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Human Physiology 1 > Lecture 12-13 Outline > Flashcards

Lecture 12-13 Outline Flashcards

1
Q

CNS develops from a…

A

hollow tube

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2
Q

At the 3rd week of development, the human brain starts as a…

A

hollow tube

  • the egg has been fertilized, it’s a ball of cells starting to organize
  • called neuralation
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3
Q

By the 4th week it (hollow tube)…

A

specializations in the anterior end

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4
Q

Human brain at ~4 weeks

A

Hollow tube with

  • forebrain
  • midbrain
  • hindbrain
  • spinal cord
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5
Q

Human brain at ~4-6 weeks

A
  • MASSIVE increase in the # of cells & they are starting to move/migrate around these new structures
  • forebrain –> cerebrum & diencephalon
  • midbrain –> midbrain
  • hindbrain –> pons & cerebellum, medulla oblongata
  • spinal cord
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6
Q

Human brain at ~11 weeks

A

all of this has really started to enlarge & start to bend & there is a massive increase in the # of cells in the cerebrum
- cerebrum expands so much that it wraps around the diencephalon

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7
Q

Pons is found _____, & cerebellum is _____

A

ventrally

dorsally

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8
Q

The medulla oblongata is the

A

transition into the rest of the spinal cord

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9
Q

What does the Sagital Section/Slice show

A

if someone cut from the nose straight through the back of the head & right down the middle so it’s bisecting the left half & right half of an adult

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10
Q

Cerebellum is called this b/c

A

it looks like a little brain

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11
Q

Early names for the brain sections

A
  • forebrain
  • midbrain
  • hindbrain
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12
Q

Late names for the brain sections

A

forebrain –> cerebrum & diencephalon

midbrain –> midbrain

hindbrain –> pons/cerebellum & medulla

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13
Q

Derivatives for the brain sections

A

Cerebrum –> cerebral hemispheres, basal ganglia, lateral & 3rd ventricles

diencephalon –> thalamus & hypothalamus

midbrain –> superior, inferior colliculi & substantia nigra

pons/cerebellum –> pons & cerebellum

medulla –> medulla (nucleus of the solitary tract)

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14
Q

What does the medulla play a huge role in?

A

in regulation of homeostasis (nucleus of the solitary tract)

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15
Q

Define Ventricles

A

fluid filled cavities within the brain, remnants of the “hollow tube” from which the brain developed

  • fact that their filled with fluid is imp. for part of the protection of the brain
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16
Q

Central Canal

A

hollow tube in the spinal cord; continuous with the ventricles

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17
Q

What are the ventricles & central canal lined by?

A

ependymal cells (glial cells)

  • ventricles & central canal are aligned by these
  • glial cells that form a water tight barrier b/t the fluid filled cavity of the ventricle & the central canal & the rest of the brain tissue
  • specialized for transport
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18
Q

How are the ependymal cells (glial cells) specialized for transport?

A
  1. allow the MOVEMENT of certain SOLUTES across

2. PROTECT the NEURAL CELLS on one side from the constituents within the CSF

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19
Q

Lateral ventricles

A

1 on each side

1st & 2nd

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20
Q

Lateral ventricles

A

1 on each side

1st & 2nd

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21
Q

Third ventricle

A

around the area of the hypothalamus

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22
Q

Fourth ventricle

A

found in the hindbrain

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23
Q

Where is the central canal formed?

A

in the spinal cord

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24
Q

Grey matter

A

UNmyelinated cell bodies, axon terminals & dendrites
- neuronal cell bodies are most often found clustered together in groups called nuclei, or on the outer surface of the brain as the cerebral cortex

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25
Q

What does nuclei imply?

A

implies that groups of neurons that do similar things are grouped together & that group of neurons is called a nucleus

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26
Q

White matter

A

myelinated axons

- kind of like wires - sending info from 1 place to the other (lot of processing being done)

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27
Q

Ganglia

A

knot of cells (often used for collections of neurons outside the CNS, but there are some within the brain & spinal cord)

  • kind of the same as nucleus (mean the same)
  • “groups of neurons”
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28
Q

What is a coronal slice?

