Neurological System 2 Flashcards
Brain and the spinal cord are encased by the bones of ________; protected by the _____ (the dura mater, arachnoid, and pia mater)
the skull and vertebral column, CSF and the meninges
The brain contains over ____ neurons and _____ glial cells
12 billion, 50 billion
The brain contributes to homeostasis by _________
receiving sensory input, integrating new and stored information, making decisions, and executing responses through motor activities
Four major parts of the brain are:
brainstem, cerebellum, diencephalon, cerebrum
Posterior to the brainstem is the ______
cerebellum
Superior to the brainstem is the _____
diencephalon
Brainstem consists of _____
midbrain, pons, medulla olongata
The largest part of the brain is called _________
cerebrum
________: consists of the thalamus, hypothalamus, and epithalamus
Diencephalon
Grey matter in the brain forms the surface (consisting of _____) covers the cerebrum and cerebellum in a layer called the _____
cell bodies and interneurons, cortex
Underneath the cortex in the brain is ______
(inner) which contains ____ that connect one part of the brain to another
white matter, bundles of axons
The_______ surround and protect the brain.
cranial cavity bones and the cranial meninges
Cranial cavity bones includes:
Frontal bone, sphenoid bone, occipital bone, parietal bone
Cranial meninges have 3 layers:
Dura mater, arachnoid mater, pia mater
The cranial dura mater has ____ layers; the spinal dura mater has ___ layer
two, one
The two dural layers:
_____ layer (external)
_____ layer (internal)
periosteal, meningeal
The dural layers around the brain are fused together except the ______ that drain venous blood from the brain and deliver it into the internal jugular veins
dural venous sinuses
There is epidural space around the brain (T/F)
F
Blood vessels that enter brain tissue pass along the ____of the brain
surface
______ creates a semi-permeable membrane throughout the brain. Allows ________ (like oxygen, carbon dioxide, and water) to diffuse across into CSF. Serves to restrict what substances can pass from the bloodstream into the tissue fluid of the brain.
Blood-brain barrier, small lipid-soluble substances
Blood-brain barrier is more permeable in ________(certain location in the brain).
Choroid plexus, hypothalamus, pineal gland
______: one lateral ventricle in each hemisphere of the cerebrum
Ventricles 1 and 2
______: Superior to the hypothalamus and between the right and left halves of the
thalamus
Ventricle 3
______: lies between the pons and medulla anteriorly and the cerebellum posteriorly
Ventricle 4
The total volume of CSF is ____ mL in an adult
80 to 150
Cerebrospinal fluid (CSF) contains small amounts of ______; it also contains some ______
glucose, proteins, lactic acid, urea,
white blood cells
Functions of cerebrospinal fluid (CSF):
Buoyancy 浮力 - brain suspends in CSF, protection, chemical stability
The CSF is produced by the ____ (=membranelike) (a network of blood capillaries in walls of each ventricle) of each ____ventricle (~500mL/day)
choroid plexuses, lateral
CSF circulates in the central canal of the _______ and ______ space of the brain and spinal cord
spinal cord, in the subarachnoid
CSF is gradually reabsorbed into the blood through ____(villi), fingerlike extensions of the arachnoid mater
arachnoid granulations
Because _____of CSF are the same, the pressure of CSF normally is constant
the rates of formation and reabsorption
The _____ can be used as diagnostic parameters of brain
constituents and the flow pressure of CSF
____: has right and left hemisphere
Cerebrum
Function of cerebrum:
High mental process: thinking, reasoning, moral sense, learning, memory, personality
Initiation and control of the voluntary muscle contraction
Perception of pain, temperature, touch, special senses of light, hearing, taste and smel
Each cerebral hemisphere can be further subdivided into several lobes:
Frontal lobes
Parietal lobes
Temporal lobes
Occipital lobes
____: cannot be seen at the surface of the brain; interpret tastes and memory
The Insula
Precentral gyrus/ _____: controls voluntary muscles
Somatomotor cortex (in the motor areas)
Postcentral gyrus/ _____: receive sensory information from receptors for pain, touch, pressure, and temperature
Somatosensory cortex (in the sensory areas)
The functional asymmetry between two hemispheres is termed:
hemispheric lateralization
The ____ hemisphere is the more analytical side; it focuses on language and the types of reasoning used in math and science
left
The _____ hemisphere is more concerned with creativity and spatial ability
right
In a normal brain, the two hemispheres
communicate via ______, allowing for the smooth integration of information
the corpus callosum
Functions of somatomotor cortex:
Controls voluntary muscles, the left side controls the voluntary muscles
on the right side of the body and vice versa
Functions of somatosensory cortex:
Neurons in this region receive sensory information from the receptors for pain, touch, pressure, and temperature
The areas of the somatosensory cortex that correspond to different regions of the body are of different sizes; those areas of the body that have the largest density of touch receptors also receive the _____ motor innervation, the areas of the motor cortex that serve these
regions are correspondingly _____ than other areas
greatest, larger
Each aspect of language—including the ability to read, write, speak, and understand—is handled by a different region of the cerebral cortex.
