired bundles of axons in the anterior part of the midbrain; consist of axons of the corticospinal, corticobulbar, and corticopontine tracts which conducts nerve impulses from motor areas in the cerebral cortex to the spinal cord, medulla, and pons respectively
Cerebral peduncles
Posterior part of the membrane that contains for rounded elevations
Tectum
nuclei in the two superior elevations of the tectum; reflect centers for certain visual activities
Superior colliculi
Two inferior elevations of the tectum that are part of the auditory pathway, relaying impulses from the receptors for hearing in the inner ear to the brain
Inferior colliculi
Large and darkly pigmented; help control subconscious muscle activities
Substantia nigra
Help control muscular movements; look reddish due to their rich blood supply and iron containing pigment in their neuronal cell bodies
Red nuclei
Two pairs of cranial nerves in the midbrain
Trochlear and oculomotor
Nuclear in the midbrain provide motor impulses that controlled movements of eyeball, while accessory oculomotor nuclei provide motor control to the smooth muscles that regulate construction of the pupil and changes in shape of the lens
Oculomotor nerves
Nuclei in the midbrain provide motor impulses that control movement of the eyeball
Trochlear nerves
Broad region where white matter and gray matter exhibit a net like arrangement; extends from the superior portion of the spinal cord throughout the brainstem and into the inferior part of the diencephalon
Reticular formation
Ascending portion of the reticular formation that consist of sensory axons that project to the cerebral cortex both directly and through the thalamus
Reticular activating system
Occupies the inferior and posterior aspects of the cranial cavity
Cerebellum
Deep groove which helps separate the cerebellum from the cerebrum
Transverse Fissure
Supports the posterior part of the cerebrum that helps separate the cerebellum from the cerebrum
Tentorium cerebelli
Govern subconscious aspects of skeletal muscle movements
Anterior lobe and posterior lobe
On the inferior surface of the cerebellum that contributes to equilibrium and balance
Flocculondular lobe
Superficial layer of the cerebellum that consist of gray matter in a series of slender parallel folds
Cerebellar cortex
Slender parallel folds in the superficial layer of the cerebellum
Folia
Tracks of white matter in the superficial layer of the cerebellum, tree-like
Arbor vitae
Regions of gray matter that give rise to axons carrying impulses from cerebellum to other brain centers
Cerebellar nuclei
Attach the cerebellum to the brain stem
Cerebellar peduncles
Contain axons that extend from the cerebellum to the red nuclei of the midbrain into several nuclei of the thalamus
Superior cerebellar peduncles
The largest peduncles, their axons carry impulses for voluntary movements from the Pontine nuclei into the cerebellum
Middle cerebellar peduncles
Consist of axons of the cerebellar tracks that carries sensory information into the cerebellum from proprioceptor’s in the trunk and limbs; axons from the vestibular apparatus of the inner ear and from the vestibular nuclei of the medulla and pons; axons from the inferior olivary nucleus of the medulla that enter the cerebellum and regulate the activity of cerebellar neurons
Inferior cerebellar peduncles
Consist of paired oval masses of gray matter organized into nuclei with interspersed tracts and white matter; makes of 80% of the diencephalon
Thalamus
Joints the right and left halves of the thalamus in about 70% of human brains
Interthalamic adhesion
Receives input from the hypothalamus and since output to the limbic system; functions in emotions and memory
Anterior nucleus
Receive input from the limbic system in basal nuclei and send output to the cerebral cortex; function in emotions learning memory and thinking
Medial nuclei
Small part of the diencephalon located inferior to the thalamus, composed of a dozen or so nuclei in four major regions
Hypothalamus
Four major regions of the hypothalamus
Mammillary, tuberal, Supraoptic, preoptic
Functions of the hypothalamus
Control of the ANS, production of hormones, regulation of emotional and behavioral patterns, regulation of eating and drinking, control of body temperature, regulation of circadian rhythms and states of consciousness
Small region superior and posterior to the thalamus consist of the pineal gland and habenular nuclei
Epithalamus
Protrudes from the posterior midline of the third ventricle, part of the endocrine system because it secretes melatonin
Pineal gland
Forms the outer rim of the cerebrum
Cerebral cortex
Broad band of white matter contained axons that extend between the hemispheres
Corpus Callosum
Important note: The central sulcus separates the frontal lobe from the parietal lobe. The lateral cerebral sulcus separates the frontal lobe of the temporal load. The parieto-occipital sulcus separates the parietal lobe from the occipital lobe.
Lobes of the cerebrum
Thin sheet of gray matter situated lateral to the putamen
Claustrum
Rim of cerebral cortex on the medial surface of each hemisphere
Limbic lobe
Receives sensory information and or involved in perception
Sensory areas
Control the execution of voluntary movements
Motor areas
Deal with more complex integrative functions such as memory emotions reasoning will judgment personality traits and intelligence
Association areas
Receives nerve impulses for touch pressure vibration it’s tickle temperature pain and proprioception
Primary somatosensory area
Distorted somatic Sensory map of the body
Sensory homunculus
Receives visual information and is involved in visual perception
Primary visual area
Receives impulses for taste and is involved in gustatory perception and taste discrimination
Primary gustatory area
Receives information for sound and is involved in auditory perception
Primary auditory area
Receives impulses for smell and is involved in olfactory perception
Primary olfactory area
Each region with in the area controls voluntary contractions of specific muscles or groups of muscles with electrical stimulation
Primary motor area
Generated by neurons close to the brain surface mainly neurons in the cerebral cortex can be detected by sensors called electrodes placed on the forehead and scalp
Brain waves