A

sliced from one side of the head straight through the other

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29
Q

Where is there a lot of grey matter in the brain?

A

in the pons & cerebellum

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30
Q

In the BRAIN, grey matter is found ______

A

outside

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31
Q

In the BRAIN, white matter is found ______

A

inside

  • axons from neurons that have their cell bodies in the grey matter
  • myelinated axons in the white going to various places
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32
Q

What is used as support & protection for CNS?

A
  • bony skull & vertebral column
  • wrapped by 3 protective & nourishing membranes called MENINGES
  • Cerebrospinal fluid (CSF)
  • Blood-Brain barrier
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33
Q

What is the bony skull & vertebral column?

A
  • both made of bones
  • very hard structures
  • 1 of the main jobs is to form a protective layer over the CNS (b/c CNS is fragile & needs to be protected)
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34
Q

Meninges

A

3 protective & nourishing membranes that wrap the CNS to support & protect it

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35
Q

What is a CAT/CT Scan?

A
  • specialized X-ray that takes pics sequentially (so 1 after the other)
  • X-rays are digitalized & a special computer program assembles them & allows us to get an idea of the 3-D structure
  • series of images starting from back of someones head, moving to the front
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36
Q

Describe Dura Matter

A
  • “HARD mother” in Latin
  • tough, leathery layer
  • immediately inside the skull
  • helps HOLD your brain & spinal cord IN PLACE/hold still
  • also a PHYSICAL protection
  • if someone has a skull injury (fractured skull), this is helping PREVENT that object that hit their head from PENETRATING into the brain itself
  • FORMS RESERVOIRS which is important for the circulation of your brain

OUTER MEMBRANE OF THE MENINGES

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37
Q

Describe Emissary Vein

A
  • lots of veins that are draining blood that collects in the dural sinus (so blood thats been circulating in your brain), & some of that is pushed out through the skull through these these emissary veins
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38
Q

If you’ve hit your head & it causes a small cut in your scalp, it will bleed a lot more then you’ll expect. Why?

A

b/c your skull is one of the places where some of your blood vessels/veins draining your brain are actually collecting that blood & will eventually get recirculated back to the rest of your body

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39
Q

Describe Dural sinus/cavity

A
  • middle of Dura Matter
  • part of the circulatory system
  • it’s venous - so it is continuous with the veins that are draining the blood from the brain
  • a reservoir where blood is collecting after being drained from the brain itself
  • a # of small veins that exit from the Dural Sinus & will eventually go out through the skull (exit) & out through your scalp
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40
Q

Describe Pia Matter

A
  • soft & delicate
  • directly ontop of the surface of the hemispheres of the brain of the cerebrum
  • another 1 of the meningia layers
  • very tightly & closely associated with the neural tissue underneath
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41
Q

Arachnoid Membrane

A
  • called this b/c the hashes on diagram look like spider webs
  • layer in middle
  • connected to the Pia matter by very fine fibrous structures

THE MIDDLE MEMBRANE LAYER OF THE MENINGES

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42
Q

Describe Arachnoid trabeculae

A
  • bits connecting Arachnoid membrane to the Pia

- fine spider web like processes that hold the Arachnoid to the Pia

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43
Q

Describe Arachnoid Villus (villi)

A

projections from the Arachnoid membrane, into the dural sinuses & other sinuses within the dura matter that will play an imp. role in the movement of CSF

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44
Q

Getting a cut on your scalp could be dangerous if it’s deep & bleeding. Why?

A

b/c if you get an infection there it is a really good pathway for bacteria to make it into your CNS, causing a life threatening infection

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45
Q

A deep cut in the scalp can be dangerous:

A

some veins pass thru the skull (b/c you can get bacteria in there)

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46
Q

What is meningitis?

A

is a contagious bacterial, virus or fungal infection of the meninges cause swelling & pressure on the brain

  • which is bad b/c neurons don’t like to be subjected to pressure (bad implication for circulation & the way they fire APs)
  • gets bad fast
  • if untreated can end in death
  • concern in young adults (hs or uni)
  • more common in large groups of people
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47
Q

Traumatic head injury can cause:

A
  • epidural bleeding (b/t the skull & dura)
  • subdural bleeding (b/t the dura & arachnoid)
  • subarachnoid bleeding (b/t the arachnoid membrane & the pia matter)
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48
Q

What is epidural bleeding?

