Anatomy Final

Front 1

Functional Areas of the Cerebral Cortex

Back 1

The three types of functional areas are:

Motor areas – control voluntary movement
 Primary (somatic) motor cortex
 Premotor cortex
 Broca’s area
 Frontal eye field

Sensory areas – conscious awareness of sensation
 Primary somatosensory cortex
 Somatosensory association cortex
 Visual and auditory areas
 Olfactory, gustatory, and vestibular cortices

Association areas – integrate diverse information
 Prefrontal cortex
 Language areas
 General (common) interpretation area
 Visceral association area

Front 2

Cerebral Cortex: Motor Areas

primary motor area

Back 2

Primary Motor Cortex
 Located in the precentral gyrus
 Pyramidal cells whose axons make up the corticospinal tracts
 Allows conscious control of precise, skilled, voluntary movements

Front 3

Cerebral Cortex: Motor Areas

premotor cortex (planning)

Back 3

Premotor Cortex
 Located anterior to the precentral gyrus
 Controls learned, repetitious, or patterned motor skills
 Coordinates simultaneous or sequential actions
 Involved in the planning of movements

Front 4

Cerebral Cortex: Motor Areas

Frontal eye field

Back 4

Frontal eye field
 Located anterior to the premotor cortex and superior to Broca’s area
 Controls voluntary eye movement

Front 5

Prefrontal Cortex

Back 5

Working memory for spatial tasks
Executive area for task management
Working memory for object recall tasks
solving complex, multitask problems


 Located in the anterior portion of the frontal lobe
 Involved with intellect, cognition, recall, and personality
 Necessary for judgment, reasoning, persistence, and conscience

Front 6

Language Areas

Cerebral Cortex: Association Areas


Back 6

Located in a large area surrounding the left (or language-dominant) lateral sulcus
 Major parts and functions:
 Wernicke’s area –sounding out unfamiliar words
 Broca’s area – speech preparation and production
 Lateral prefrontal cortex – language comprehension and word analysis
 Lateral and ventral temporal lobe – coordinate auditory and visual aspects of language

Front 7

Cerebral Cortex: Motor Areas

broca's area

Back 7

Broca’s area
 Located anterior to the inferior region of the premotor area
 Present in one hemisphere (usually the left)
 A motor speech area that directs muscles of the tongue
 Is active as one prepares to speak

Front 8

Visceral Association Area


Back 8

Located in the cortex of the insula
Involved in conscious perception of visceral sensations

Visceral - Pertaining to an internal organ of the body or the inner part of a structure.

Front 9

General (Common) Interpretation Area

Cerebral Cortex: Association Areas

Back 9

Ill-defined region including parts of the temporal, parietal, and occipital lobes
 Found in one hemisphere, usually the left
 Integrates incoming signals into a single thought
 Involved in processing spatial relationships

Front 10

Cerebral Cortex: Sensory areas

Primary somatosensory cortex

Back 10

PrImary Somatosensory Cortex
 Located in the postcentral gyrus, this area:
 Receives information from the skin and skeletal muscles
 Exhibits spatial discrimination

Front 11

Cerebral Cortex: Sensory area

somatosensory association cortex

Back 11

Somatosensory Association Cortex
 Located posterior to the primary somatosensory cortex
 Integrates sensory information
 Forms comprehensive understanding of the stimulus
 Determines size, texture, and relationship of parts

Front 12

gustatory cortex

Back 12

the gustatory cortex is the area that handles tastes. It is the brain structure that relays information about the type of taste in addition to information about a taste's intensity.

Front 13

Wernicke's area

Back 13

the region of the brain where SPOKEN language is understood
- Language Comprehension
- Semantic Processing
- Language Recognition
- Language Interpretation

Front 14

primary visual cortex

Back 14

Primary visual (striate) cortex
 Seen on the extreme posterior tip of the occipital lobe
 Most of it is buried in the calcarine sulcus
 Receives visual information from the retinas

Front 15

visual association area

Back 15

 Surrounds the primary visual cortex
 Interprets visual stimuli (e.g., color, form, and movement)

Front 16

auditory association area

Back 16

Auditory association area
 Located posterior to the primary auditory cortex
 Stores memories of sounds and permits perception of sounds
 Wernicke’s area

Front 17

primary auditory cortex

Back 17

Primary auditory cortex
 Located at the superior margin of the temporal lobe
 Receives information related to pitch, rhythm, and loudness

Front 18

Hypothalamus

Back 18

Hypothalamic Function

- Regulates blood pressure,
- rate and force of heartbeat,
- digestive tract motility,
- rate and depth of breathing
- other visceral activities
- Perception of pleasure, fear, and rage
- Maintains normal body temperature
- Regulates feelings of hunger and satiety
- Regulates sleep and the sleep cycle

Endocrine Functions of the Hypothalamus
- Releasing hormones control secretion of hormones by the anterior pituitary
- The supraoptic and paraventricular nuclei produce ADH and oxytocin


Mammillary bodies
- Small, paired nuclei bulging anteriorly from the hypothalamus
- Relay station for olfactory pathways
Infundibulum – stalk of the hypothalamus; connects to the pituitary gland
- Main visceral control center of the body

Front 19

optic chiasma

Back 19

an X-shaped structure formed by the crossing of the optic nerves in the brain. The optic nerve connects the brain to the eye.

