The Brain Flashcards
How far inferiorly does the spinal cord extend?
To the first or second lumbar vertebrae
At the end of spinal cord, it narrows to a structure. What is it called?
The Conus Medullaris
The collection of spinal nerves in the lumbar region of the spine is called?
The Cauda Equina
There are two enlargements along the length of the spine. Where are they located and why are they at that location?
They are the sites of motor and sensory neurons for the limbs located in both the cervical and lumbar regions
What is the name of the ligament that anchors the spinal cord to the first coccygeal segment?
The Filum Terminale
What is the main difference between white and grey matter?
The white matter is myelinated axons, whereas the grey matter is unmyelinated.
What types of nerve tracts run along the dorsal horn of the spinal cord?
Sensory nerve tracts
What types of nerve tracts run along the ventral horn of the spinal cord?
Motor neurons
The brainstem is divided into what three regions?
The midbrain, the pons, and the medulla oblongata
The medulla oblongata contains several centers for autonomic function. List them.
Respiratory center, Cardiac center, Vasomotor center, and reflex centers for vomiting, swallowing, coughing, and sneezing
The medulla oblongata has an important region that is responsible for the switch-over between the right and left hemispheres of the brain and the right and left portions of the body. What is this region called?
The decussation of the pyramids
What structure is contained within the medulla oblongata that contains the corticospinal tracts?
The pyramids
What cranial nerves have their nuclei within the medulla oblongata?
CN IX, X, XI, and XII
The pons has an important center in it that works closely with one in the medulla oblongata, what is it?
Respiratory centers
What cranial nerves are located in the pons?
CN V (motor), VI, VII, and part of VIII
What are the connecting tracts between the pons and the cerebrum called?
Cerebral peduncles
What region is associated with the reward center, addiction, and movement, and just so happens to produce melanin as well?
Substantia nigra
The corpora quadrigemina are masses that make up what structures?
The superior and inferior colliculi
What cranial nerve nuclei are housed within the midbrain?
CN III, IV, and V (sensory)
The cerebellum is responsible for…?
Balance/posture, learning of motions, cognitive functions and motor coordination. It does not initiate motions, but is responsible for the fine tuning of motions
Consequently, damage to the cerebellum results in what symptoms?
Lack of coordination in gait, speech, etc.
What structure connects the two hemispheres of the brain?
The corpus callosum
What are the cracks, or indentations, of the brain called?
Sulci
The ridges of the brain are called…?
Gyri
What are the four lobes of the brain?
Frontal, Parietal, Occipital, Temporal
The cerebral cortex is the site for _______ _______ and perceptive qualities of our experiences.
Sensorimotor integration
What is the division between the two hemispheres of the brain called?
The longitudinal fissure
What is the division between the temporal and frontal lobes called?
Lateral (Sylvian) sulcus
What is the division between the frontal and parietal lobes called?
The central sulcus
What are the primary functions of the frontal lobe?
Primary motor activity, behavior, and speech production
What are the primary functions of the parietal lobe?
Primary somatosensory and proprioception, association of somatosensory, vision, audition, formation of egocentric space and sense of self
What is the primary function of the occipital lobe?
Vision
What are the primary functions of the temporal lobe?
Audition, olfaction, and memory
Where is the sensory homunculus represented?
The postcentral gyrus of the parietal lobe
Where is the motor homunculus represented?
The precentral gyrus of the frontal lobe
What receives all the sensory stimuli (minus olfactory) and integrates the information to relay to specific cortical areas?
The thalamus
The walls of the hypothalamus make up which ventricle?
The 3rd ventricle
What are some primary functions of the hypothalamus?
Integration of autonomic nervous system; regulates water balance, body temp, and thirst; produces antidiuretic hormone and oxytocin
List the cranial nerves.
Helpful mnemonics:
“Oh, oh, oh, to touch and feel a guys vein and hotdog.”
-or-
“Oh, oh, oh, tiny tits are fun and give virgins awkward hips.”
CN I - Olfactory nerve CN II - Optic nerve CN III - Oculomotor nerve CN IV - Trochlear nerve CN V - Trigeminal nerve CN VI - Abducens nerve CN VII - Facial Nerve CN VIII - Vestibulocochlear nerve/Auditory nerve CN IX - Glossopharyngeal nerve CN X - Vagus nerve CN XI - Accessory nerve CN XII - Hypoglossal nerve
What are the functions of CN I, II, III and IV?
CN I (olfactory nerve) - smell CN II (optic nerve) - sight CN III (oculomotor nerve) - eye movements, pupil constriction CN IV (trochlear nerve) - superior oblique muscle
What are the functions of CN V, VI, and VII?
CN V (trigeminal nerve) - sensory to face, motor to muscles of mastication CN VI (abducens nerve) - innervation to lateral rectus muscle CN VII (facial nerve) - muscles of facial expression, taste
What are the functions of CN VIII, IX, and X?
CN VIII (Vestibulocochlear/auditory nerve) - hearing, balance CN IX (glossopharyngeal nerve) - taste, secretomotor to parotid, stylopharyngeus CN X (vagus nerve) - motor to laryngeal/pharyngeal muscles, parasympathetic to everything north of the splenic flexure
What are the functions of CN XI and XII?
CN XI (spinal accessory nerve) - sternocleidomastoid and trapezius muscles CN XII (hypoglossal nerve) - muscles of the tongue
How would you test for function of CN I and II?
Testing the olfactory nerve is done by waving a nonirritating scent under a patient’s nose and asking if they can smell it. The optic nerve is tested with the Snellen chart and fundoscopic examination.
How would you test CN III, IV, and VI?
Observing the alignment of the eyes and by having the patient follow a moving object with their eyes. Also shining a light in the eye to look for pupillary constriction to test the oculomotor nerve, specifically.
How would you test CN V?
Lightly touching the face and cornea with a cotton swab and observing bite strength
How would you test CN VII?
By observing the ability of the patient to make various facial expressions. Taste is tested by dipping a cotton swab in a flavored substance and placing it on the anterior 2/3 of the tongue.
How would you test CN VIII and IX?
The auditory nerve is tested with a tuning fork and introducing head movements while observing the eyes for nystagmus (involuntary eye movement). The glossopharyngeal nerve is tested by assessing taste on the posterior 1/3 of the tongue and determining if sensation is intact on arches of the palate.
How would you test CN X, XI, and XII?
The vagus is tested by asking the patient to speak. The accessory nerve is tested by contracting the SCM and trapezius muscles against resistance. The hypoglossal nerve is tested by asking the patient to stick their tongue out straight.