A

b/t the skull & dura

  • Natasha Richardson had this from skiing injury & died
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49
Q

What is Subdural bleeding?

A

b/t the dura & arachnoid

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50
Q

What is Subarachnoid bleeding?

A

b/t the arachnoid membrane & the Pia matter

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51
Q

Cerebrospinal fluid is secreted into the…

A

ventricles (lateral–>3rd–>4th) & flows throughout the subarachnoid space (& subdural space) where it cushions the CNS (b/t the brain & skull)
- stops the brain from smashing up against the side of skull where it gets tossed around (think egg in water vs egg no water in jar)

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52
Q

Choroid plexus of 3rd ventricle (also in 4th & 2nd lateral)…

A
  • secretes CSF

- within the neurons, there are specialized cells derived from the ependymal cells

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53
Q

Arachnoid villi

A

pushing through dura & into dura sinus (like a blister)

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54
Q

The CSF that is…

A

circulating around the brain is getting collected up the venous drainage of the brain & from there its going to make it back out into your blood stream

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55
Q

Why would the CSF move out through these arachnoid villi?

A

b/c it keeps the fluid in constant motion
- in that way the CSF can collect up some of the waste from the brain & bring it out & dump it into the circulation to be dealt with appropriately

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56
Q

What are the 4 steps of CSF circulation?

A
  1. Produced by CHOROID PLEXUS in the ventricles
  2. Exits brain thru (2 pores) foramen of MAGENDIE & foramen of LUSCHKA (median & lateral)
  3. Some CIRCULATES around the SPINAL CORD, some circulates INTO SUBARACHNOID SPACE
  4. Enters ARACHNOID VILLI (granulations), & crosses into VENOUS BLOOD
57
Q

Why is CSF important?

A
  1. Helps MAINTAIN proper SOLUTE CONCENTRATIONS in the interstitial fluid surrounding neurons
    ex: if there is high concen. of K+; some can get mopped up by glial cells & some make its way out into the CSF & carry away from the brain)
  2. Helps REMOVE WASTE
    ex: metabolic waste
  3. Provides a CUSHION for the brain
    - most anatomical function
    - so when your head moves around; your brain & spinal cord don’t bang into the side of your skull *neural tissue is delicate & easily damaged & so it PREVENTS IT FROM PHYSICAL DAMAGE OF BRAIN & SPINAL CORD
58
Q

Describe the blood-brain barrier

A

barrier b/t the interstitial fluid (that surrounds neurons) of the brain & the plasma

  • due to the specialized anatomy of blood vessels in the CNS
  • keeps UNwanted materials OUT, keeps WANTED materials IN (the brain)
59
Q

Describe Circulation IN THE BODY (skeletal muscle for ex)

A

Endothelial cells are NOT connected & have pores (called fenestrations - small holes) connecting luminal to extraluminal side:

What happens:
- liquid portion of your blood (plasma) carrying solutes is free to diffuse OUT of a BLOOD VESSEL & come into CONTACT with SKELETAL MUSCLE CELLS for ex & similarly, material can diffuse INTO these blood vessels (very, very leaky)

60
Q

Describe circulation IN THE CNS

A 
endothelial cells (within blood vessels) joined by TIGHT JUNCTIONS
- means cells itself are connected by proteins that DON'T permeate the movement of solute or liquid b/t those 2 cells

surrounded by ASTROCYTE (within CNS) ENDFEET

  • form structures called endfeet that are lil projections that surround all the blood vessels
  • joined by tight junctions –> solute is NOT free to move b/t those joints - it forms a protective layer (blood vessels are wrapped)

end result of that is, hydrophilic substances (water soluble - even glucose) in the blood, must be transported across those cellular layers to make it into the interstitial fluid & eventually into the neuron

  • same goes for signalling molecules - like peptide based hormone - have to be transported from blood to interstitial fluid
  • likewise any materials secreted by neurons/glial cells must be transported to get into the circulation
  • hydrophilic molecules (like ex ethanol) is fat soluble & can diffuse across those cell membranes & directly contact neurons
61
Q

