clinical + research techniques for investigating the nervous system

Question 1

for investigating neuroscience, what are the clinical methods?

Answer 1

clinical history + exam
neuropathology
imaging
electrophysiology
chemical studies

Question 2

what questions are asked when taking the patients history?

Answer 2

age
sex
handedness
when, what and where is the problem
associated conditions
medication, allergies
family history
developmental history

Question 3

what is observed/taken in a patients physical exam?

Answer 3

mental status (awake or comatose)
language (receptive and expressive)
cranial nerve exam
cerebellar exam
strength
tone (stiff or flexible)
reflexes
gait

Question 4

cranial nerves are important for what part of the brain’s assessment?

Answer 4

brainstem

Question 5

cranial nerves are typically tested in what kind of patient?

Answer 5

comatose

Question 6

what is an example of a cranial nerve test they use that does not require a MRI or CT scan?

Answer 6

pupillary response: optic nerve, constricts (small) pupil

Question 7

what are some tests to discover cerebellar signs that do not require MRI or CT scans?

Answer 7

nystagmus (eye jerk)
ataxia or unsteady gait (jack sparrow walk)
slurred speech
dyadiadochikynesia (cannot perform rapid alternating muscle movement)

Question 8

what is the sensory response to pain?

Answer 8

withdraw

Question 9

what is the pathway of a sensory response to heat?

Answer 9

hot object -> sensory receptors -> spinal cord -> muscle contracts and withdrawn parts being stimulated

Question 10

what is the name for the type of reflexes that are normal in babies up until a certain age?

Answer 10

primitive

Question 11

what do primitive reflexes help us identify?

Answer 11

brain lesions if reflex is there when it should be gone or does not exist completely

Question 12

what are some examples of primitive reflexes in babies?

Answer 12

tonic neck reflex, grasp reflex, step reflex, crawl reflex

Question 13

what is the deep tendon reflex?

Answer 13

hammer on knee, leg kicks up

Question 14

the deep tendon reflex can be triggered by?

Answer 14

stretch receptors

Question 15

reflex responses help doctor to?

Answer 15

localize where the lesion is

Question 16

if there is an increased reflex, this suggests that there is a lesion..?

Answer 16

above the level tested

Question 17

if there is a decreased reflex, there is a lesion..?

Answer 17

at the level or below the level tested

Question 18

what is clonus?

Answer 18

brain or spine injury above lumbar

Question 19

can clinical methods (neurological exam) show exactly where the lesion is?

Answer 19

no

Question 20

the methods that were initially used to examine where brain lesions were was?

Answer 20

pathological post-mortem examination (brain after death)

Question 21

what is brocas area responsible for?

Answer 21

speech

Question 22

damage of the frontal left cortex associated with?

Answer 22

difficulty speaking

Question 23

established lateralization of the lingusitixc funcgtion mainly in what hemisphere for right handed individuals?

Answer 23

left hemisphere

Question 24

pathology can identify?

Answer 24

post-mortem brain changes

Question 25

pathology can now give the?

Answer 25

subtype of disease

Question 26

can pathology show the types of cells?

Answer 26

yes

Question 27

pathology requires a sample, so how have we tried to avoid this?

Answer 27

brain imaging

Question 28

what is a CT scan?

Answer 28

image with series of x-ray slices/images put together

Question 29

what are the advantages of a CT scan?

Answer 29

- cheap and fast - most common scanning method - good at detecting blood

Question 30

what are the disadvantages of a CT scan

Answer 30

- limited resolution - can miss acute stroke lesions - not as precise

Question 31

what is an MRI scan?

Answer 31

a magnetic field where a radio signal moves a sequence of cells

Question 32

what are the advantages of an MRI scan?

Answer 32

- very fine details of anatomy - multiple sequences can be used to detect specific problem

Question 33

what are the disadvantages of an MRI scan?

Answer 33

- take an hour - children require sedation - cost - limited availability due to cost

Question 34

what was one of the first applications of the MRI?

Answer 34

volume measurement

Question 35

if someone has alzheimers, will they have a larger brain volume or a smaller brain volume?

Answer 35

smaller! experience shrinkage

Question 36

what are two types of MRI sequences (______ weighted)

Answer 36

diffusion-weighted and perfusion weighted

Question 37

what is a diffusion weighted MRI

Answer 37

water distribution - diffusion of protons in water along fibre tracks

Question 38

what is a perfusion rated MRI?

Answer 38

blood comes in and flow

Question 39

MRI methods that use diffusion methods are used to examine tracts in patients with what kind of problems?

