Test 3 Flashcards
UMN
Motor neuron in CNS
LMN
Motor neuron in PNS
Are the motor pathways away from the brain ascending or descending?
Descending
What is the corticosponal pathway?
Through pyramids, crosses to the other side of the body, consists of 2 neurons UMN and then the LMN which goes to the effector muscle
What kind of pathway is involved in posture?
Ipsilateral polysnaptic pathway
Describe the sensory pathways to the brain
Ascending and crosses to the other side of the pyramid
cranial nerve 12. Arises from? Exits from? Function?
Hypoglossal Nerve
Arises from brain stem
Exits Hypoglossal canal
Mixed nerve. Motor to tongue. Sensory for muscle sense of tongue
Cranial nerve 1 Arises from? Exits from? Function?
Arises from cerebrum
Exits though olfactory foramina
SMELL
Cranial nerve II Arises from? Exits from? Function?
Arises from diencephalon
Exits optic foramen
Vision
CN III Arises from? Exits from? Function?
Arises from brain stem
Exits through superior orbital fissure
Mixed nerve (m: intrinsic to extrinsic eye muscles, s: muscle sense)
CN IV: Arises from? Exits from? Function?
Trochlear nerve
Arises from brain stem
Exits superior orbital fissure
Mixed nerve (m: ex eye muscle s: muscle sense)
CN V: Arises from? Exits from? Function?
Trigeminal Nerve Arises from brain stem 1. Ophthalmic branch out SUF 2. Maxillary branch out rotundum 3. Mandibular branch out ovale
Mixed nerve (m: chewing s: muscle sense and parts of the face)
CN VI: Arises from? Exits from? Function?
Arises from brain stem
Exits SUF
Mixed nerve (m: ex eye muscle s: muscle sense)
CN VII: Arises from? Exits from? Function?
Facial nerve
Arises from brain stem
exits skull through Stylomastoid foramen of temporal bone
Mixed nerve (m: facial expression s: taste and muscle sense)
CN VIII: Arises from? Exits from? Function?
Acoustic
Arises from brain stem
Exits through IAM
Function: sensory only
V: equilibrium
S: taste and muscle sense
CN IX: Arises from? Exits from? Function?
Glossopharangeal nerve
Arises from brain stem
Exits through jugular foramen
Mixed nerve (m: swallowing s: taste and muscle sense)
CN X: Arises from? Exits from? Function?
Vagus nerve
Arises from brain stem
Exits skull through jugular foramen
Mixed Nerve (m: parasympathetic nervous system s: muscle sense)
CN XI: Arises from? Exits from? Function?
Accessory nerve
Arises from CN I arises from brain stem and the spinal nerve arises from cervical spinal cord
Exits skull through jugular foramen
Motor to sternocleidomastoid
Sensory muscle sense of same area
Which cranial nerves are mixed?
All except I, II, and VIII
Describe the location and function of the cerebellum. Name the furrow that divides the cerebellum from the cerebrum?
Location is interior and posterior brain and it is control of coordination and equilibrium. The transverse fissure separates it from cerebrum
Contrast functions of the left vs right hemispheres of the brain?
Left Bain controls right hand, speech and analytical skills
Right brain controls artistic abilities, thinking in 3D and left hand
Describe the location and function of the limbic system?
Cerebrum and diencephalon
Responsible for emotions related to survival such as finding sex pleasurable that relate to survival
Describe the general function of the basal nuclei?
Smoothing out motor activity
Name the 9 main functional areas of the cerebral cortex. Describe the basic functions of each area and their general location (i.e. lobe)?
1 Motor, 2 Premotor, and 3 motor speech are all in the frontal lobe
4 General sensory, 9 taste are in the parietal
5 Hearing and 6 Olfaction are in the temporal lobe
7 Vision is in the occipital lobe
8 Association areas are responsible for intelligence and thought are throughout all lobes
Name the surface layer of gray matter of the cerebrum. Name the gray matter just deep to this?
Cerebral cortex, basal nuclei which “fine tunes” motor activity
Name the furrow that divides the cerebrum into left and right hemispheres. How are these hemispheres internally connected?
Longitudinal fissure divides the hemispheres of the brain. They are internally connected by the corpus callosum.
Name the 3 fiber tracts in the white matter of the cerebrum. Describe their general functions?
Commissural fibers (primarily the corpus callosum) go from one hemisphere to the other
Association fiber interconnect with a lobe of the cerebrum
Projection fibers are the ascending sensory pathways and the descending motor pathways
Name the 4 lobes of the cerebrum?
Temporal, frontal, parietal, and occipital
Define gyrus, convolution, sulcus and fissure as they relate to the cerebrum?
A gyrus to a convolution is the bump or fold of the cerebrum. The sulcus is a dip between convolutions and a fissure is a big dip.
Define cerebral cortex?
gray matter (outer cerebrum) of cerebrum
Name the largest portion of the human brain.
cerebrum
Name the 2 main components of the diencephalon. Describe their locations and functions?
Thalamus is superior to mesencephalon and is the main sensory relay center. All sensory information passes thought here besides smell. Info gets passed to the cerebrum, but also stops unimportant sensory information
Hypothalamus is just below the thalamus. It is the center for homeostasis information; thirst, temp, hunger, and regulates and autonomic nervous system. Also responsible hormone related emotions.
Describe the function of all of the parts of the mesencephalon?
cerebral peduncles are important centers for descending motor pathways.
Superior colliculi are responsible for visual reflexes and inferior colliculi and responsible for auditory reflexes
Describe the function of the pons.
bridges the part of the brain (es cerebellum and medulla) and also helps regulate breathing
Describe the function of the reticular formations (Reticular Activating System).
controls consciousness and sleep
Describe the functions of the medulla oblongata.
Connects brain and spinal cord. Vital functions are controlled here such as breathing, blood pressure and hear functions, houses the reticular activating system which causes you to be awake when stimulated and coordinated other reflexes such as swallowing, vomiting, etc.
Explain why the right cerebrum controls left muscular movements of the body.
At the pyramids the pathways (both motor and sensory) cross to the other side of the body
Which cranial nerves originate from the brain stem?
III-XII
Name the 3 parts of the brain stem and describe their locations.
Medulla oblongata is most inferior
Pons is just above it
Mesencephalon is above the pons
Name the 4 main parts of the brain.
Cerebrum, cerebellum, brainstem, and diencephalon
Describe the function of CSF.
Cushion, nourishment, and transport of nutrients/waste
Explain the formation of CSF, and describe its circulation.
Formed from blood in the choroid plexus which line the ventricles— especially in the lateral ventricles. It circulates as described in number 3 and then in the subarachnoid space of brain & spinal cord
Describe how these ventricles interconnect.
The lateral and 3rd ventricle connect through the inter-ventricular foramen
The third and fourth ventricles connect through the cerebral aqueduct
Name and locate the brain ventricles. (What is a ventricle?)
Ventricles are cavities in the brain
The cerebrum has the lateral ventricles
Diencephalon has the 3rd ventricle
Brainstem has the 4th ventricle