Describe which type of molecules can diffuse across the blood brain barrier

A 
only LIPOPHILIC (fatty - fatty soluble) molecules can diffuse across (freely pass from the circulation into the interstitial fluid surrounding neurons)
- steroids, ethanol, nicotine, Benadryl

POLAR, HYDROPHILIC molecules can only cross via transporters
- insulin, glucose, Na+

62
Q

Describe Benadryl

A
  • the antihistamine in this can diffuse across those cell membranes & contact neurons
  • allergy medicine (meant to have a proiferal effect)
  • but b/c it is lipophilic it can move from the circulation & come into contact with neurons therefore it can actually inhibit the activity of neurons by acting @ histamine receptors
  • if you’re effecting those histamine receptors in the brain that is 1 of the reasons why benadryl causes drowsiness b/c the histamine antagonist is actually acting on neurons where its not meant to act
63
Q

Spinal cord

A
  • major pathway b/t the brain & skin, muscle, joints, & organs (parts of the body we call the periphery)
  • 4 levels
  • organized into segments
  • spinal cord has its own internal circuitry to mediate simple reflexes & generates complicated control programs, such as rhythmic patterns used for walking
64
Q

What are the 4 levels of the spinal cord?

A
  • cervical (parts of the spinal cord in your neck), thoracic (“” check), lumbar (“” lower back), sacral (also coccygeal) (“” very lower back, near pelvis)
  • 31 pairs of spinal nerves in total
  • after L1-L2, the SC consist of thick elongated nerve roots called CAUDA EQUINA
65
Q

What are the 4 levels of the spinal cord?

A
  • cervical (parts of the spinal cord in your neck), thoracic (“” check), lumbar (“” lower back), sacral (also coccygeal) (“” very lower back, near pelvis)
  • 31 pairs of spinal nerves in total
  • after L1-L2, the SC consist of thick elongated nerve roots called CAUDA EQUINA
66
Q

What is cauda equina?

A

after L1-L2, the SC consists of thick elongated nerve roots

  • “horsetail” - connection of nerve roots
  • there are a lot of axons that have diverged from the spinal cord up higher & by the time you get to this lower region there isn’t a whole lot left
67
Q

What are the segments that the spinal cord is organized into?

A

each segment has bilateral (2) sets of roots

  • dorsal (sensory)
  • ventral (control/motor)
68
Q

Ex: Pateller reflex

A

the circuity req for this doesn’t req your brain @ all, it ONLY requires the axons that are innerating those muscles, neurons in the spinal cord & the axons exiting the spinal cord
- doesn’t req anything above the level of your spinal cord

69
Q

For simple rhythmic movements:

A

all the circuity for that is located in the spinal cord - so walking for ex

  • the circuity req for the act of walking (simple rhythmic movement of your legs - coordinated movement of your legs) all of that is in place with the spinal cord itself
  • the input that’s needed for the control of walking comes from your brain & levels above your spinal cord
70
Q

The meninges surround the _____ _____ as well so it gets protected

A

spinal cord

71
Q

Roots

A

nerves that contain #’s of axons

- can differentiate which is which simply by the presence of this enlargement

72
Q

Ventral root

A
  • carrying Efferent axons

- those axons will control skeletal muscle, function of some of the organs etc.

73
Q

Dorsal root

A

carry sensory axons, carrying info into the CNS

- ENLARGED is ALWAYS the dorsal root (found in your back)

74
Q

Autonomic ganglion

A

contain neurons that regulate the ANS or are an intrenget part of the ANS

75
Q

Spinal nerve

A

point that they (roots?) join up

76
Q

Dendrites

A
  • found in the periphery

- contains various kinds of sensors for (temp, touch etc)

77
Q

Axon

A

a bunch of these will come together to form these spinal nerves

78
Q

Pseudounipolar sensory neurons

A
  • b/c they only have 1 process that’s exiting the cell body

- have an axon neuron that is specialized for carrying info over long distances

79
Q

White matter in the spinal cord

A

formed by myelinated axons

- REVERSED outside now (opp. from brain)

80
Q

Grey matter in the spinal cord

A

formed by neuronal cell bodies, dendrites & unmyelinated synapses, etc
- REVERSED now, inside (opp. from brain)

81
Q

Dorsal root the spinal cord

A 
carries sensory (afferent) info to CNS
- enlargement that contains CELL BODIES of those sensory neurons
82
Q

Ventral root in the spinal cord

A

carries motor (efferent) info to muscles & glands

83
Q

2 roots will merge & form a…

A

spinal nerve

84
Q

What is each segment of the spinal cord gonna have?

