Lecture 3 Exam Flashcards
What are the 3 functions of cerebrospinal fluid in brain ventricles?
- buoyancy
- protection
- environment stability
How many brain ventricles are there?
4
Where are the 2 lateral ventricles located?
Above eyeball, one in each hemisphere
Where is the 3rd brain ventricle located?
In diencephalon
Where is the 4th brain ventricle located?
Between pons and cerebellum
Where in the ventricles is CSF produced?
by the choroid plexus
What is a sulcus? What are the 2 sulci in the brain?
Groove
1. central sulcus
2. Lateral sulcus
What is the left hemisphere of the brain responsible for?
Speech, writing, language, mathematics (analytic)
What is the right hemisphere of the brain responsible for?
Touch and spatial visualization (artistic side)
What are gyri (gyrus)? What are the 2 gyri of the brain?
Bumps on the brain.
1. Precentral gyrus
2. Postcentral gyrus
What does the central sulcus divide?
Divides front and back of brain
What does the lateral sulcus divide?
Divides temporal and frontal lobes
What is the longitudinal fissure?
Separates right and left sides of the brain
Where is the primary motor cortex located?
Precentral gyrus
Where is the precentral gyrus located?
Infront of the central sulcusW
Where is the postcentral gyrus located?
Behind the central sulcus
Where is the primary somatosensory cortex located?
In the postcentral gyrus
There are 5 lobes of the brain (4 names), what are they?
- frontal lobe
- temporal lobe (X2)
- Occipital lobe
- The insula
The premotor cortex is located in the frontal lobe, where within this lobe is it located?
Directly anterior to the precentral sulcus
What is the occipital lobe associated with?
Vision
What is the temporal lobe associated with?
Processing hearing information
What is the insula associated with?
Taste and storing taste in memory
What is the name of the white tract that links the right and left hemispheres of the brain?
Commissural tracts
What are the 2 commissures in the brain?
- anterior commissure
- posterior commissure
where is the cerebral nuclei (basal nuclei) located?
Masses of grey matter within the white matter of the cerebrum
The dysfunction of what area of the brain is associated with the onset of Parkinson’s disease?
Dysfunction in the cerebral nuclei
What 4 things does the cerebral nuclei include?
- Caudate nucleus
- Amygdaloid body
- Lentiform nucleus
- Claustrum
What does the caudate nucleus of the cerebral nuclei do?
Coordinates walking
What does the amygdaloid body of the cerebral nuclei do?
Participates in emotional expression
What does the lentiform of the cerebral nuclei do?
Involved in movement and muscle tone
What does the claustrum of the cerebral nuclei do?
Involved in subconscious visual processing
What are the 3 components of the diencephalon?
- Epithalamus
- Thalamus
- Hypothalamus
What are the 2 components of the epithalamus?
- Pineal gland
- Habenular nuclei
What is the function of the pineal gland?
Secretes melatonin
What is the function of the habenular nuclei?
Signals from limbic system to midbrain
What is the function of the thalamus?
receives sensory information impulses from senses
What is the function of the hypothalamus?
Control autonomic functions, endocrine system, body temp, emotional behaviour, food and water intake, sleep-wake rhythms
Where does the infundibulum attach to from the hypothalamus?
From hypothalamus to pituitary gland; where left and right sides of hypothalamus come together
What parts of the brain does the brainstem connect?
Forebrain and cerebellum to spinal cord
What does the brainstem contain?
Autonomic centers required for survival
What are the 3 brainstem regions?
- midbrain
- pons
- medulla oblongata
Where in the brainstem is the midbrain located?
Superior portion
What is the function of the midbrain?
Processes visual, auditory and motor information
The tectal plate of the midbrain has 2 components, what are they?
- Superior colliculus
- Inferior colliculus
What is the function of the superior colliculus in the midbrain?
Process visual stimuli
What is the function of the inferior colliculus in the midbrain?
Process auditory stimuli
What are the cerebral penduncles of the midbrain?
Motor tracks located on the anterolateral surface of the midbrain
What is the substantia nigra in the midbrain?
Neurons that produce dopamine
The tegmentum is located in the midbrain, what two things are located in the tegmentum?
- Red nuclei
- Reticular formation
Where in the brainstem is the pons located?
Middle, anterior portion of brainstem
The pons contains autonomic nuclei, what is the function of this?
Help regulate breathing (pontine center)
The pons houses sensory and motor cranial nerves for…?
- Trigeminal (CN V)
- Abducens (CN VI)
- Facial (CN VII)
Where in the brainstem is the medulla oblongata located?
The inferior portion of brainstem
What cranial nerves is the medulla oblongata associated with?
VII, IX, X, XI, XII
What portions of the brainstem is the reticular formation locaed in?
all 3 regions
What are the motor functions of reticular formation?
Regulate muscle tone
What are the sensory functions of the reticular formation?
process visual, auditory, and touch stimuli
What is the function of the cerebellum?
Coordinates and fine tunes skeletal muscle movements
There are 3 cerebellar peduncles, where do each of them connect to?
Superior: midbrain -> cerebellum
Middle: pons to cerebellum
Inferior: medulla oblongata to cerebellum
What does the limbic system affect?
Memory formation through integration of past memories
What are the 6 components of the limbic system?
- Cingulate gyrus
- Parahippocampal gyrus
- Amygdaloid body
- Fornix
- Mamillary body
- Olfactory bulb and associated nerves
What many pairs of cranial nerves are there?
12 - numbered with roman numerals
What are the 3 possible fibre compositions of the 12 cranial nerves?
Motor, sensory or mixed
What is the name of CN I?
Olfactory nerve
What is the name of CN ll?
Optic nerve
What is the name of CN lll?
