Module 12: Neurological System (Part 02) Flashcards
This is major communication link between the brain and the PNS (spinal nerves). It participates in the integration of incoming information and produces responses through reflex mechanisms
Spinal Cord
This is where the spinal cord ends.
L2
How many pairs of spinal nerves are in the spinal cord?
It gives rise to 31 pairs of spinal nerves
(1) cervical and lumbosacral enlargement give rise to the spinal nerves of the limbs
(2) Nerves from the end of the spinal cord from the cauda equina
This separates the lumbar and the sacral region (lumbosacral).
Plexus (They are separated in different types of action mechanism, movements and innervations, specially in urination) Like the Brain
This is where action potentials work so that you can urinate.
Sacral Area
Nerves from the end of the spinal cord form the ______________.
cauda equina (tail-like part of the peripheral nerves)
Explain the structure of the spinal cord
(1) Our peripheral nerves are surround to whole of our body
(2) Dorsal root goes around the back, Ventral root goes around the front
(3) Ganglion, the head of the cell body of neurons
(4) The long one is the sympathetic chain
(5) The connections in between is called the rami that bides in the sympathetic chain
Divide the spinal cord
(1) Cervical Nerves (C1 to C8) - C1 is found in the base of your neck
(2) Thoracic Nerves (T1 - T12)
(3) Lumbar Nerves (L1 - L5)
(4) Sacral Region (S1 - S5)
(5) Coccygeal Nerves and Plexus
Where is the cervical plexus found?
C1 - C4
Where is the brachial plexus found?
C5 - T1
Where is the lumbar plexus found?
L1 - L4
Where is the sacral plexus found?
L4 - S4
Where is the coccygeal plexus?
S5 - Co
These are known as the coverings of the spinal cord.
Meninges (Latin word: membranes)
What are the three (3) meningeal layers that surround the spinal cord from superficial to deep?
(1) Dura Matter
(2) Arachnoid Matter
(3) Pia matter
This is the most superficial layer. It is located between the epidural and subdural.
Dura Matter
This is located before the subarachnoid. This is also where CSF are floating, supplies nutrients, thicker than pia mater.
Arachnoid Matter
This the innermost part or meninges. This cover the spine itself.
Pia Matter
This is the space between the periosteum of the vertebral canal and the dura matter.
Epidural Space (before the dura matter)
This is the space between the arachnoid matter and the pia matter.
Subarachnoid Space (after the arachnoid)
Explain the orientation of the epidural space and the subdural space.
The epidural space is after periosteum. Subdural is the blood vessel (left); it is where the CSF leaked or bleeding if there is trauma.
(1) Subdural hematoma trauma in the subdural region because that is where most of the blood vessels are.
(2) Epidural layer is where the anesthesia is injected like when having baby in the lumbosacral area (epidural block)
This is the bony part that is located before the epidural space.
Periosteum
Explain the orientation of the arachnoid and the subarachnoid.
(1) Arachnoid (right) is the small area that has 2 linings
(2) After is subarachnoid, this is where the CSF is.
(If there is a leak of CSF (white liquid) due to trauma, there is a problem in the subarachnoid space; harder to treat than the subdural hematoma.
These are matters located in the spinal cord cross section.
The spinal cord consists of (1) peripheral white matter and (2) central gray matter
This is organized into columns (funiculi) going up, which are subdivided into tracts (fasciculi or pathways) going down, which consist of ascending and descending axons
White matter
These are the columns in the white matter that goes up (ascending).
funiculi (there are even numbers of funiculi and the Fasciculi)
These are the tracts in the white matter that goes down (descending)
Fasciculi or pathways (there are even numbers of funiculi and the Fasciculi)
Explain the descending orientation of the brain to the spinal cord.
(1) Upper part is brain
(2) Second layer is midbrain
(3) Third layer is the pons, which is a bulb
(4) Fourth layer is the medulla oblongata
(5) Last is spinal cord.