A

each segment of the spinal cord is gonna have a pair of dorsal roots & a pair of ventral roots & these will merge together & eventually form a spinal nerve

85
Q

Dorsal root ganglion

A

enlargement that contains sensory neuron cell bodies

86
Q

Visceral sensory nuclei

A

neurons part of a local processing circuit - meant to process sensory info that is coming from your viscera (from various ORGANS for ex)

87
Q

Somatic sensory nuclei

A

2nd order sensory neurons (means they receive a synapse from the 1st order primary sensory neurons)
- cell bodies in there receive some of the sensory info

88
Q

Autonomic efferent nuclei

A
  • send axons out through ventral roots

- contribute to the autonomic control of your organs

89
Q

Somatic motor control nuclei (skeletal muscle)

A
  • in the very ventral aspect

- control SKELETAL MUSCLE

90
Q

What are the 2 white matter tracts?

A

Ascending tracts:

  • on dorsal surface
  • carry sensory info

Descending tracts:
- info on axons that will control skeletal muscle & organs

91
Q

What makes up the brainstem?

A
  1. Midbrain
  2. Pons, &
  3. Medulla

cerebellum NOT considered brainstem

92
Q

Brainstem

A

(phylogenetically) oldest region of the brain

transition to the SC

consists of

  • midbrain
  • pons
  • medulla
  • (NOT CEREBELLUM!!!)

most of cranial nerves (10/12 pairs of nerves) arise from brain stem

  • pairs of nerves emerging from CNS that carry SENSORY INFO (from eyes, ears, sense of balance, taste - some carry info that controls your mouth, tongue, movement of your eyes etc)
  • sensory, motor (that control the functioning on your organs), or both (either carry sensory info back & motor info out & some are mixed - carry both)
93
Q

Reticular formation (part of brainstem)

A
  • receives & integrates incoming sensory input
  • plays critical role in AROUSAL (wakefulness - whether or not your awake & whether or not you can focus on certain kinds of info)
  • gives rise to groups of DIFFUSE MODULATORY NEURONS
  • means diffused, so there is no real structure to this part
  • diffused collection of cell bodies
94
Q

Medulla (part of brainstem)

A

contains neuronal clusters (nuclei) that control (these bodily functions) HEART & BLOOD VESSEL function, RESPIRATION, & many DIGESTIVE functions
- better organized

95
Q

Pons (part of brainstem)

A

acts as a RELAY station for CEREBELLUM & CEREBRUM: plays role in regulating MUSCLE REFLEXES involved in EQUILIBRIUM & POSTURE

96
Q

Cerebellum

A

key part in brain for your ability to maintain POSTURE, sense of BALANCE & EQUILIBRIUM

97
Q

Cerebrum

A

integrating station

- info flows back & forth between this & cerebellum - allowing a sense of equilibrium in your posture

98
Q

Midbrain

A
  • critical relay for visual (from eyes) & auditory (from ears) info
  • governs movement of the eyes (dilation & constriction of your pupils)
  • gives rise to groups of DIFFUSE MODULATORY NEURONS
99
Q

Diffuse modulatory systems

A

long, slow regulation of behaviour of neurons & its usually through the actions of GPCR

for norepinephrine, dopamine, & serotonin

  • group of neurons in here (only a few 1000 of those neurons - but they send axons nonetheless through the brain, through the cerellum & down through the spinal cord)
  • don’t act to directly stimulate AP’s, but they have subtle modulatory influences on the electrical behaviour of the way neurons work

for acetylcholine
- similarly, several 100 000 but these diffuse modulatory neurons that spread their axons all throughout the brain - don’t just project to a single location