Oculomotor nerve
What is the name of CN IV?
Trochlear nerve
What is the name of CN V?
Trigeminal nerve
What is the name of CN VI?
Abducens nerve
What is the name of CN VII?
Facial nerves
What is the name of CN VIII?
Vestibulocochlear nerve
What is the name of CN IX?
Glossopharyngeal nerve
What is the name of CN X?
Vagus nerve
What is the name of CN XI?
Accessory or spinal accessory
What is the name of CN XII?
Hypoglossal nerve
What is the function of the olfactory nerve?
Sensory - smell
What is the function of the optic nerve?
Sensory - vision
What is the function of the oculomotor nerve?
Motor - extra-ocular and pupillae muscles
What is the function of the trochlear nerve?
Motor - controls extra-ocular muscles
What is the function of the trigeminal nerve?
Sensory - touch, temp, pain
Motor - Muscles of mastication
What is the function of the abducens nerve?
Motor - muscles of the eye
What is the function of the facial nerves?
Sensory - taste & skin around ear
Motor - muscles of facial expression; salivary glands
What is the function of the vestibulocochlear nerve?
Sensory - balance and hearing
What is the function of the glossopharyngeal nerve?
Sensory - taste
Motor: muscles that assist in swallowing
What is the function of the vagus nerve?
Sensory: sensation from tongue, throat, heart, and esophagus
Motor: throat muscles, heart and lungs, larynx, trachea, most abdominal organs
What is the function of the spinal accessory nerves?
Motor control the SCM, trapezius and some pharynx muscles
What is the function of the hypoglossal nerve?
Motor, controls tongue muscles
What is the pathway of the olfactory nerve?
Cribriform plate of ethmoid bone
What is the pathway of the optic nerve?
Optic canal of sphenoid
What is the pathway of the oculomotor nerve?
superior orbital fissure of sphenoid
What is the origin of the oculomotor nerve?
anterior midbrain
What is the pathway of the trochlear nerve?
superior orbital fissure of sphenoid
What is the origin of the trochlear nerve?
posterior midbrain
What is the origin of the trigeminal nerve?
Pons
What is the origin of the abducens nerve?
Pons
What is the pathway of the abducens nerve?
Superior orbital fissure
What is the origin of the facial nerves?
Pons
What is the pathway of the facial nerves?
Internal acoustic meatus to facial canal; styloidmastoid foramen
What is the pathway of the vestibulococholear nerve?
Internal acoustic meatus
What is the origin of the glossopharyngeal nerve?
Medulla oblongata
What is the pathway of the glossopharyngeal nerve?
Jugular foramen
What is the origin of the vagus nerve?
Medulla oblongata
What is the pathway of the vagus nerve?
Jugular foramen
What is the origin of the spinal accessory nerve?
Medulla oblongata
What is the pathway of the spinal accessory nerves?
jugular foramen
What is the origin of the hypoglossal nerve?
Medulla oblongata
What is the pathway of the hypoglossal nerve?
hypoglossal canal
What is the mnemonic device for the names of the cranial nerves?
oh, oh, oh, to touch and feel very good velvet, ah heaven
What is the pneumonic for the functions of the cranial nerves?
Some say money matter, but my brother says big brains matter most
What does the SNS work on?
Works on consciously perceived or controlled processes
What is the somatic sensory system responsible for?
Vision, hearing, touch, proprioception
What is the somatic motor system responsible for?
control of skeletal muscles
What is the function of the autonomic system?
Motor system, regulates processes below conscious level to maintain homeostasis
What 3 places does the autonomic nervous system send impulses to?
- Cardiac muscles
- Smooth muscles
- Glands
What is the parasympathetic division of the ANS responsible for?
rest and digest; conserves energy and replenish nutrient stores
What is the sympathetic division of the ANS?
fight or flight; make nutrients available for use
Describe the 2 neuron pathway for motor innervation of the ANS?
- Neuronal convergence
- Neuronal divergence
What is neuronal convergence?
Numerous preganglionic axons synapse on single ganglionic cell
What is neuronal divergence?
Axons from one preganglionic cell synapse onto numerous ganglionic cells
What are myelinated fibres?
Single schwanna cell wrapped around axon segment
What is the function of the schwann cell?
Allows for neural transmission (salutatory conduction)
What are unmyelinated fibers?
single schwann cell wrapped around. multiple axons within superficial grooves
Can unmyelinated fibres perform neural transmission (salutatory conduction)?
No
In the ANS division, what are the axon lengths of the parasympathetic nerves (preganglionic and postganglionic)?
Pre: Long axons
Post: short axons
In the ANS division, what are the axon lengths of the sympathetic nerves (preganglionic & postganglionic)?
Pre: Short
Post: long
Describe the number of preganglionic axon branches (parasympathetic & sympathetic).
Parasympathetic: few branches
SYmpathetic: many branches
Describe the location of the ganglia in parasympathetic ganglia?
In or close to the effector
Describe the location of ganglia in sympathetic ganglia.
Near spinal cord
In the parasympathetic nervous system, where are preganglionic neurons housed?
- Nuclei in brainstem
- Lateral gray regions of S2-S4 spinal cord segments
What are the 4 cranial nerves that carry parasympathetic fibers?
- CNIII
- CNVII
- CNIX
- CNX
Where does CN III go to?
Intrinsic eye muscles, pupil, lens
Where does CN VII go to?
tear glands and salivary glands
Where does CN IX go to?
Parotid salivary glands
Where does the CN X go to?
To visceral organs of the thoracic and abdominal cavities
What are the 3 pelvic splanchnic nerves that exit from the sacrum?
S2, S3, S4
Describe the location of sympathetic ganglia?
- on either side of vertebral column
- Anterior to the abdominal aorta