Front 20

pituitary gland

Back 20

controls hormones and helps turn food to energy.

Front 21

mammillary body

Back 21

Mammillary bodies
 Small, paired nuclei bulging anteriorly from the hypothalamus
 Relay station for olfactory pathways

Front 22

pons

Back 22

Pons
 Relay impulses between the motor cortex and the cerebellum
 Bulging brainstem region between the midbrain and the medulla oblongata
 Forms part of the anterior wall of the fourth ventricle
 Fibers of the pons:
 Connect higher brain centers and the spinal cord
 Origin of cranial nerves V (trigeminal), VI (abducens), and VII (facial)
 Contains nuclei of the reticular formation

Front 23

medulla oblongata

Back 23

Most inferior part of the brain stem

 Cranial nerves X, XI, and XII are associated with the medulla
 Vestibular nuclear complex – synapses that mediate and maintain equilibrium
 Ascending sensory tract nuclei, including nucleus cuneatus and nucleus gracilis
 Cardiovascular control center – adjusts force and rate of heart contraction
 Respiratory centers – control rate and depth of breathing
 Additional centers – regulate vomiting, hiccuping, swallowing, coughing, and sneezing

Front 24

spinal cord

Back 24

 CNS tissue is enclosed within the vertebral column from the foramen magnum to L1
 Provides two-way communication to and from the brain
 Protected by bone, meninges, and CSF
 Epidural space – space between the vertebrae and the dural sheath (dura mater) filled with fat and a network of veins

Front 25

**corpus callosum

Back 25

Connects the left and right sides of the brain allowing communication between hemispheres. Transfers motor, sensory, and cognitive information between the brain hemispheres.

involved in several functions of the body including:
- Communication Between Brain Hemispheres
- Eye Movement
- Maintaining the Balance of Arousal and Attention
- Tactile Localization

Commissural fibers connect corresponding gray areas of the two hemispheres. These commissures allow the two hemispheres to function as a coordinated whole.

Females have a larger corpus callosum, and gender differences are seen in the language and auditory areas of the cerebral cortex

Front 26

choroid plexus

Back 26

Epithalamus
 Most dorsal portion of the diencephalon; forms roof of the third ventricle

Choroid Plexuses
 Clusters of capillaries that form tissue fluid filters, which hang from the roof of each ventricle
 Have ion pumps that allow them to alter ion concentrations of the CSF
 Help cleanse CSF by removing wastes

 Choroid plexus – a structure that secretes cerebral spinal fluid (CSF)

Front 27

thalamus(encloses third ventricle)

Back 27

Thalamic Function

controls sensory integration and motor integration. Receives sensory information and relays it to the cerebral cortex. The cerebral cortex also sends information to the thalamus which then transmits this information to other parts of the brain and the brain stem.

-Sensual afferent impulses converge and synapse in the thalamus
-Impulses of similar function are sorted out, edited, and relayed as a group
-All inputs ascending to the cerebral cortex pass through the thalamus
-Mediates sensation, motor activities, cortical arousal, learning, and memory

Front 28

pineal gland

Back 28

Epithalamus
 Most dorsal portion of the diencephalon; forms roof of the third ventricle
 Pineal gland – extends from the posterior border and secretes melatonin
 Melatonin – a hormone involved with sleep regulation, sleep-wake cycles, and mood

Front 29

corpora quadrigemina

Back 29

Front 30

cerebral aqueduct

Back 30

Midbrain structures include:
 Cerebral aqueduct aka Mesencephalon – hollow tube that connects the third and fourth ventricles

Front 31

arbor vitae

Back 31

 Arbor vitae – distinctive treelike pattern of the cerebellar white matter

Front 32

fourth ventricle

Back 32

aka Metencephalon and myelencephalon

Front 33

empty

Back 33

Front 34

cerebellum

Back 34

Cerebellar Cognitive Function
 Plays a role in language and problem solving
 Recognizes and predicts sequences of events

 Provides precise timing and appropriate patterns of skeletal muscle contraction
 Cerebellar activity occurs subconsciously


Cerebellar Processing
 Cerebellum receives impulses of the intent to initiate voluntary muscle contraction
 Proprioceptors and visual signals “inform” the cerebellum of the body’s condition
 Cerebellar cortex calculates the best way to perform a movement
 A “blueprint” of coordinated movement is sent to the cerebral motor cortex

Front 35

Meninges

Back 35

 Three connective tissue membranes lie external to the CNS – dura mater, arachnoid mater, and pia mater
 Functions of the meninges
 Cover and protect the CNS
 Protect blood vessels and enclose venous sinuses
 Contain cerebrospinal fluid (CSF)
 Form partitions within the skull

Front 36

Function of parts of the eye?

