Week 2 neuro sl 62-

Question 1

What matter is CNS composed of? What is each?

Answer 1

Composed of gray and white matter.
-Gray matter is made of neuron cell bodies and dendrites, is found in the cortex of the brain, and in clusters called nuclei deeper within the brain
-White matter consists of axon tracts, whose myelin sheaths give them a white colour. The axon tracts underlie the cortex and surround the nuclei

Question 2

What are the layers protecting/surrounding the brain?

Answer 2

Scalp, skull, meninges

Question 3

What are meninges and what does it include?

Answer 3

Several tough layers of connective tissues
-Pia mater: Innermost membrane, clings to surface of brain/spinal cord, follows every fold
-Arachnoid mater: Middle layer, web-like/spidery appearance
-Dura mater: Has two layers, outer, toughest protective layer

Question 4

What is the order of the layers around the brain?

Answer 4

PADSS

Question 5

How is the spinal cord protected?

Answer 5

By the same meningeal layers as the brain

Question 6

How does fluid also protect the brain? What are the two areas called?

Answer 6

Brain is protected by two fluid filled cushions against head trauma
-The outer cavity is the superior sagittal sinus (SSS), and sits under the dura matter
-The inner cavity is the subarachnoid space (SAS), located in the space between arachnoid and pia mater

Question 7

What are cavities (ventricles) of the brain and spinal cord filled with for protection?

Answer 7

Filled with cerebrospinal fluid which is similar in composition to blood plasma

Question 8

What are spinal nerves, how many are there and where?

Answer 8

Each nerve is a mixed nerve, containing both sensory and motor fibers. Fibers seperate near the attachment of nerve to spinal cord

There are 12 cranial nerves, but 31 spinal nerves
-8: cervical
-12: thoracic
-5:lumbar
-5:sacral
-1:coccygeal

Question 9

Where does the spinal cord extend from, and where do nerves enter and exit the spinal cord?

Answer 9

-Spinal cord extends from brainstem to pelvic region, ending before the vertebral column’s end
-Nerves enter and exit spinal cord between the vertebrae

Question 10

How do interneurons communicate and what happens?

Answer 10

Interneurons communicate along spinal cord, allowing afferent sensory stimuli to travel up or down it’s length

Question 11

Explain upper and lower motor neuron damage in terms of knee jerk reflex test.

Answer 11

-If there’s lower motor neuron damage, reflex will be diminished
-If there’s upper motor neuron damage, reflex will be exaggerated because loss of inhibitory inputs means nothing will regulate the reflex because it’s damaged

Question 12

What are the three primary vesicles of the brain that occur from conception to week 4 and explain.

Answer 12

Forms during embryonic development. By week 4 after conception, three sweellings appear the front of the neural tube which develops into brain.
-Prosencephalon (forebrain)
-Mesencephalon (midbrain)
-Rhombencephalon (hindbrain)

Question 13

What are the 5 regions that were modified from the 3 primary vesicles? When does this occur?

Answer 13

5th week
-Prosencephalon: telencephalon and diecephalon
-Mesencephalon: mesencephalon
-Rhombencephalon: Metencephalon and myelencephalon

Question 14

Slide on adult derivatives of brain!!

Question 15

What is a hemmorhage stroke and an ischemic stroke?

Answer 15

Hemmorhagic stroke: Blood leaks into the brain
Ischemic stroke: Clot stops blood supply to an area of the brain

Question 16

What do the midbrain and hind brain contain and why?

Answer 16

Midbrain and hindbrain contain many relay centers for sensory and motor pathways, and are important in brains control of skeletal movements

Question 17

What is the cerebrum and what are the 5 regions?

Answer 17

Consists of left and right hemispheres, whihc are connected by corpus callosum. The cerebrum handles higher function (thinking, memory).
5 regions:
Frontal lobe, occipital lobe, parietal lobe, temporal lobe, insula

Question 18

What does the occipital lobe do?

Answer 18

Vision and coordination of eye movements

Question 19

What does the Frontal lobe do?

Answer 19

Motor control

Question 20

What does the parietal lobe do?

Answer 20

Processes somatesthic sensation from cutaneous (skin), muscles, tendons, and joints

Question 21

What does the temporal lobe do?

Answer 21

Interpretation and association of auditory and visual information

Question 22

What does the insula do?