_____: located in the left frontal lobe (for speaking)
Broca’s area
Two distinct types of sleep:
Rapid eye movement (REM) sleep, non-rapid eye movement (NREM) sleep
____: predominates in the second half of the night
Stage R
____: predominates during the first half of the night
Stage N3
_____ periods become increasingly longer toward the morning
REM
Diencephalon includes the _______
thalamus, and hypothalamus
_____: relay station for most sensory impulses that reach the primary sensory cortex of the cerebrum from the spinal cord and brainstem
Thalamus
Give two functions of hypothalamus
Control of the ANS, production of hormones, regulation of emotional and behavioural patterns, regulation of eating and drinking by a feeding centre and a thirst centre, control of body temperature, regulation of circadian rhythms
Cerebellum link up the brain with the spinal cord to facilitate the
control of __________.
balance and posture
Functions of cerebellum:
Processing sensory information, monitor body movements and send messages crucial for balance, coordination and posture
(Stores information for muscle groups to work together to perform smooth, coordinated movements
Evaluates sensory input, such as touch, spatial perception and sound)
Brainstem consists of:
Midbrain, pons, medulla oblongata
Brainstem - Midbrain has
_____ to help control subconscious muscle activities ; loss of these neurons is associated with ___
; integrate information from the ____ and ____
The substantia nigra,
Parkinson’s disease,
cerebrum, cerebellum
Brainstem - Midbrain
is associated with:
a pair of _____ nerves
a pair of ______ nerves
Oculomotor (III), Trochlear (IV)
Oculomotor (III) nerves:
Provide motor impulses that control movements of the eyeball
Provide motor control regulate constriction of the pupil and changes in shape of the lens
Trochlear (IV) nerves
Provide motor impulses that control movements of the eyeball
The pontine respiratory group is in ________
Brainstem - Pons
The pontine respiratory group together with the ____ respiratory centre helps
control _____
medullary, breathing (regulate rate and depths of respirations)
Brainstem - Pons is associated with:
a pair of ______ nerves
a pair of ______ nerves
a pair of ______ nerves
a pair of ______ nerves
Trigeminal (V)
Abducens (VI)
Facial (VII)
Vestibulocochlear (VIII)
Trigeminal (V) nerves:
Provide motor impulses that govern chewing
Abducens (VI) nerves
Provide motor impulses that control eyeball movement
Facial (VII) nerves
Receive sensory impulses for taste
Provide motor impulses to regulate secretion of saliva and tears and contraction of muscles of facial expression
Vestibulocochlear (VIII) nerves
Receive sensory impulses from and provide motor impulses to the vestibular apparatus
Related to balance and equilibrium
Which part of the brainstem control vital body functions?