Back 36

 The sclera protects the eye and anchors extrinsic muscles
 The cornea lets light enter the eye

Vascular Tunic:
- Choroid region - Supplies blood to all eye tunics
- Ciliary Body - Anchors the suspensory ligament that holds the lens in place
- Iris - colored part that Regulates the amount of light entering the eye
--- Pupil – central opening of the iris changes due to light/mood.

Sensory Tunic: Retina
 A delicate two-layered membrane
 Pigmented layer – the outer layer that absorbs light and prevents its scattering
 Neural layer, which contains:
 Photoreceptors that transduce light energy
 Bipolar cells and ganglion cells
 Amacrine and horizontal cells
Ganglion cell axons:
 Run along the inner surface of the retina
 Leave the eye as the optic nerve
The optic disc:
 Is the site where the optic nerve leaves the eye
 Lacks photoreceptors (the blind spot)
Rods:
 Respond to dim light
 Are used for peripheral vision
Cones:
 Respond to bright light
 Have high-acuity color vision
 Are found in the macula lutea
 Are concentrated in the fovea centralis

vitreous humor in posterior(to lens) segment;
 Transmits light
 Supports the posterior surface of the lens
 Holds the neural retina firmly against the pigmented layer
 Contributes to intraocular pressure
Aqueous humor
 A plasmalike fluid that fills the anterior(to lens) segment
 Drains via the canal of Schlemm
 Supports, nourishes, and removes wastes

Lens
 A biconvex, transparent, flexible, avascular structure that Allows precise focusing of light onto the retina and Is composed of epithelium and lens fibers

Front 37

Where are different pitches processed?

Back 37

Basilar membrane

Pitch is perceived by:
 The primary auditory cortex
 Cochlear nuclei
 Loudness is perceived by:
 Varying thresholds of cochlear cells
 The number of cells stimulated

Front 38

What are the fluids of the inner ear?

Back 38

Front 39

Extrinsic eye muscle movement

Back 39

Lateral moves eye laterally,
Medial moves eye medially.
Superior elevates , turns medially
inferior depresses, turns medially

Inferior oblique - Elevates eye and turns it laterally
Superior oblique - Depresses eye and turns it laterally

Front 40

Receptors and structures for hearing?

Hearing, Static/dynamic eq.?

Back 40

MACULAE -equilibrium
Organ of Corti - hearing receptor


The Vestibule(static equilibrium/gravity)
 Suspended in its perilymph are two sacs: the saccule and utricle
 The saccule extends into the cochlea
 The utricle extends into the semicircular canals
 These sacs:
 House equilibrium RECEPTORS called maculae
 Respond to gravity and changes in the position of the head

The Semicircular Canals(Dynamic equilibrium/movement)
 Membranous semicircular ducts line each canal and communicate with the utricle
 The ampulla is the swollen end of each canal and it houses equilibrium RECEPTORS in a region called the crista ampullaris
 These receptors respond to angular movements of the head

The Cochlea(hearing)
 Coils around a bony pillar called the modiolus
 Contains the cochlear duct, which ends at the cochlear apex
 Contains the organ of Corti (hearing receptor)

Front 41

Brain Stem

Back 41

Brain Stem
 Consists of three regions – midbrain, pons, and medulla oblongata
 Controls automatic behaviors necessary for survival such as:
- heart rate
- breathing
- digesting foods
- sleeping.
It is the lowest, most primitive area of the human brain.

Front 42

Brain Lobes and function

Back 42

The FRONTAL lobe associated with reasoning, motor skills, higher level cognition, and expressive language. At the back of the frontal lobe lies the motor cortex which utilizes information from other lobes to carry out body movements. Damage to the frontal lobe can lead to changes in sexual habits, socialization, and attention as well as increased risk-taking.

The PARIETAL lobe is associated with processing tactile sensory information such as pressure, touch, and pain. The somatosensory cortex is in this lobe and is essential to the processing of the body's senses. Damage to the parietal lobe can result in problems with verbal memory, an impaired ability to control eye gaze and problems with language.

The TEMPORAL lobe isalso the location of the primary auditory cortex, which interprets sounds and the language. Contains the hippocampus which is associated with formation of memories. Damage to the temporal lobe can lead to problems with memory, speech perception, and language skills.

The occipital lobe is associated with interpreting visual stimuli and information. The primary visual cortex, which receives and interprets information from the retinas. Damage to this lobe can cause visual problems such as difficulty recognizing objects, an inability to identify colors, and trouble recognizing words.

Front 43

Seratonin

Back 43

Plays a role in sleep, appetite, nausea, migraine headaches, and regulating mood. Drugs that block
its uptake (Prozac) relieve anxiety and depression.
Activity blocked by LSD and enhanced by ecstasy (MDMA).

Mainly inhibitory Indirect action via second
messengers

Secreted by CNS: brain stem, especially midbrain; hypothalamus; limbic system; cerebellum; pineal gland; spinal cord

Front 44

Melatonin

Back 44

a sleep-inducing signal and antioxidant; and,
along with hypothalamic nuclei, helps regulate the sleep-wake cycle.