Answer 22

Deep brain region within lateral sulcus, between frontal and temporal lobes. Helps with memory, sensory integration and visceral responses. It processes smell, taste, sound, pain, etc

Question 23

What is cerebral lateralization?

Answer 23

Each hemisphere of the brain processes different inputs, but they communicate through the corpus callosum.

Question 24

What did experiments reveal about the hemispheres of the brain?

Answer 24

Experiments revealed that each hemisphere excels at certain tasks, leading to concepts of cerebral dominance, cerebral lateralization and handedness

Question 25

What does damage to the right hemisphere cause?

Answer 25

Difficulty with spacial concepts and maps

Question 26

What does damage to the left hemisphere cause?

Answer 26

Severe speech problems, but may still have ability to sing

Question 27

What is this neurotransmitter associated with? Adrenaline?

Answer 27

Fight or flight

Question 28

What is this neurotransmitter associated with? Noradrenaline?

Answer 28

Concentration

Question 29

What is this neurotransmitter associated with? Dopamine?

Answer 29

Pleasure

Question 30

What is this neurotransmitter associated with? Seratonin?

Answer 30

Mood

Question 31

What is this neurotransmitter associated with? Gaba?

Answer 31

Calming

Question 32

What is this neurotransmitter associated with? Acetylcholine?

Answer 32

Learning

Question 33

What is this neurotransmitter associated with? Glutamate?

Answer 33

Memory

Question 34

What is this neurotransmitter associated with? Endorphins

Answer 34

Euphoria

Question 35

What is the cerebral cortex and what can damage to this area (prefrontal cortex) do?

Answer 35

Cerebral cortex is a gray matter layer covering the cerebrum and the cerebellum, divided into left and right hemisphere. Important in emotion and memory -Damage to this area can cause severe impulsive, even sociopathic behaviour

Question 36

What is the thalamus?

Answer 36

A relay centre for all sensory information (except smell) on it's way to the cerebrum. Promotes alertness and causes arousal from sleep in response to strong sensory stimuli

Question 37

What does the epithalamus contain?

Answer 37

Dorsal segment contains pineal gland which secretes melatonin (sleeping hormone and helps regulate circadian rhythm)

Question 38

Where is the thalamus in the brain?

Answer 38

In 4/5ths of the diencephalon

Question 39

Where is the epithalamus located?

Answer 39

Dorsal segment of the diencephalon

Question 40

Where is the hypothalamus located?

Answer 40

Above the optic chiasm, and in the lowest part of the diencephalon

Question 41

What does the hypothalamus do?

Answer 41

Is the site of master circadian clock (SCN), which receives light input to know how to function Regulates daily processes: -Hunger, thirst -Body temp -Hormone secretion (from pituitary gland) -Sleep and wake cycles

Question 42

What do the midbrain and hindbrain contain?

Answer 42

Contain many relay centers for sensory and motor pathways, and important in brain's control of skeletal movements

Question 43

What are the two dopaminergic systems in the midbrain?

Answer 43

nigrostriatal dopamine system, and mesolimbic system

Question 44

What is the nigrostriatal dopamine system? When does parkinson's occur?

Answer 44

Involved in controlling movements -parkinsons occur when dopaminergic neurons in substantia nigra degenerate

Question 45

What is the mesolimbic system? What can overactivity in this region cause?

Answer 45

Involved in emotional reward. Substances like alcohol, amphetamines, cocaine, marijuana and morphine increase activity of dopaminergic neurons. Plays a role in addiction Overactivity in this region may contribute to schizophrenia

Question 46

What is the cerebellum composed of, and what does it do?

Answer 46

-Composed of over 50 billion neurons, and gray and white matter -Monitors and refines motor activity initiated elsewhere. It does this by receiving input from proprioceptors (in joints, tendons and muscles) and motor signals from the cerebral cortex, helping to coordinate movement

Question 47

What is the medulla required for?

Answer 47

Required for regulation of breathing, CV responses

Question 48

What must pass through the medulla, involving the brain and spinal cord?

Answer 48

All ascending and descending fiber tracts providing communication between spinal cord and brain must pass through the medulla

Question 49

What is the courchesne theory of overstimulation?

Answer 49

Autistic children seem antisocial because they shun external stimulation since the cerebellum can't take it. Repetitive behaviour is calming ot thier brain

Question 50

What are symptoms of aspergers and PDD?

Answer 50

some range of hyper focus, mild movement disroder, lack of social cues