Answer 39

- brain tumors - illness (depression) - developmental disorder (autism) - aging

Question 40

what is magnetic resonance spectroscopy (MRS)?

Answer 40

the ratio of chemicals in a certain region

Question 41

what are the advantages of MRS

Answer 41

- provides quantification of specific metabolites or neurotransmitters in specific regions of interest

Question 42

what are the disadvantages of MRS?

Answer 42

- cannot from blood or urine

Question 43

does CT, MRI, or MRS show the vascular aspect (arteries, veins) of the brain?

Answer 43

no!

Question 44

what is an angiogram?

Answer 44

radio-opaque substance, or dye, to make the blood vessels visible under x-ray

Question 45

what are the advantages of angiograms?

Answer 45

very precise mapping of the blood vessels (even smaller ones)

Question 46

what are the disadvantages of angiograms?

Answer 46

requires a catheter to put into the blood vessels and injection of dye which can lead to vessels rupture or allergic reaction

Question 47

sometimes the problem does not affect the structure of the brain but..?

Answer 47

the function of the brain cells

Question 48

what is an electroencephalogram (EEG)?

Answer 48

difference in electrical potentials generated by the brain

Question 49

what are the advantages of an EEG

Answer 49

- high temporal resolution - useful monitoring state of arousal - cheap

Question 50

what are the disadvantages of an EEG?

Answer 50

- poor spatial resolution (no precise localization) - restricted mainly to cortical activity (cannot if it is small or deep)

Question 51

what is a common disorder EEG is used to monitor?

Answer 51

seizures

Question 52

what are grids used for in an EEG

Answer 52

put directly onto the brain for precise mapping

Question 53

what are depth electrodes used for in an EEG

Answer 53

implanted into the brain for deeper structure recording

Question 54

what is an electromyogram (EMG)?

Answer 54

patient muscle activity is recorded either at the surface or using a needle inserted within the muscle

Question 55

what are the advantages of an EMG

Answer 55

- allow to measure precisely activity in the muscle - detect when the muscle is not getting enough nerve input and is "disconnected" - can help define the type of muscle disease

Question 56

what are the disadvantages of an EMG

Answer 56

- painful needle insertion depending on placement

Question 57

what is nerve-conduction stimulus (NCS)

Answer 57

patient nerve activity is recorded by stimulating the nerve and recording the time for its connected muscle to be activated

Question 58

what are the advantages of NCS

Answer 58

- measure the precise activity of the nerve (both speed and wave form of the amount of muscle used) - can narrow down type of disease by injury pattern

Question 59

what are the disadvantages of NCS

Answer 59

can be painful with the stimulation of the nerve

Question 60

until the year 2000, what was the most used method for genetic testing?

Answer 60

karyotypes

Question 61

what do karyotype genetics allow?

Answer 61

visualize different chromosomes using a staining method and microscope

Question 62

what can copy number variation due (in relation to karyotypes)?

Answer 62

can be either a gain or loss of DNA

Question 63

what is comparative genomic hybridization (CGH)?

Answer 63

obtain patient DNA, have a reference sample plus patient DNA, compare copy of gene

Question 64

in CGH, if there is a gain in the patient, what colour is it?

Answer 64

red

Question 65

in CGH, if there is a deficit in the patient, what colour is it?

Answer 65

green

Question 66

what is an advantage of CGH

Answer 66

map changes in the copy number for the entire genome so do not need to know which gene could be affected in patient

Question 67

what is a disadvantage of CGH

Answer 67

will not be able to tell if a patient has a single base pair change

Question 68

what is next generation sequencing (NGS)?

Answer 68

multiple fragments sequenced at once, has a single base pair resolution

Question 69

what are the advantages of NGS

Answer 69

multiple sequences at the time allow for faster and cheaper sequencing of entire genome

Question 70

what are the disadvantages of NGS

Answer 70

- more error-prone than one gene - need a reference genome for aligning the fragments of colour coded sequences

Question 71

what are the clinical methods for both central and peripheral called?

Answer 71

brain metabolies

Question 72

what are the two forms of brain metabolites

Answer 72

lumbar puncture / spinal tap magnetic resonance spectroscopy (MRS)

Question 73

what is a lumbar puncture?

Answer 73

looks at the level of red blood cells, white blood cells, glucose, protein in cerebrospinal fluid (CSF)

Question 74

what are the advantages of lumbar puncture

Answer 74

- allows to get CSF, which can identify chemical, metabolic, or immune differences - less invasive than getting brain tissue

Question 75

what are the disadvantages of lumbar puncture

Answer 75

- patient must be collaborative - risk of pain and infection