The epithalamus includes the pineal gland, which secretes the hormone melatonin.

Front 45

Dopamine

Back 45

A “feel good” neurotransmitter. Release enhanced by l-dopa and amphetamines; reuptake blocked
by cocaine. Deficient in Parkinson’s disease; dopamine neurotransmission increases in schizophrenia.

Excitatory or inhibitory depending on the receptor type

Secreted by CNS: substantia nigra of midbrain; hypothalamus; the principal neurotransmitter of
indirect motor pathways
PNS: some sympathetic ganglia

Front 46

Epinephrine

Back 46

A “feel good” neurotransmitter. Release enhanced by amphetamines; removal from synapse blocked
by tricyclic antidepressants [amitriptyline (Elavil) and others] and cocaine. Brain levels reduced by reserpine (an antihypertensive drug), leading to depression.

Excitatory or inhibitory depending on receptor type

Secreted by CNS: brain stem, particularly in the locus coeruleus of the midbrain; limbic system; some
areas of cerebral cortex
PNS: main neurotransmitter of postganglionic neurons in the sympathetic nervous system

Front 47

Parkinson’s disease

Back 47

– degeneration of the dopamine-releasing neurons of the substantia nigra

Front 48

Huntington's Disease

Back 48

Mutant huntingtin protein accumulates in brain cells and the tissue dies, leading to massive degeneration of the basal nuclei and later of the cerebral cortex.

Usually treated with drugs that BLOCK, rather than enhance, dopamine’s effects.

Front 49

cerebrovascular accidents (stroke)

Back 49

Experimental evidence indicates that glutamate, an excitatory neurotransmitter also involved in learning and memory, may be a culprit. Normally, glutamate binding to NMDA receptors opens NMDA channels that allow Ca to enter the stimulated neuron. After brain injury, neurons deprived
of oxygen begin to disintegrate, unleashing the cellular equivalent of “buckets” of glutamate.

Under these conditions, glutamate acts as an excitotoxin, literally exciting surrounding cells to death.

Front 50

Dura Mater

Back 50

 Leathery, strong meninx composed of two fibrous connective tissue layers
 The two layers separate in certain areas and form dural sinuses
Dura Mater
 Three dural septa extend inward and limit excessive movement of the brain
 Falx cerebri – fold that dips into the longitudinal fissure
 Falx cerebelli – runs along the vermis of the cerebellum
 Tentorium cerebelli – horizontal dural fold extends into the transverse fissure

Front 51

Arachnoid Mater

Back 51

 The middle meninx, which forms a loose brain covering
 It is separated from the dura mater by the subdural space
 Beneath the arachnoid is a wide subarachnoid space filled with CSF and large blood vessels
 Arachnoid villi protrude superiorly and permit CSF to be absorbed into venous blood

Front 52

Pia Mater

Back 52

Pia Mater
 Deep meninx composed of delicate connective tissue that clings tightly to the brain

Front 53

Cerebrospinal Fluid (CSF)

Back 53

 Watery solution similar in composition to blood plasma
 Contains less protein and different ion concentrations than plasma
 Forms a liquid cushion that gives buoyancy to the CNS organs

 Prevents the brain from crushing under its own weight
 Protects the CNS from blows and other trauma
 Nourishes the brain and carries chemical signals throughout it

Front 54

Blood-Brain Barrier

Back 54

 Protective mechanism that helps maintain a stable environment for the brain
 Bloodborne substances are separated from neurons by:
 Continuous endothelium of capillary walls
 Relatively thick basal lamina
 Bulbous feet of astrocytes
Blood-Brain Barrier: Functions
 Selective barrier that allows nutrients to pass freely
 Is ineffective against substances that can diffuse through plasma membranes
 Absent in some areas (vomiting center and the hypothalamus), allowing these areas to monitor the chemical composition of the blood
 Stress increases the ability of chemicals to pass through the blood-brain barrier

Front 55

Concussion vs Contusion

Back 55

A concussion is an alteration in brain function, usually temporary, following a blow to the head. The victim may be dizzy or lose consciousness. Although typically mild and short-lived, even a seemingly mild concussion can be damaging, and multiple concussions over time produce cumulative damage.

Contusion - More serious concussions can bruise the brain and cause permanent neurological damage. In cortical contusions, the individual may remain conscious. Severebrain stem contusions always cause coma, lasting from hours to a
lifetime because of injury to the reticular activating system.

Front 56

Hemorrhage

subdural or subarachnoid

Back 56

bleeding from ruptured vessels into those spaces.

Individuals who are initially lucid and then deteriorate neurologically are hemorrhaging intracranially.
- Blood accumulating in the skull increases intracranial pressure and compresses brain tissue.
- If the pressure forces the brain stem inferiorly through the foramen magnum, control of blood pressure, heart rate, and respiration is lost.

Intracranial hemorrhages are treated by surgically removing the hematoma

Front 57

Cerebral Edema

Back 57

SWELLING OF THE BRAIN

Another consequence of traumatic head injury is. At best, cerebral edema aggravates the injury. At worst, it can be fatal in and of itself.