100
Q

Cerebellum

A

processes sensory info from muscles, joints, vestibular system, eyes

  • integrates POSITION & MOVEMENT of body with intent to move body
  • important in maintaining BALANCE & CONTROLS EYE MOVEMENTS (if you close your eyes & stand on 1 foot - sense of balance is inhibited drastically & that is b/c of info coming through your visual system & being integrated within your cerebellum)
  • enhances MUSCLE TONE & COORDINATES skilled, VOLUNTARY movements (reach across table to grab a pencil)
  • plays a role in planning & initiating VOLUNTARY activity by providing input to cortical motor areas (preplan a coordination before you do it)
  • STORES PROCEDURAL MEMORIES (motor learning - learn how to do something, ex: learning to shoot a puck in top shelf (practiced) these procedural memories are stored in the cerebellum)

also has recently discovered function in cognition (ability to think) & emotional processes

derives from same developmental tissue from the pons (even though it is NOT part of brainstem)

POSITION OF THE BRAIN THAT COORDINATES THE EXECUTION OF MOVEMENT

101
Q

Thalamus

A
  • main relay centre for most types of info
  • receives info from almost every area of the CNS, & sends info to these same areas
  • sensory, emotional, motor, arousal
  • all have a synaptic relay or synapse at the level of your thalamus

PORTION OF THE BRAIN THAT SERVES AS A RELAY STATION FOR INFO GOING TO & FROM HIGHER BRAIN CENTERS

102
Q

Why do we need a synapse there? Why do we need a relay?

A
  • you might think it will be more efficient if you just send an axon from point A to point B, instead of sending it to from a relay in the thalamus 1st or from the synaptic connection there
  • whole point of having more synaptic connections is yes there is a loss of speed b/c there has to be a synapse, but you get info processing/integration, so you allow info that’s going to the cortex to be integrated with other info from other areas (helps contextualize your info)
103
Q

Hypothalamus

A

below thalamus

brain area most involved in directly regulating internal environment (internal)

REGION OF THE BRAIN THAT CONTAINS CENTERS FOR BEHAVIOURAL DRIVES & PLAYS A KEY ROLE IN HOMEOSTASIS

104
Q

Hypothalamus functions

A
  • controls body temp
  • controls thirst & urine output
  • controls food intake
  • controls anterior pituitary hormone secretion
  • produces vasopressin & oxytocin (neuroendocrines)
  • controls uterine contractions & milk ejection
  • serves as a major ANS coordinating center
  • plays role in emotional & behaviour patterns, including reproduction, SEXUAL ORIENTATION?
105
Q

Hypothalamus & sexuality

A

in 1991 Simon LeVay published a paper indicating a morphological difference in a nucleus of the hypothalamus b/t gay & straight men (INAH3 - small area of hypothalamus)
- the area in gay men was anatomically more similar to females

suggested “sexual orientation has a biological substrate”

  • often misinterpreted
  • very controversial findings
  • LeVay accused of being biased (b/c he is gay)
106
Q

Cerebrum

A

LARGEST & most DISTINCT part of human brain (makes up about 80% of total brain weight)
- our intelligence really comes about b/c of a massive enlargement of our cerebrum - compared to other animals (especially other mammals)

folded, showing gyri & sulci (peaks & valleys)
- these are used as landmarks

evolutionarily, the newest

several parts

  • cortex
  • white matter
  • basal ganglia
  • limbic system

LARGEST REGION OF THE BRAIN

107
Q

What are the several parts of the cerebrum?

A
  • cortex
  • white matter
  • basal ganglia
  • limbic system
108
Q

Cortex

A

OUTER surface is highly convoluted cerebral cortex

  • HIGHEST, MOST COMPLEX INTEGRATING area of the brain
  • plays key role in most SOPHISTICATED neural functions (math, language, music)

each half of cortex divided into 5 major lobes

LITERALLY, BARK; THE OUTER OR SURFACE PORTION OF AN ORGAN

109
Q

What are the 5 major lobes that each half of cortex is divided into?

A
  1. occipital
  2. temporal
  3. parietal
  4. frontal
  5. insular*
110
Q

What is “special” about the insular lobe?