The descending blue line is delineated as the input part, where there is receptor that will receive the stimuli.
(1) We have nerve endings in all over of our body but hands have more sensation (stored memory)
(2) Stimuli goes to primary neuron that has ganglion
(3) Then to the gray matter in the SC where there
are interneurons (connection)
(4) Subsequent to that, the stimuli does goes up funiculi (in an opposite part of the body) and stops in relay station which is the midbrain
(5) Following that, stimuli is conveyed to the gray matter of the brain
(Action potentials in the brain are needed for this transport to work; electrical impulses)
(6) Messages will return back through fasciculi; going down to gray matter of SC to the Pacini corpuscles for recognition
What are the three (3) horns in the gray matter?
(1) Dorsal Horns
(2) Ventral Horns
(3) Lateral Horns
These contain sensory axons that synapse with interneurons (upper)
Dorsal Horns
These contain the neuron cell bodies of somatic motor neurons (fat area or bulb area)
Ventral Horns
These contain the neuron cell bodies of autonomic motor neurons
Lateral Horns
What does the gray and white matter commissures do?
The gray and white commissures connect each half of the spinal cord
Where do spinal nerves arise.
Spinal nerves arise from the spinal cord in numerous rootlets. The rootlets combine to form a ventral root and a dorsal root
(There is an interneuron in the gray matter and there are tracts going up to the brain)
This root contains the sensory axons of the spinal nerve.
Dorsal Root (This is where stimuli goes into towards the spinal cord) - The somatic (skeletal muscles) and autonomic (heart rate).
This root contains the motor axons of the spinal nerve.
Ventral Root (This is where the output comes from)
These are stereotypic, unconscious, involuntary responses to stimuli. It is integral to maintain homeostasis; these are highly important for survival.
Reflex
These are reflexes mediated through the somatic motor nervous system and includes responses that
(1) Remove the body from painful stimuli
(2) Keep the body from suddenly falling
(3) Cause movement because of external forces
Somatic reflexes
These are reflexes mediated through the ANS and are responsible for maintaining variables within their normal ranges of
(1) Blood pressure
(2) Blood carbon dioxide levels
(3) Water intake
Autonomic reflexes
This is the functional unit of the nervous system
Reflex Arc
These respond to stimuli and produce action potentials in sensory neurons ( it is usually your skin).
Sensory Receptors
These propagate action potentials to the CNS.
Sensory Neurons
These are in the CNS synapse with sensory neurons and with motor neurons (more about connection carry AP to the brain)
Interneurons
These carry action potentials from the CNS to effector organs (like exocrine gland such as sweat gland; endocrine glands for metabolic rate)
Motor neurons
These are the muscles or glands, respond to the action potential
Effector organs
Explain the sequence of the reflex arc.
(1) Sensory Receptors
(2) Sensory Neurons
(3) Interneurons
(4) Motor Neurons
(5) Effector Organs
Explain the Reflex Arc (does not usually reach the brain because it happens quickyly)
(1) A stimulus is detected by a sensory receptor
(2) A sensory neuron conducts action potentials through the spinal nerve and the dorsal root to the spinal cord
(3) In the spinal cord, the sensory neuron synapses with an interneuron
(4) The interneuron synapses with a motor neuron
(5) The motor axons conducts action potentials through the ventral and spinal nerve to the effector organ.
(Usually in C1-C4 (dorsal root) it is where it passes before go to the brain when we touch something; the gray matter will pick up the sensation; exchanged it to the interneuron and it return back to the hand)
What are the three (3) types of reflexes?
(1) Stretch Reflex
(2) Golgi Tendon Reflex
(3) Withdrawal Reflex
Crossed extension reflex
What pathways interact with reflexes?
Convergent and divergent pathways interact with reflexes. Reflexes are integrated within the brain and spinal cord (Higher brain centers can suppress or exaggerate reflexes)
In this type of reflex, muscle spindles detect the stretch of skeletal muscles and cause the muscle to shorten reflexively
Stretch Reflex (Knee Jerk Reflex)
Explain the stretch reflex.