Front 58

What is a stroke?
Most common causes of CVAs?
% that die?
What happens to survivors

Back 58

Cerebrovascular Accidents (Strokes)
1. Caused when blood circulation to the brain is blocked and brain tissue dies

2. Most commonly caused by blockage of a cerebral artery(clot)
 Other causes include compression of the brain by hemorrhage or edema, and atherosclerosis

3. 15 percent die shortly after the stroke.

4. Survivors:
- typically paralyzed on one side of the body.
- Sensory deficits or difficulty understanding or vocalizing speech.
- Some recover part of their lost faculties, because undamaged neurons sprout new branches
that spread into the injured area and take over some lost functions.

Front 59

What does an EEG measure?

Back 59

An electroencephalogram (EEG) records continuous electrical activity of brain function

Front 60

Types of Brain Waves


Back 60

- Alpha waves (8–13 Hz)– (awake but relaxed) regular and rhythmic, low-amplitude, slow, synchronous waves indicating an “idling” brain
- Beta waves(14–30 Hz) – (awake, alert) rhythmic, more irregular waves occurring during the awake and mentally alert state(concentrating)
- Theta waves(4–7 Hz) – more irregular than alpha waves; common in children,uncommon in awake adults but may appear when concentrating.
- Delta waves(4 Hz or less) – high-amplitude waves seen in deep sleep and when reticular activating system is damped. In awake adults, they indicate brain damage

Front 61

Low vs High amplitude

Back 61

Alpha waves = low = awake/relaxed
Delta waves = high = sleep

The amplitude of brain waves reflects the synchronous activity of many neurons and not the degree of electrical activity of individual neurons

Front 62

What changes brain waves?

Back 62

- Change with age, sensory stimuli, brain disease, and the chemical state of the body

- EEGs used to diagnose and localize brain lesions, tumors, infarcts, infections, abscesses, and epileptic lesions
- A flat EEG (no electrical activity) is clinical evidence of death

Front 63

Clinical consciousness

Back 63

 Clinical consciousness is defined on a continuum that grades levels of behavior:
(1) alertness,
(2) drowsiness or lethargy (which proceeds to
sleep),
(3) stupor, and
(4) coma
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 Encompasses perception of sensation, voluntary initiation and control of movement, and capabilities associated with higher mental processing
 Involves simultaneous activity of large areas of the cerebral cortex
 Is superimposed on other types of neural activity

Front 64

Conscious vs Unconscious

Back 64

Conscious = aware
Unconscious = not aware

Sleep is defined as a state of partial unconsciousness from which a person can be aroused by stimulation.

Front 65

What is fainting?
What is a coma?

Back 65

A brief loss of consciousness is called fainting or syncope. Most often, syncope indicates inadequate cerebral blood flow due to low blood pressure, as might follow hemorrhage or sudden emotional
stress.

Significant unresponsiveness to sensory stimuli for an extended period is called coma. Coma is not deep sleep. During sleep, the brain remains active and oxygen consumption resembles that of the waking state. In coma patients, oxygen use is always below normal resting levels.

Factors that can induce coma include: (1) blows to the head that cause widespread cerebral or brain stem trauma, (2) tumorsor infections that invade the brain stem, (3) metabolic disturbances such as hypoglycemia (abnormally low blood sugar levels), (4) drug overdose, (5) liver or kidney failure.

Front 66

Two major types of sleep?

Back 66

NREM stages (first 30-45 min of sleep):
 Stage 1 – eyes are closed and relaxation begins; the EEG shows alpha waves; one can be easily aroused
 Stage 2 – EEG pattern is irregular with sleep spindles (high-voltage wave bursts); arousal is more difficult
 Stage 3 – sleep deepens; theta and delta waves appear; vital signs decline; dreaming is common
 Stage 4 – EEG pattern is dominated by delta waves; skeletal muscles are relaxed; arousal is difficult

Characteristics of REM sleep:
- occurs after the fourth NREM stage has been achieved
 EEG pattern reverts through the NREM stages to the stage 1 pattern
 Vital signs increase
 Skeletal muscles (except ocular muscles) are inhibited
 Most dreaming takes place

Front 67

During sleep:
- When do you have nightmares?
- Dreams?
- When does the digestive system increase its functions?
- Sleepwalking?

Back 67

1. Most nightmares and night terrors occur during NREM stages 3 and 4

2. Most dreaming occurs during REM sleep.

3.???????????????????????????

4. NREM stage 4

Front 68

In your life, how long do you spend sleeping?
Who spends the most time sleeping?(newborns, adults, elderly)

Back 68

1. 1/3???

2. Newborns(16hrs) Adults(7.5-8.5hrs) elderly(less)

Front 69

Why is sleep important?

Back 69

Importance of Sleep
 Slow-wave sleep is presumed to be the restorative stage
 Those deprived of REM sleep become moody and depressed
 "We dream to forget." REM sleep may be a reverse learning process where superfluous information is purged from the brain
 Daily sleep requirements decline with age

Front 70

What is Narcolepsy?
Insomnia?
Sleep Apnea?

