The Brain and Autonomic Nervous System Flashcards
What is not stored in the brain and must have a constant supply?
Glucose
Brain-related symptoms are always the first of hypoglycemia (low blood sugar) what are some of the symptoms?
lightheadedness, dizziness, irritability, headache.
The brain gets its blood supply carrying glucose and oxygen from what?
The bilateral common carotid arteries and bilateral vertebral arteries.
Blood returns to the lungs from the brain via the?
bilateral internal jugular veins
What is the Blood-brain barrier?
prevents the passage of many substances from the blood into brain tissue
What is the Blood-brain barrier (BBB) Comprised mostly of? And what do they do?
astrocytes which protects the brain from many harmful substances.
What crosses the BBB quickly?
A few water-soluble substances, such as glucose lipid-soluble substances, such oxygen, carbon dioxide, alcohol, & most anesthetic agents
What crosses the BBB more slowly
Creatinine, Urea, and most ions
What doesn’t cross the BBB at all?
Some substances, such as proteins and antibiotics
How is the BBB broken down
trauma, inflammation, and certain toxins
Can all drugs pass into the BBB?
no, Certain drugs cannot pass, making it difficult to treat some diseases and infections.
What are the names of the 3 layers of connective tissue-protective covering of the brain? (The cranial meninges)
Dura mater, arachnoid mater, pia mater
What is the Dura mater? And what is it surrounded by?
the superficial layer of The cranial meninges made of dense irregular CT. epidural space.
What is the arachnoid mater?
the middle layer of the cranial meninges
What is the pia mater?
One of the cranial meninges that is the innermost layer made of a thin, transparent layer of CT that adheres to the brain and spinal cord.
What is the epidural space?
a layer of fat and connective tissue between the dura mater and the internal wall of the vertebral canal
Does the arachnoid mater have a blood supply?
No
What is the subdural space
the space between the arachnoid mater and the dura mater
Does the pia mater have any blood supply
contains many blood vessels that supply oxygen and nutrients to the brain and spinal cord
Blood vessels are sheathed by pia mater as they penetrate the brain from the surface inward
What is the subarachnoid space?
the space between the arachnoid mater and pia mater
What are the parts of the brain are separated by three extensions of the dura mater called?
Falx cerebri, Falx cerebelli, and Tentorium cerebelli
What is the Falx cerebri?
separates the left & right hemispheres of the brain
What is the Falx cerebelli?
separates the two hemispheres of the cerebellum
What is the Tentorium cerebelli?
separates the cerebrum from the cerebellum
What is Cerebrospinal Fluid (CSF)?
Clear colorless liquid that protects the CNS against harmful chemicals and physical damage. Also carries oxygen, glucose and other needed chemicals.
Where is Cerebrospinal Fluid produced
choroid plexuses found in the ventricles of the brain.
What is the Choroid Plexus?
a network of capillaries and blood vessels inside the ventricles that produce CSF.
What are Ventricles?
cavities within the brain that contain large amounts of CSF
Where is the Lateral Ventricle located?
Surrounded by the genu of the corpus callosum
Where is the Third Ventricle located?
inferior to the corpus callosum
Where is the Fourth Ventricle located?
between the pons and the cerebellum
What is the Cerebral Aqueduct?
CSF-filled channel through the midbrain of the brainstem that connects the 3rd & 4th ventricles to each other.
What is the Medulla Oblongata?
most inferior part of the brain stem. Contains the ascending sensory and descending motor tracts.
What are Pyramids
wo lateral, external bulges formed by the two largest motor tracts.
What is Decussation of the pyramids?
the pyramids cross within the medulla oblongata taking most of the motor axons with it.
What does the Medulla Oblongata contain and control?
cardiovascular center- controlling rate and force of heartbeat as well as the diameter of blood vessels.
medullary rhythmic area of the respiratory center- controlling the rhythm and rate of breathing.
reflexes such as vomiting, coughing, and sneezing.
What cranial nerves emerge from the medulla oblongata
Vestibulocochlear (CN VIII) cochlear branch
Glossopharyngeal (CN IX)
Vagus (CN X)
Accessory Nerve (CN XI)
Hypoglossal (CN XII)
What does the Vestibulocochlear (CN VIII) cochlear branch nerve control?
sensory and motor associated with hearing (cochlear branches)
What does the nerve Glossopharyngeal (CN IX) control?
sensory and motor control taste, swallowing, and salivation
What does the nerve Vagus (CN X) control?
sensory and motor associated with voice production, digestive secretions, taste, and slowing of heart rate
What does the Accessory Nerve (CN XI) nerve control?
motor swallowing and shoulder shrug (spinal portion)
What does the Hypoglossal (CN XII) nerve control?
motor tongue movement and swallowing
Where is the pons located? And what does it do?
superior to the medulla and anterior to the cerebellum
Helps control breathing with the pneumotaxic and apneustic areas.
What are the Cranial Nerves emerging from the pons?
Trigeminal (CN V),
Abducens (CN VI),
Facial (VII),
Vestibulocochlear (CN VIII) vestibular branch:
What does the Trigeminal (CN V) nerve control?
sensory and motor-sensory from the head and face, motor for chewing (mastication)
What does the Abducens (CN VI) nerve control?
motor eyeball movement
What does the Facial (VII) nerve control?
motor and sensory associated with sensory for taste and motor for saliva secretion, tears, and facial expression
What does the Vestibulocochlear (CN VIII) vestibular branch: nerve control?
sensory and motor associated with balance and equilibrium
Where is the midbrain located?
directly superior to the pons
What are the Cerebral peduncles?
the anterior part of the midbrain containing axons of the sensory and motor tracts.
What is the Tectum?
posterior part of the midbrain divided into the corpora quadrigemina
What are the two parts of the corpora quadrigemina called?
Superior Colliculi and Inferior Colliculi
What is the Superior Colliculi?
two superior elevations that are reflex centers controlling movements of the eyes, head, and neck in response to visual and other stimuli.
What is the Inferior Colliculi?
two inferior elevations that are reflex centers for movements of the head and truck in response to auditory stimuli.
What is the Cerebral Aqueduct?
CSF-filled channel between the tectum & the cerebral peduncles that connects the 3rd & 4th ventricles to each other.
What are the Cranial Nerves emerging from Midbrain?
Oculomotor (III) and
Trochlear (IV)
What does the Oculomotor (III) nerve control?
motor movements of the ipsilateral eyeball, constriction of the pupil, changes in lens shape.
What does the Trochlear (IV) nerve control?
motor movements of the ipsilateral eyeball
Where is the cerebellum located?
Posterior and inferior to the cerebrum, posterior to the occipital lobe.
What are the main structures of the cerebellum?
cerebellar hemispheres on the left and right
Vermis: the raised structure along the median lineiii
Arbor vitae: highly branched, internal white matter