(1) Muscle spindles detect the stretch of the muscle
(2) Sensory Neurons conduct action potentials to the spinal cord
(3) Sensory neurons synapse directly with motor neurons
(4) Stimulation of the motor neurons results in action potentials being conducted to the muscle causing it contract due to being stretched (the muscle that contracts is the muscle that is affected)
How is the tendon reflex test conducted?
(1) When we do examination; we use hammer and patient is sitting down and hit the area in between patella and tibia
(2) When you touch the patella (floating bone and it is not attached). If you feel the lower part of patella, it is where your patellar tendon is
(3) The lower leg will kick forward, which is the patellar reflex or the knee jerk response
(4) When you hit the tendon, there is already stretching of the muscle called the quadriceps; the green line show where the impulse go to the gray matter. One of the impulses goes up and the other goes down to the muscle to contract. When it contracts the legs will move forward (AUTOMATIC RESPONSE)
In this reflex, the Golgi tendon (tendon in the lower part behind the knee, attached to the hamstring) organs respond to increased tension within tendons and cause skeletal muscles to relax
Golgi Tendon Reflex (will relax your leg after the stretch or contraction from the stress reflex; it is a response to the increased tension in the tendon.
This is the tendon in the lower part behind the knee, attached to the hamstring
Golgi Tendon
Explain the Golgi tendon Reflex
(1) Golgi Tendon organs detect tension applied to a tendon
(2) Sensory neurons conduct action potentials to the spinal cord
(3) Sensory neurons synapse with inhibitory interneurons that synapse with motor neurons
(4) The inhibition of the motor neurons causes muscle relaxation relieving the tension applied to that tendon
This reflex pertains to the activation of pain receptors causes contraction of muscles and the removal of some part of the body from a painful stimulus
Withdrawal Reflex (from the nociceptors of the pain, the action potentials send to the nerves, and goes back to down)
Explain the withdrawal reflex.
(1) pain receptors detect painful stimulus
(2) Sensory neurons conduct action potentials to the spinal cord
(3) Sensory neurons synapse with excitatory interneurons that synapse with motor neurons
(4) Excitation of the motor neurons results in the contraction of the flexor muscles and the withdrawal of the limb from the painful stimulus
These surround the individual axons.
endoneurium
These are known as the group of axons.
Fascicles
The group of axons known as the Fascicles are bounded together by what?
perineurium
The Fascicles form the nerve and are held together by what?
Epineurium
Spinal nerves have specific cutaneous(skin) distributions called ______________.
Dermatomes (The nerves are called dermatomes. It is the sensitive it is where the area of plexus are in the body)
Summarize the 5 areas of the spine and indicate the amount of spinal nerves.
There are 5 areas
There are 31 pairs of spinal nerves
(1) Eight cervical (C1-C8) (from the skull)
(2) Twelve thoracic (T1- T12)
(3) Five lumbar (L1-L5)
(4) Five sacral (S1-S5)
(5) One coccygeal
This makes the spine flexible.
Cartilage (When you stretch intensively (hyperextension), some of the nerves in the spine can be detrimentally affected) - lfide
This is a common neurological disorder that occurs when the median nerve, which runs from your forearm into the palm of the hand, becomes pressed or squeezed at the wrist (numbing)
Carpal Tunnel Syndrome
These are formed from the branching of the spinal nerves.
Rami
These rami supply the muscles and skin near the middle of the back
Dorsal Rami
These rami in the thoracic region form intercostal nerves, which supply the thorax and upper abdomen
Ventral Rami
These join to form plexuses
(1) Cervical,
(2) Lumbar,
(3) Sacral, and
(4) Coccygeal ventral rami
These supply sympathetic nerves
Communicating Rami
What are the five (5) major plexuses?