Back 70

Sleep Disorders
 Narcolepsy – lapsing abruptly into sleep from the awake state
 Insomnia – chronic inability to obtain the amount or quality of sleep needed
 Sleep apnea – temporary cessation of breathing during sleep
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Cells in the hypothalamus that secrete peptides called orexins (a wake-up chemical; also called hypocretins) are selectively destroyed in patients with narcolepsy.

True insomnia often reflects normal age-related changes, but perhaps the most common cause is psychological disturbance.

Obstructive sleep apnea occurs when loss of muscle tone during sleep allows excess fatty tissue or other structural abnormalities to block the upper airway. It is associated with obesity and made worse by alcohol and other depressants.

Front 71

What are the 2 types of memory?

Back 71

Fact (declarative) memory:
- Entails learning explicit information
- Is related to our conscious thoughts and our language ability
- Is stored with the context in which it was learned
Skill Memory

Skill memory is less conscious than fact memory and involves motor activity
- It is acquired through practice
- Skill memories do not retain the context in which they were learned
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Fact memory involves the following brain areas:
 Hippocampus and the amygdala, both limbic system structures
 Specific areas of the thalamus and hypothalamus of the diencephalon
 Ventromedial prefrontal cortex and the basal forebrain

Skill memory involves:
 Corpus striatum – mediates the automatic connections between a stimulus and a motor response
 Portion of the brain receiving the stimulus
 Premotor and motor cortex

Front 72

What affects memory acquisition?
(memory consolidation?)

Back 72

■ Emotional state. We learn best when we are alert, motivated, surprised, and aroused. Norepinephrine, a neurotransmitter involved in memory processing of emotionally charged events, is released when we are excited/stressed.
■ Rehearsal. Rehearsing or repeating the material enhances memory.
■ Association. Tying “new” information to “old” information already stored in LTM
■ Automatic memory. Not all impressions that become part of LTM are consciously formed. A student concentrating on a lecturer’s speech may record an automatic memory of the pattern of the lecturer’s tie.

NMDA receptors (calcium channels), activated by depolarization and glutamate binding, play a major role in long-term potentiation (LTP). The calcium influx that follows NMDA receptor activation mobilizes enzymes that mediate events necessary for memory formation.

Ach for declarative
Dopamine for procedural

Front 73

3 ways PNS receptors are classified

Back 73

1. STIMULUS TYPE:
 Mechanoreceptors – respond to touch, pressure, vibration, stretch, and itch
 Thermoreceptors – sensitive to changes in temperature
 Photoreceptors – respond to light energy (e.g., retina)
 Chemoreceptors – respond to chemicals (e.g., smell, taste, changes in blood chemistry)
 Nociceptors – sensitive to pain-causing stimuli

2. LOCATION:
Exteroceptors
- Respond to stimuli arising outside the body
- Found near the body surface
- Sensitive to touch, pressure, pain, and temperature
- Include the special sense organs
Interoceptors
- Respond to stimuli arising within the body
- Found in internal viscera and blood vessels
- Sensitive to chemical changes, stretch, and temperature changes
Proprioceptors
- Respond to degree of stretch of the organs they occupy
- Found in skeletal muscles, tendons, joints, ligaments, and connective tissue coverings of bones and muscles
- Constantly “advise” the brain of one’s movements
Receptor Classification by Structural Complexity

3. STRUCTURE:
Complex receptors are special sense organs
Most receptors are simple and include:
- encapsulated
-- Meissner’s corpuscles (tactile corpuscles)
-- Pacinian corpuscles (lamellated corpuscles)
-- Muscle spindles, Golgi tendon organs, and Ruffini’s corpuscles
-- Joint kinesthetic receptors

- unencapsulated
-- Free dendritic nerve endings: Respond chiefly to temperature and pain
-- Merkel (tactile) discs
-- Hair follicle receptorS

Front 74

Corpuscles, what STIMULI they pick up.

Back 74

Structure receptors
Simple Receptors: Encapsulated

Meissner’s corpuscles (tactile corpuscles) -
L: Exteroceptors
S: Mechanoreceptors (light pressure, discriminative touch, vibration of low frequency); rapidly adapting

Pacinian corpuscles (lamellated corpuscles)
L: Exteroceptors, interoceptors, and some proprioceptors
S: Mechanoreceptors (deep pressure, stretch, vibration of high frequency); rapidly adapting

Muscle spindles, Golgi tendon organs, and Ruffini’s corpuscles
L: Exteroceptors and proprioceptors
S: Mechanoreceptors (deep pressure and stretch); slowly or nonadapting

Joint kinesthetic receptors
L: Proprioceptors
S: Mechanoreceptors and nociceptors

Front 75

Inborn vs learned reflex

Back 75

Pain reflex vs driving instinct.

An inborn (intrinsic) reflex is a rapid, predictable motor response to a stimulus. It is unlearned, unpremeditated, and involuntary, and is built into our neural anatomy.

a learned (acquired) reflex, results from practice or repetition.

Front 76

Purpose of stretching(stretch reflex?)