Medulla oblongata
Brainstem - Medulla Oblongata associated with: _________;
contains nuclei associated with: _____
autonomous reflex activity as it houses the autonomic centers,
five pairs of cranial nerves
Cardiovascular (CV) centre:
Regulates the rate and force of the heartbeat and the diameter of blood vessels
Medulla oblongata associate with autonomous reflex activity as it houses the autonomic centers including:
Cardiovascular (CV) centre
Medullary respiratory centre
Vomiting centre
Deglutition centre
Medullary respiratory centre:
Adjusts the basic rhythm of breathing
Vomiting centre:
Causes vomiting, the forcible expulsion of the contents of the upper digestive canal through the mouth
Deglutition centre:
Promotes deglutition (swallowing) of a mass of food that has moved from the oral cavity into the pharynx (throat)
Medulla oblongata contains nuclei associated with five pairs of cranial nerves including:
Vestibulocochlear (VIII) nerves
Glossopharyngeal (IX) nerves
Vagus (X) nerves
Accessory (XI) nerves
Hypoglossal (XII) nerves
Vestibulocochlear (VIII) nerves:
Receive sensory input from and provide motor output to the cochlea of the internal ear
Glossopharyngeal (IX) nerves
Sensory and motor impulses related to taste, swallowing, and salivation
Vagus (X) nerves
Receive sensory impulses from and provide motor impulses to the pharynx and larynx and many thoracic and abdominal viscera
Accessory (XI) nerves
Part of the vagus (X) nerves
Control swallowing via the vagus nerves
Hypoglossal (XII) nerves
Control tongue movements during speech and swallowing
____: sometimes called the “emotional
brain”, the seat of emotion and
learning; links areas of the lower brainstem (which control automatic functions) with areas in the cerebral cortex associated with higher mental
functions; involved in olfaction (smell) and memory
Limbic System
Two key structures of the limbic
system are _______ and _______
Hippocampus, Amygdala
Spinal cord extends from the ___ and
descends to the ____ part of the back
brain, lumbosacral
_____ is enclosed in the vertebral column
Spinal cord
Spinal cord consists of ___ pairs of spinal nerves innervate the body,
except the head and some areas of the neck
31
Protective structures of the spinal chord includes:
vertebral column, meninges, cerebrospinal fluid
Spinal nerves travel through gaps between the vertebrae (which are held apart by intervertebral discs) and attach to the spinal cord by way of two roots: ________
the dorsal and the ventral roots
Spinal cord:
All are mixed nerves (T/F)
T
Dorsal roots
* Contain ______ fibres
* Arise from ____ neurons in the dorsal root ganglia and conduct impulses from peripheral receptors to the spinal cord
sensory (afferent), sensory
Ventral roots
* Contain _____ fibres
* Arise from ventral horn ____ neurons and extend to and innervate the skeletal muscles
motor (efferent), motor
______: may act as reflex centres – handles some automatic motor responses to sensory information by itself
Spinal cord
Meninges in the spinal cord
________:
Most superficial
Compose of dense irregular connective tissue
The outer covering of spinal and cranial nerves
Dura mater
Meninges in the spinal cord
________:
Middle
A thin, avascular covering, spider’s-web arrangement
Between the dura mater and the arachnoid mater is a thin subdural space, which contains interstitial fluid
Arachnoid mater
Subarachnoid space:
A space between the ___ and ___
Contains shock-absorbing cerebrospinal fluid
arachnoid mater, pia mater
Meninges in the spinal cord
________:
Innermost
Many blood vessels that supply oxygen and nutrients
Triangular-shaped ligaments
Pia mater
Between the bony vertebrae and the spinal dura mater is an _____ filled with a soft padding of fat and a network of veins
epidural space
A lumbar puncture is ______
A procedure removing
cerebrospinal fluid for testing at an ideal spot
A lumbar puncture takes place at ________
subarachnoid space (between the 3rd and 4th or the 4th and 5th lumbar vertebrae)
Two dorsal projections of the ____ matter are the dorsal (posterior) horns, and the ventral (anterior) horns
grey
The ________ are very short and fuse laterally to form the spinal nerves
dorsal and ventral roots
Spinal grey matter
The posterior grey horn (dorsal) contains axons of _____ and cell bodies of ______
sensory neurons, interneurons
Spinal grey matter
The anterior grey horn (ventral) contains cell bodies of ______
somatic motor neurons
Spinal grey matter
The lateral grey horn contains cell bodies of ________
autonomic motor neurons
Spinal grey matter has the following four zones:
Somatic sensory (SS)