(1) Cervical Plexus (C1 to C4)
(2) Brachial Plexus (C5 to T1)
(3) Lumbar Plexus (L1 to L4)
(4) Sacral Plexus (L4 to S4)
(5) Coccygeal Plexus (S5 to Co)
This is the major organ of the cervical plexus located in the diaphragm, where it give spaces when you breath (contraction and relaxation)
Phrenic Nerve
What forms the brachial plexus?
(1) Axillary Nerves
(2) Radial Nerves
(3) Musculocutaneous Nerves
(4) Ulnar nerves, and
(5) Median nerves
(They work together as plexus are divided to the distribution of the upper limbs. They both supply the plexuses of the upper limbs)
These are plexuses for the lower limbs
(3) Lumbar Plexus (L1 to L4)
(4) Sacral Plexus (L4 to S4)
(5) Coccygeal Plexus (S5 to Co)
(The lumbar and sacral plexuses are often considered together as the lumbosacral plexus)
These are the nerves innervated in the coccygeal plexus.
(1) Obturator (makes your left go to the left and right), femoral,
(2) Tibial Nerves, and
(3) Common fibular nerves
(4) Femoral Nerves (in the groin)
Explain the structure of the nerves arising from the plexus.
(1) Nerves arising from plexuses are distributed to skeletal muscles throughout the body
(2) Nerves arising from plexuses also supply the skin
These are nerves that cover the GI tract.
Splanchnic Nerve (They are not considered as plexus)
The Plexus is also known as what _____________.
The braid
This is contained in the cranial activity. This is the “control center” for many of the body’s functions
Brain
What are the four (4) parts of the brain?
(1) Brainstem
(2) Cerebellum
(3) Diencephalon (consists the thalamus and the hypothalamus (it is connected to the pituitary gland)
(4) Cerebrum
What are the three (3) parts of the brainstem?
(1) Midbrain
(2) Pons
(3) Medulla oblongata
(any damage in this area, you will die. This is why the first responders put a neck brace because if not respiratory and heart rate could potentially stop)
This divides the upper part and the lower part of the brain.
Corpus Callosum
This connects the spinal cord and cerebellum to the remainder of the brain. Ten of the 12 pairs of cranial nerves arise from it
Brainstem (Damage to small areas of the brainstem can cause death, whereas damage to relatively large areas of the cerebrum or cerebellum do not)
How many colliculi does the brainstem contain
four colliculi (protuberance)
This structure has more fiber that connects the midbrain to the cortex
Cerebral peduncle
This is superior to the pons and contains the corpora quadrigemina.
Midbrain
This consist of four colliculi (controls position of the head in response to visual, auditory, and somatic stimuli. They transmits auditory signal to auditory center in the cerebral cortex)
Corpora quadrigemina
This structure is responsible for the production of dopamine
Substania Nigra (In Parkinson’s disease, the black line becomes very thin because our cells degenerate and also due to the lack of dopamine. The amount of dopamine is genetically predetermined)
This structure is responsible to control the limps and help regulate body movements.
Red Nucleus (if this shrinks, the patient becomes clumsy) - This is brought about due to aging due to the decrease in circulation around the area.
These are the major descending motor pathway.
Cerebral Peduncles
This is superior to the medulla. It connects the cerebrum and the cerebellum (oblong circular shape).
Pons (Ascending and descending tracts pass through it)
This is found in the pons which is responsible for the regulating of breathing, swallowing, balance, chewing, and salivation.
Pontine Nuclei (damage to the pons can lead to ventilation-dependent medication)
This is continuous with the spinal cord and contains ascending and descending tracts
Medulla Oblongata
This anatomical structure regulates the heart, blood vessels, breathing, swallowing, vomiting, coughing, sneezing, hiccupping, balance and coordination.
Medullary Nuclei (It is near the cerebellum (proprioreception) - in charge of balance and coordination)
These are the tracts controlling voluntary muscle movement.