Back 76

The stretch reflex makes sure that the muscle stays at that length

Operation of the Muscle Spindles
 Stretching the muscles activates the muscle spindle
 There is an increased rate of action potential in Ia fibers

 Contracting the muscle reduces tension on the muscle spindle
 There is a decreased rate of action potential on Ia fibers

Front 77

Most popular clinical reflex?

Back 77

the patellar or knee-jerk reflex

a stretch reflex that helps keep your knees from buckling when you are standing upright. As your knees begin to buckle and the quadriceps lengthens, the stretch reflex causes the quadriceps to contract without your having to think about it.

Front 78

Parts of Reflex Arc?

Changes seen with aging?

Back 78

There are 5 components of a reflex arc
 Receptor – site of stimulus
 Sensory neuron – transmits the afferent impulse to the CNS
 Integration center – either monosynaptic or polysynaptic region within the CNS
 Motor neuron – conducts efferent impulses from the integration center to an effector
 Effector – muscle fiber or gland that responds to the efferent impulse

Reflexes slow with age. Physical changes in nerve fibers slow the speed of conduction. And the parts of the brain involved in motor control lose cells over time.

Front 79

Myopia
Hyperopia
Presbyopia
Astigmatism

Cause?

Back 79

1. Nearsightedness - “short vision” occurs when distant objects focus in front of the retina, rather than on it. The eye is too LONG.

2. farsightedness,“far vision” occurs when the parallel light rays from distant objects focus
behind the retina. The eye is too SHORT.

3. The lens is non accommodating, a condition known as presbyopia, literally “old person’s vision.

4. astigmatism "not a point" - Unequal curvatures in different parts of the cornea or lens leads to blurry images.

Accommodation is the process that increases the refractory power of the lens. The ciliary muscles contract, pulling the ciliary body anteriorly toward the pupil and inward, releasing tension in the ciliary zonule.

Front 80

Parts of external, middle and inner ear?

Back 80

Front 81

Pathway of nerve fibers of eye

Back 81

Visual Pathways
 Axons of retinal ganglion cells form the optic nerve
 Medial fibers of the optic nerve decussate at the optic chiasm
 Most fibers of the optic tracts continue to the lateral geniculate body of the thalamus
 Other optic tract fibers end in superior colliculi (initiating visual reflexes) and pretectal nuclei (involved with pupillary reflexes)
 Optic radiations travel from the thalamus to the visual cortex
 Some nerve fibers send tracts to the midbrain ending in the superior colliculi
 A small subset of visual fibers contain melanopsin (circadian pigment) which:
 Mediates papillary light reflexes
 Sets daily biorhythms

Front 82

Pathway of sound

Back 82

1 Sound waves vibrate the tympanic membrane.
2 Auditory ossicles vibrate. Pressure is amplied.
3 Pressure waves created by the stapes pushing on the oval window move through uid in the scala
vestibuli.
4a Sounds with frequencies below hearing travel through the helicotrema and do not excite hair
cells.
4b Sounds in the hearing range go through the cochlear duct, vibrating the basilar membrane and
deecting hairs on inner hair cells.

Front 83

Pathway of nerve fibers of ear

Back 83

Auditory Pathway to the Brain
 Impulses from the cochlea pass via the spiral ganglion to the cochlear nuclei
 From there, impulses are sent to the:
 Superior olivary nucleus
 Inferior colliculus (auditory reflex center)
 From there, impulses pass to the auditory cortex
 Auditory pathways decussate so that both cortices receive input from both ears

Front 84

Rhodospin

Back 84

Rhodopsin is a biological pigment in photoreceptor cells of the retina that is responsible for the first events in the perception of light. Rhodopsins are extremely sensitive to light, enabling vision in low-light conditions.

Exposed to light, the pigment immediately photobleaches, and it takes about 45 minutes to regenerate fully in humans.

Front 85

Dark adaptation?

Back 85

Adaptation
 Adaptation to bright light (going from dark to light) involves:
 Dramatic decreases in retinal sensitivity – rod function is lost
 Switching from the rod to the cone system – visual acuity is gained
 Adaptation to dark is the reverse
 Cones stop functioning in low light
 Rhodopsin accumulates in the dark and retinal sensitivity is restored

Front 86

Where is sound processed?

Back 86

Auditory Processing
 Pitch is perceived by:
 The primary auditory cortex
 Cochlear nuclei
 Loudness is perceived by:
 Varying thresholds of cochlear cells
 The number of cells stimulated
 Localization is perceived by superior olivary nuclei that determine sound

Front 87

Where is vision processed

Back 87

visual processing extends well forward into the temporal, parietal, and frontal lobes via two parallel streams:
■ The “what” processing stream extends through the ventral part of the temporal lobe

■ The “where” processing stream takes a dorsal path through the parietal cortex all the way to the postcentral gyrus and uses information from the primary visual cortex to assess the location of objects in space. Output from both these regions then passes to the frontal cortex, which uses that information to direct activities that, among other things, can guide movements such as reaching for
a juicy peach.