A

for 2 reasons:

  1. it’s not obvious looking @ the brain from the surface view
  2. sometimes textbooks don’t include it at all
111
Q

Frontal Lobe

A

Skeletal muscle movement

  • primary motor cortex
  • motor association area (premotor cortex)

prefrontal association area

112
Q

Describe premotor neurons

A

are critically involved in PLANNING OF MOVEMENT

  • get info from BG, cerebellum & somatic sensory cortex
  • activation of these neurons is what triggers activation of neurons within your SC; sends neurons down into SC to those motor neurons & ultimately let you grab your coffee cup

thinking of picking up coffee mug then activate these

  • these neurons become activated & fire APs & process info that they need to do to help coordinate movement
  • proper signals will get sent from neurons to SC to activate right set of motor neurons to grab cup
113
Q

Sulci

A

fold

114
Q

Gyri

A

Humps

115
Q

Central Sulcus

A

frontal & parietal lobe are differentiated by this one major groove (central sulcus)

  • anterior to that is gonna be the frontal lobe
  • posterior to that is gonna be the parietal lobe
116
Q

Parietal Lobe

A

processing textures, touch, temp info from your skin

primary somatic sensory cortex

& sensory association area

117
Q

Primary somatic sensory cortex

A

sensation of processing of sensory info from you body

  • have the ability to discriminate b/t a smooth surface & a rough surface
  • 1st area of processing
118
Q

Sensory association area

A

adjacent area

  • understand more of the properties of what you’re touching
  • 2nd area of processing
  • able to associate smooth/rough surface with other simultaneous stimuli & make a judgement as to what that particular stimulus is
  • different properties of keyboard your touching
119
Q

Occipital Lobe

A

vision

visual cortex

  • 1st area of processing
  • “this item is red” or “this item is round”

visual association area

  • 2nd area of processing
  • “oh, it’s a red ball”

allow increase level processing of the info acquired in the visual cortex

120
Q

Temporal Lobe

A

Hearing

Auditory cortex
- 1st place where auditory info is transmitted

Auditory association area
- then goes here to understand & process

121
Q

Insular Cortex

A

“insulated” - it’s hidden, it’s sheltered

taste - gustatory cortex

smell - olfactory cortex

122
Q

What is the Ideal of lateralization?

A

2 halves of the brain are NOT identical,

  • left-handed persons brain is NOT a mirror image of right-handed person’s
  • for most people language processing, math processing occur on the left side
  • 95% right handed people left dominant for language (means their language is processed on the left side of the brain - this doesn’t necessarily mean that theres language processing on the right side - in fact there is very little on the right side of most peoples brain & its not reflective in whether or not your left handed or right handed)
  • but only 20% left handed people right dominant for language; many lefties process language on both sides (i.e. it’s complicated)

**Take home message: often many functions are localized to one side of the brain, not always bilaterally localized

  • for most people spatial recognition (if you were blind folded & someone put you into a building & you recognized where you were), face recognition, aspects of emotion processing & artistic functions occur on the right side (1 side of the brain) - not always true
123
Q

Is right & left brain person a thing?

A

lateralization does NOT refer to right brain person (creative, artistic) vs left brain (logical & analytical): this idea from 1960’s is considered scientifically unsound

124
Q

Explain how NOT every function is lateralized

A

some things are localized to one side or the other, some things are found on both sides

ex’s on page 56

125
Q

What is one of those things that is lateralized?

A

the process of language

126
Q

Areas are connected by reciprocal connections…

A
  • are axons that go from W’s to B’s & vice versa

- those 2 areas communicate to each other

127
Q

Where does input for language processing come from?