Pyramids
This is where the nerves travel down from the brain cross over the medulla.
Pyramid (Pyramid decussation) - control over the right and left hemisphere
Explain the cross over phenomenon in the pyramid
Pyramid in medulla oblongata is where the cross over happens. The sensation you get from the right side is passes to the left brain. If you touch something like using your left hand, it will process to the right side of the brain -CONTRALATERAL. Therefore, when the patient has a stroke in the left brain, the right side of the body will be affected.
This is located in the brainstem, which consists of nuclei scattered throughout the brainstem. It also regulates cyclic motor functions, such as breathing, walking, and chewing
Reticular Formation
This is known as the descending (downward) system, which is part of the reticular formation, maintains consciousness and regulates the sleep wake cycle.
Reticular Activating System (it maintains consciousness. The light also helps in regulating the sleep wake cycle)
What is the gray matter in the cerebellum>
It forms the cortex and the nuclei of the cerebellum.
This is also known as the arbor vitae (white matter) which means the tree of life
Cerebellum (This is highly concerned with standing up and balance; hence, people under the influence of alcohol affects the cerebellum)
What does the white matter do in the cerebellum?
(1) Connects the cerebellum to the rest of the CNS
(2) Connects the cerebellar cortex and cerebellar nuclei
What are the three (3) parts of the cerebellum?
(1) Flocculonodular lobe
(2) Vermis and the part of the lateral hemispheres
(3) Lateral hemisphere
This controls balance and eye movements, hence people with vertigo will also have a problem with maintaining balance.
Flocculonodular lobe
These control posture, locomotion, and fine motor coordination
Vermis and medial part of the lateral hemispheres
These are involved with the planning, practice, and learning of complex movements (ride bicycle, play piano, roller skating)
Lateral hemisphere
This structure of the brain is located between the brainstem and cerebrum. It is above the midbrain. The neck part.
Diencephalon
What are the four (4) parts of the diencephalon?
(1) Thalamus
(2) Subthalamus (underneath thalamus)
(3) Epithalamus (before hypothalamus)
(4) Hypothalamus (it secretes ADH which goes to collecting duct of kidney) - Without this, there is no thyroid metabolism, insulin secretion, good metabolism
This is the hormone secreted directly by the hypothalamus which travels to the collecting ducts of the kidney.
Anti-diuretic hormone (ADH)
This consists of two lobes connected by the interthalamic adhesion. This functions as an integration center.
Thalamus
The two lobes of the thalamus is connected by what?
Interthalamic Adhesion
What are the functions of the Thalamus?
(1) Functions as an integration center
(2) All sensory input that reaches the cerebrum, except for the sense of smell, synapses in the thalamus
(3) Interacts with other parts of the brain to control motor activity
(4) Involved in emotions and pain perception (limbic system)
The problems in this would affect the person’s emotions and pain perception.
Limbic System
Why is the diencephalon named as such?
Diencephalon is the embryonic face of development of the brain. It is where embryo or the first one to develop that even when you grow it is still there—A fetus can have emotions
This part of the diencephalon is inferior to the thalamus and is involved in motor function.
Subthalamus
This is superior and posterior to the thalamus and consists of the habenular nuclei and the pineal body.
Epithalamus
This part of the epithalamus is the one that influences emotions through the sense of smell.
Habenular nuclei
This part of the epithalamus may play a role in the onset of puberty and the “circadian cycle) sleep-wake cycle- produces melatonin.
Pineal Body
This is the main visceral control center of the body and is vitally important to overall body homeostasis. This is where the pituitary gland is.
Hypothalamus
What are the functions of the hypothalamus?
(1) Autonomic control center (heart rate, blood pressure, etc.)
(2) Center for emotional response/behavior
(3) Body temperature regulation
(4) Regulation of food intake - Regulation of water balance
(5) Control of endocrine system functioning
(6) Mammillary bodies are reflex centers for olfaction
This is the largest part of the brain. The cortex of this is folded into ridges called gyri and grooves called sulci or fissures
Cerebrum
These are the folded ridges of the brain.