Front 88

Balance and Orientation nerve Pathways

Back 88

 There are three modes of input for balance and orientation
 Vestibular receptors
 Visual receptors
 Somatic receptors
 These receptors allow our body to respond reflexively

Front 89

What substances can we taste/smell?

Back 89

Olfactory neurons are excited by volatile chemicals that bind to receptors in the olfactory cilia

Taste:
- Umani
- bitter, sweet etc.
Their chemoreceptors respond to chemicals in aqueous solution
 Taste – to substances dissolved in saliva
 Smell – to substances dissolved in fluids of the nasal membranes

Front 90

Where on the tongue are tastes processed?

Back 90

Front 91

Night Blindness

Causes/symptoms?

Back 91

poor vision at night or in dimly lit environments. Although the term “night blindness” implies that you cannot see at night, this is not the case


nearsightedness: blurred vision when looking at faraway objects
cataracts: a clouding of the eye’s lens
retinitis pigmentosa: when dark pigment collects in your retina, creating tunnel vision
Usher syndrome: a genetic condition that affects both hearing and vision

Front 92

Color Blindness

Causes/symptoms?

Back 92

the difficulty or inability to distinguish colors caused by problems with the color-sensing pigments in the eye. The majority of people who are colorblind cannot distinguish between red and green. Distinguishing yellows and blues may also be problematic. If you are completely colorblind (achromatopsia), you see only in gray or black and white.

Front 93

Detached Retina

Causes/symptoms?

Back 93

Retinal detachment will cause a sudden defect in vision.
- darkness
- In extremes, only a small hole of vision remains
- If slight, a blind spot
- floaters, little dark spots that float across the eye
- flashes of light.

serious eye disorder in which the retina separates from the underlying tissue layers.

Scarring or shrinkage of the vitreous (substance comprising the insides of the eye) can pull the retina inward.
Small tears in the retina allow liquid to seep behind the retina and push it forward.
Injury to the eye can loosen the retina. Trauma is the most common cause of retinal detachment in children, although it is comparatively unusual in the adult population.
Bleeding behind the retina, most often due to diabetic retinopathy or injury, can push it forward.
Retinal detachment may be spontaneous. This occurs more often in the elderly or in very nearsighted (myopic) eyes.
Cataract surgery causes retinal detachment 2% of the time.
Myopia.
Diabetes.
Congenital factors (those that people are born with).
Family history of retinal problems.
High blood pressure.
Stress.
Tumors.

Front 94

Macula Degeneration

Causes/symptoms?

Back 94

the progressive deterioration of the macula, the light-sensitive cells of the central retina, at the back of the eye. As these macular cells malfunction and die, central vision becomes gray, hazy, or distorted, and eventually is lost. Peripheral (away from the center) vision is unaffected

Front 95

Conduction Deafness

Causes/symptoms?

Back 95

hearing loss or impairment resulting from interference with the transmission of sound waves to the organ of Corti

Front 96

Glaucoma

Causes/symptoms?

Back 96

Glaucoma is a condition that causes damage to your eye's optic nerve and gets worse over time. It's often associated with a buildup of pressure inside the eye
Less common causes of glaucoma include a blunt or chemical injury to the eye, severe eye infection, blockage of blood vessels in the eye, inflammatory conditions of the eye, and occasionally eye surgery to correct another condition.

can cause blindness

Front 97

Otitis Media

Causes/symptoms?

Back 97

the middle ear (behind the eardrum) gets inflamed and fills with fluid

In older children and adults, symptoms include earache, hearing problems, fullness or pressure in the ear, fever, drainage from the ear, dizziness and loss of balance, and nausea or vomiting.

Symptoms without pain or fever can also mean that there’s fluid in the ear and should be looked into.

Front 98

Menier's Syndrome

Causes/symptoms?

Back 98

a disorder of the inner ear
Recurring episodes of vertigo. and vomiting.
Hearing loss.
Ringing in the ear (tinnitus).
Feeling of fullness in the ear

Causes:

Improper fluid drainage, perhaps because of a blockage or anatomic abnormality
Abnormal immune response
Allergies
Viral infection
Genetic predisposition
Head trauma
Migraines

Front 99

Neurosensory deafness

Causes/symptoms?

Back 99

Causes

Although sensorineural hearing loss is considered an idiopathic (no known cause) condition, researchers believe that other factors besides age (as in presbycusis), hereditary (as in hearing loss at birth and later in life) and environmental and physical factors (as in trauma-induced problems, tumors, noise damage and drug-induced hearing loss) may play a role in hearing loss. These factors include:

Viral infections such as influenza, rubeola, rubella, mumps, herpes simplex and CMV.
Vascular diseases such as leukemia and sickle cell anemia
Autoimmune diseases such as lupus and temporal arteritis
Symptoms

In babies with congenital deafness, failure to respond to sounds
In babies with congenital deafness, no baby babbling or other baby noises
Sounds heard are quieter, distorted and less clear
High tones are less audible
The sounds "s", "f", and "z" are not heard
Speech may be difficult to understand if there is background noise
Tinnitus
Vertigo (dizziness and loss of balance)