Visceral sensory (VS)
Visceral (autonomic) motor (VM)
Somatic motor (SM)
Afferent fibres carrying impulses from peripheral sensory receptors to the ____ before they enter the spinal cord
After entering the cord, some axons of these neurons enter the ____ of the cord directly
and travel to synapse at higher cord or brain levels
Others synapse with ____ in the _____ of the spinal cord grey
matter at their entry level
dorsal root ganglion, dorsal white matter, interneurons, dorsal horns
Spinal White Matter:
Composed of myelinated and nonmyelinated nerve fibres
Allow communication between different parts of the spinal cord and between the cord and brain
These fibres run in three directions:
* _____—up to higher centres (sensory inputs)
* _____—down to the cord from the brain or within the cord to lower levels (motor outputs)
* _____—across from one side of the cord to the other (commissural fibres)
_____ and _____ tracts make up most of the white matter
Ascending, Descending, Transverse
Ascending, descending
Spinal Tracts:
______ tracts
• Consist of axons that conduct nerve impulses toward the
brain
Sensory (ascending) tracts
Spinal Tracts:
______ tracts
Consist of axons that carry nerve impulses from the brain
Motor (descending) tracts
_____ reflex
When integration takes place in the
spinal cord grey matter
The patellar reflex (knee jerk)
spinal
_____ reflex
If integration occurs in the brainstem rather than the spinal cord
Tracking movements of your eyes as you read this sentence
cranial
_____ reflex
Not consciously perceived
Involve secretion from glands or the contraction of smooth muscle (such as dilation of the pupil)
Autonomic (visceral)
_____ reflex
Involve contraction of skeletal muscles
Somatic
Reflex arc
* The ___ followed by nerve
impulses that produce a reflex
* Bypasses regions of the brain where
conscious decisions are made
pathway
Stretch/ Somatic reflexes
Involve the contraction of a ____ muscle after being stimulated by a ____ neuron
skeletal, somatic motor
Stretch/ Somatic reflexes occurs via a _____ reflex arc, by activation of a single sensory neuron that forms one synapse in the CNS with a single motor neuron
monosynaptic
_____ reflex is less sensitive than the
_____ reflex, it can override the stretch
reflex when tension is great
Tendon, stretch
Tendon reflex and somatic reflex are monosynaptic reflexes which are ______
ipsilateral
An ipsilateral reflex:
sensory nerve impulses enter the
spinal cord on the _____ from
which motor nerve impulses leave it.
same side
______ detect and respond to changes in muscle tension that are caused by passive stretch or muscular contraction
Tendon organs (Golgi tendon)(the sensory receptors lie within a tendon near its junction with a muscle)
Tendon reflex operates as a feedback mechanism to _____ by ______ before muscle force becomes so great that tendons might be torn
control muscle tension, causing muscle relaxation
Differences between reflex action and voluntary action:
Reflex action does not involve cerebrum. It is unconscious involuntary and automatic. Same stimulus induce same response. Fast. Involved spinal cord and
medulla oblongata.
Voluntary action involved cerebrum. Conscious, voluntary and automatic.
Same stimulus induce difference response. Slow. Involved cerebrum only.
Classification of receptors
By location:
_______
In skeletal muscles, tendons, joints, and ligaments and in connective tissue coverings of bones and muscles
Proprioceptors
Receptor classified by stimulus type
_______:
Respond to mechanical force such as touch, pressure (including blood pressure), vibration, and stretch
Mechanoreceptors
Receptor classified by stimulus type
_______:
Respond to chemicals in solution (molecules smelled or tasted, or changes in blood or interstitial fluid chemistry)
Chemoreceptors
Except Mechanoreceptors and Chemoreceptors,
give other 3 receptors classified by stimulus type:
Thermoreceptors, Photoreceptors, Nociceptors
Three classification of nerves:
Classified according to the direction in which they transmit impulses:
Mixed nerves - Contain both sensory and motor fibres and transmit impulses both to and from the central nervous system.
Sensory (afferent) nerves - Carry impulses only toward the CNS
Motor (efferent) nerves - Carry impulses only away from the CNS
Classify the 12 pairs of cranial nerves
Special sensory nerves: I (Olfactory), II (Optic), VIII (Vestibulocochlear)
Motor nerves: III (Oculomotor), IV (Trochlear), VI (Abducens), XI (Accessory), and XII (Hypoglossal)
Mixed nerves: V (Trigeminal), VII (Facial), IX (Glossopharyngeal), and X (Vagus)