Gyri (intelligent people have more gyri)
These are the grooves of the brain.
Sulci or fissures (The more grooves or fissure, the smarter you are)
This divides the cerebrum into left and right hemispheres
Longitudinal Fissure
What are the five (5) lobes in each hemisphere?
(1) Frontal Lobe
(2) Parietal Lobe
(3) Temporal Lobe
(4) Occipital Lobe
(5) Insula
This is a fissure and a prominent sulcus that runs down the middle of the lateral surface of the brain, separating the frontal lobe from the parietal lobe
Central Sulcus
This lobe of the brain is involved in voluntary motor function, motivation, aggression, the sense of smell, and mood
Frontal Lobe
(A person who is angry all the time, may have a shrinking of the pre-frontal lobe. This is most common with cases of dementia)
This lobe of the brain contain the major sensory areas receiving sensory input, such as touch, pain, temperature, balance, and taste (the fun site).
Parietal Lobe (This has something to do with the dream)
This lobe of the brain contain the visual centers and are important in the perception and interpretation of what we see.
Occipital Lobes
This lobe of the brain evaluate smell and hearing input and are involved in memory, abstract thought, and judgment (reasoning).
Temporal Lobe
This part of the hemisphere is located deep within the lateral fissure.
Insula Lobes
The frontal area is divided into what?
(1) Prefrontal area
(2) Premotor area
This lobe of the brain is where the auditory is (connected to the vestibule area)
Temporal Lobe
This is attached to it to the temporal are speech area, the ability of the tongue to move, talk. This is located in the anterior cerebral area.
Broca’s area (eg aphasia; cannot articulate well)
This is found the temporal lobe which is responsible to understand the thoughts.
Wernicke’s area (eg when a stroke says something different from what it is)
The coronary sulcus is divided to what
(1) Premotor cortex
(2) Pre-somatic cortex
What does the gray matter form in the cerebrum?
Gray matter forms the cortex and nuclei of the cerebrum
What does the white matter form in the cerebrum?
White matter forms the cerebral medulla, which consists of three types of tracts
What are the three (3) types of white matter or tracts in the cerebrum
(1) Association fibers
(2) Commissural Fibers
(3) Projection Fibers
The fibers crossover in the medulla oblongata. Epileptic patients have their fibers disconnected so that seizures will be smaller, so that there won’t be a connection to other side of the brain
These fibers connect areas of the cortex within the same hemisphere
Association fibers
These fibers connect the cerebral hemispheres
Commissural Fibers
These fibers connect the cerebrum to other parts of the brain and the spinal cord
Projection Fibers
This part of the cerebrum include the corpus striatum (caudate and lentiform nuclei), subthalamic nuclei, and substantia nigra (midbrain) . This anatomical structure is important in controlling motor function and has something to do with memory.
Basal Nuclei
This part of the cerebrum is involved in memory, reproduction, and nutrition. and in the emotional interpretation of sensory input and emotions in general.
Limbic System
What does the limbic system include?
Includes parts of the cerebral cortex, basal nuclei, the thalamus, the hypothalamus, and the olfactory cortex
What does the basal nuclei include?
Includes the corpus striatum (caudate and lentiform nuclei), subthalamic nuclei, and substantia nigra (midbrain)
This is the trigger - feeling pleasure, addictive drugs, food, and sex and it involves a large amount of secretion of dopamine.
Reward System - Addiction Center (the body responds when there is a reward)
What happens when there is a large amount of secreted dopamine?
(1) Dopamine helps remember the feel good experience
(2) Rush of dopamine gets smaller and smaller as behavior becomes repetitive; thus an addictive behavior is developed
(3) Large amount of released dopamine can lead to Parkinson’s disease
What parts does the reward system include?