A

audio (listening to language) or visual (reading language) info

128
Q

Describe the path of sensory input

A

sensory input goes from audio or visual cortex to Wernicke’s, then to Broca’s
- following integration b/t these 2 areas, info from Broca’s to motor cortex to initiate spoken or written action

129
Q

Aphasia

A

inability to comprehend or formulate langauge

130
Q

Damage to Wernicke’s area:

A
  • difficulty understanding spoken or visual language (Receptive aphasia)
  • -> understanding when someone is speaking to you or writing or both or 1 or the other
  • speech may be nonsensical b/c of trouble connecting words with meaning (word salad, Jargon aphasia)
  • have real words & the real words can come out of their mouth perfectly formed, but they can’t string them together in a proper sentence
  • a bunch of words will just come out of their mouth, but there is no logical meaning for any of that
131
Q

Damage to Broca’s area:

A
  • often can interpret simple words or sentences, but may have trouble with more complicated ones with several elements
  • -> might have trouble with the “red cat ran up the big tree to catch a squirrel” - with numerous elements in this sentence
  • difficulty expressing ideas: “can’t get a sentence out” (Expressive aphasia)
  • -> know what they want to say inside their head, but just cannot get those words out, either spoken or in writing or both
  • words (come out) “distorted”
  • -> (mangled sounds of the words)
  • just a disconnect b/t the ability to form those words into a language & what happens with their mouth, can’t connect how to make a word & make that particular sound
132
Q

Damage to Broca’s area:

A
  • often can interpret simple words or sentences, but may have trouble with more complicated ones with several elements
  • -> might have trouble with the “red cat ran up the big tree to catch a squirrel” - with numerous elements in this sentence
  • difficulty expressing ideas: “can’t get a sentence out” (Expressive aphasia)
  • -> know what they want to say inside their head, but just cannot get those words out, either spoken or in writing or both
  • words (come out) “distorted”
  • -> (mangled sounds of the words)
  • just a disconnect b/t the ability to form those words into a language & what happens with their mouth, can’t connect how to make a word & make that particular sound
133
Q

Basal Ganglia

A
  • “Ganglia” are collections of cell bodies (=nuclei)
  • there are several components of the basal ganglia
  • the neurons within basal ganglia communicate with each other, & with other brain areas
134
Q

Components of the basal ganglia form a complex circuit b/t the…

A

motor cortex, premotor cortex, cerebellum, thalamus, & other areas

135
Q

Explain the 2 main diseases of basal ganglia

A

loss of any parts of the basal ganglia is devasting

Parkinsons disease: loss of dopaminergic neurons in BG

  • causes tremors, loss of ability to move (initiate a movement - difficulty getting up from a chair), cognitive deficits
  • MJF (Micheal J Fox, Rush Limbaugh)
  • if you overstimulate/overmedicate you can cause Huntington like symptoms

Huntington’s disease is loss of cholinergic neurons in BG (this activates the neurons that are lost in Parkinson’s)
- causes uncontrollable movements (chorea - Latin to dance), loss of coordination, dementia (similar to PD)

136
Q

Limbic System

A

considered phylogenetically oldest part of the cerebrum

  • includes amygdala, hippocampus, cingulate gyrus
  • strongly connected with other areas, such as thalamus, hypothalamus, & parts of the midbrain & brainstem
  • links higher processing with primitive emotions such as fear, aggression, reward, social & sexual behaviour - “animal brain”
137
Q

Ex: See a bear in the woods

A
  1. Sensory stimuli
  2. Cerebral Cortex - integration occurs within the association areas of the cerebral cortex
    - Bear! - see bear (visual)
  3. Integrated info
  4. Limbic system creates emotion
    - critical component for regulating basic emotional responses
    - Fear!
    - processes & integrates - sends info back “OMG that’s a bear, if i don’t move it will eat me!)
    - feedback creates awareness of emotions
  5. Hypothalamus & brain stem
    - homeostatic response
  6. Initiate
    - Somatic motor responses (both voluntary & unconscious - irresistible urge to run)
    - Autonomic responses (fight or flight)
    - Endocrine responses
    - Immune responses (if there is a long term stress)
138
Q

Diseases & lesions of the CNS: damage to frontal lobe

A

Phineas P. Gage

  • worked on the railroad
  • his job was to put dynamic down with the pole
  • tamped down dynamic & it sent steel rod through his head
  • abolishes large part of frontal cortex
  • doctor was surprised he was alive
  • made the recovery
  • before he was smart, easy to get along with
  • *after personality completely changed
  • swore, not easy going, angry, difficult to get along with, changed jobs lots
  • historically imp. case
  • things we learn from a single patient stimulate a whole area of resource (like H.M. hippocampus)

Human Physiology 1 (32 decks)

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