(1) Ventral Tegmental
(2) Basal Nuclei
This is a neural system for processing fearful and threatening stimuli. It is responsible for processing strong emotions such as fear, pleasure and anger.
Amygdala
(Flight or fight reaction, process fearful and threatening stimuli)
How does the amygdala transmit signals?
It sends signals to the cerebral cortex and the thalamus to the autonomic nervous system and skeletal muscles.
What are the organs that affect the emotion of love?
(1) Amygdala
(2) Hippocampus
(3) Prefrontal cortex (it lights up when you put it in the CT scan)
(4) Oxytocin
This is the area of brain where it remembers all the addresses and names you know are store here
Hippocampus
This is known as the love hormone
Oxytocin
The brain and spinal cord are covered by what?
(1) Dura Matter
(2) Arachnoid Matter
(3) Pia Matter
This type of meninges attaches to the skull and has two layers that can separate to form Dural folds and Dural venous sinuses
Dura Matter (there is no epidural in the brain)
This space under the arachnoid matter contains CSF that helps cushion the brain – feeding and source of fluid and nutrition of the brain-
Subarachnoid Space
This type of meninges attaches directly to the brain.- it protects the cortex rea
Pia Matter
What are the protective membranes covering the brain from deep to superficial
(1) Superior sagittal sinus
(2) Bone
(3) Periosteum
(4) Aponeurosis
(5) Skin
Explain the orientation of the lateral ventricle
The lateral ventricles in the cerebrum are connected to the third ventricle in the diencephalon by the interventricular foramina (opening of the neck covers the head down to the medulla oblongata)
Explain the orientation of the third ventricle
The third ventricle is connected to the fourth ventricle in the pons by the cerebral aqueduct
This is connected to the fourth ventricle
Central Canal
Explain the orientation of the fourth ventricle
The fourth ventricle is connected to the subarachnoid space by median and lateral apertures
This is produced from the blood in the choroid plexus of each ventricle by ependymal cells
Cerebrospinal Fluid
These cells form the cerebrospinal fluid
Ependymal Cells
Explain the transport of the Cerebrospinal Fluid
(1) Moves from the lateral to the third and then to the fourth ventricle
(2) From the fourth ventricle, CSF enters the subarachnoid space through three apertures
(3) Leaves the subarachnoid space through arachnoid granulations and returns to the blood in the Dural venous sinuses.- it is recycle exchanged is happened in the dura
This is the opening of the skull to the spinal cord.
Foramen magnum
How much blood does the brain receive?
(1) High metabolic rate and brain cells cannot store high energy molecules.
(2) Only about 2% of body weight, but receives ~15%- 20% of the blood pumped by the heart
These arteries supplies blood to the brain (connected to the heart)
Carotid Arteries (Upward Stroke)
These veins returns blood to the heart (connected to the subclavian artery or the superior vena cava)
Jugular Vein (Internal and External) - when you lay down, there is an enlargement of the vein
This supplies the entire brain
Circle of Willis
Where does the most common cases of stroke happen?
Mid-cerebral artery (MCA)
What does sensation require?
(1) A stimulus
(2) A receptor
(3) Conduction of an action potential to the CNS
(4) Translation of the action potential
(5) Processing of the action potential in the CNS so that the person is aware of the sensation
This is the conscious awareness of stimuli received by sensory receptors
Sensory Perception (hearing, smell, touch and vision; sensation is where the action potentials start and is conducted by the brain)
This is the ability to perceive stimuli.
Sense
These are the means by which the brain receives information about the environment and the body
Senses
What are two basic groups of senses
(1) Somatic senses (touch, pressure, proprioception, temperature, and pain)
(2) Visceral senses (pain and pressure) – commonly involves the internal organs, which makes it hard to assess
What are the special senses?
(1) Smell
(2) Taste
(3) Sight
(4) Hearing (people can still hear even if they are unconscious or dying)
(5) Balance - proprioception. This is the ability to know our space, astrocytoma (can affect balance)
This is is formed by the endothelial cells of the capillaries in the brain. It limits what substances enter brain tissue
Blood-brain barrier
These are small superficial nerve endings and respond to light touch and superficial pressure
Merkel’s disks
These wrap around the hair follicle. This is involved in the sensation of light touch when the hair is bent (responsible for goosebumps).
Hair Follicle Receptors
These are located deep to the epidermis. They are responsible for two-point discriminative touch
Meissner Corpuscles
This is located in the dermis and is involved in continuous touch or pressure.
Ruffini End Organs
This is located in the dermis and subcutaneous tissue. These detect deep pressure and vibration. In joints, they serve a proprioceptive function
Pacini Corpuscles (vibration of the feet; diabetes do not feel vibration in the feel due to neuropathy)
What is the importance of proprioception?
(1) Provide information about the precise position of body parts.
(2) Rate of movement of various body parts
(3) Weight of an object being held in the hand.
(4) Range of movement of a joint
What are the major receptors for proprioception?
(1) Muscle spindles
(2) Golgi tendon organs
(3) Pacini corpuscles
(4) Free nerve endings
Which is in charge of the sensory areas?
Pre-frontal cortex
Which is in charge of the motor areas?
Parietal Cortex
Where is speech located?
Located only in the left cortex in most people
This area receives input from Wernicke’s area and sends impulses to the premotor and motor areas, which cause the muscle movements required for speech- MOVEMENT OF THE TONGUE ABILITY TO TALK
Broca’s area (located in the anterior portion of the prefrontal cortex)
This area comprehends and formulates speech- PEOPLE WHO CANT UNDERSTAND OR HAVE REVERSE UNDERSTADNNG
Wernicke’s area
These waves are regular and rhythmic, low amplitude, slow, synchronous waves indicating an “idling” brain.
Alpha Waves
These waves are rhythmic, more irregular waves occurring during the awake and mentally alert state.
Beta Waves
These waves are more irregular than alpha waves; common in children, but they can occur in adults experiencing frustration or who have certain brain disorders
Theta Waves
These waves are high-amplitude waves seen in deep sleep, in infancy, and in patients with severe brain disorders.
Delta Waves
What are the three (3) types of memory?
(1) Sensory Memory
(2) Short-term memory
(3) Long-term memory
When you do a CT scan on a patient with dementia, their frontal lobe sinks
This type of memory is very brief (less than a second) retention of sensory input received by the brain while something is scanned, evaluated, and acted on.
Sensory Nerves
This type of memory lasts for a few seconds to a few minutes and is limited to 7 or 8 pieces of information.
Short-term memory
This type of memory lasts for hours or longer (a lifetime)
Long Term Memory
This kind of long-term memory is responsible for the retention of facts, such as names, dates, and places
Explicit Memory
This kind of long-term memory is responsible for the development of skills such as riding a bicycle or playing a piano
Implicit memory
How many pairs of cranial nerves are there?
12
Enumerate the 12 cranial nerves
I- OLFACTORY - SMELL
II- OPTIC - VISION
III- OCCULOMOTOR - MOVEMENT OF EYES
IV- TROCHLEAR - MOVEMENT OF EYES MEDIAL
V- TRIGEMINAL - FACE- THREE NERVES
VI- ABDUCENT - MOVEMENT EYE LATERAL
VII- FACIAL - WHERE WE GET BELL’S PALSY
VIII- VESTIBULOCHOCHLEAR - HEARING
IX- GLOSSOPHARYNGEAL - POSTERIOR TONGUE 1/3
X- VAGUS - VAGAL NERVE, LARGEST
XI- ACCESSSORY - NECK
XII- HYPOGLOSSAL - ANTERIOR 2/3 OF THE TONGUE
This classification of cranial nerves includes special senses and general Senses
Sensory Nerves
This classification of cranial nerves includes somatic motor and parasympathetic
Motor Nerves
