B2.021 Altered Mental Status in an Elderly Patient

Question 1

what characterizes the darker areas of brain matter?

Answer 1

cell bodies in high density

Question 2

what characterizes the light areas in brain matter?

Answer 2

signaling pathways, axons of neurons present (no cell bodies)

Question 3

what is a resting membrane potential?

Answer 3

the typically negative electrical charge of the cytoplasm of the cell

Question 4

what is a synapse?

Answer 4

the interaction between neurons

Question 5

how is information from sensory systems transmitted?

Answer 5

all information is encoded into action potentials, frequency changes in potentials represent different sets of information

Question 6

what are motor neurons?

Answer 6

neurons that act on muscle cells

Question 7

what are interneurons?

Answer 7

local circuitry between neurons

Question 8

what are sensory neurons?

Answer 8

receive information from periphery

Question 9

why might some neurons not have dendrites?

Answer 9

simplistic structure = simplistic function, transfer information quickly along axon from point A to point B

Question 10

what might some neurons not have an axon?

Answer 10

interact exclusively with other neurons through dendrites

Question 11

why do cerebellar Purkinje cells have a large network of dendrites?

Answer 11

receive 200000 synapses from other neurons

Question 12

what are glial cells?

Answer 12

cells that fill space between neurons in CNS, 10x more glial cells than neurons

Question 13

what are 5 functions of glial cells?

Answer 13

1. maintain ionic balance
2. modulate the rate of nerve signal propagation
3. uptake of neurotransmitters
4. regulate recovery of neurons from injury
5. form the epithelium in the ventricles

Question 14

what are 4 types of glial cells?

Answer 14

1. astrocyte/satellite cell
2. oligodendrocyte/schwann cell
3. microglial cell
4. ependymal cell

Question 15

what is the function of myelin?

Answer 15

accelerates transmission of action potentials

Question 16

what are neurotransmitters?

Answer 16

molecules used by neurons to communicate with one another

Question 17

what are the two types of synapses?

Answer 17

chemical and electrical

Question 18

what is the distance between the pre-and post-synaptic membrane in a chemical synapse?

Answer 18

50 nm, relatively large and causes a diffusion delay of 1-2 ms

Question 19

what ion channel activates vesicle functions?

Answer 19

Ca2+

Question 20

what enzyme is responsible for the degradation of ACh?

Answer 20

ACh esterase

Question 21

what are two mechanisms for removal of neurotransmitters?

Answer 21

degradation and removal/re-uptake

Question 22

what types of receptors bind ACh?

Answer 22

nicotinic

Question 23

what are the types of postsynaptic potentials?

Answer 23

excitatory (EPSP) and inhibitory (IPSP)

Question 24

what characterizes an EPSP?

Answer 24

depolarization of the membrane due to the transient increase in Na+ or Ca2+ conductance

Question 25

what characterizes an IPSP?

Answer 25

hyperpolarization of the membrane due to the transient increase in K+ or Cl- conductance

Question 26

what is spatial summation?

Answer 26

simultaneous inputs from two locations

Question 27

what is temporal summation?

Answer 27

quick succession of inputs in one location

Question 28

what is the distance between the pre-and post-synaptic membrane in an electrical synapse?

Answer 28

3.5 nm, no response delay

Question 29

characterize an electrical synapse

Answer 29

1. direct passage of molecules/ions
2. no delay in transduction
3. conduction in both directions
4. inactivated by H+ or Ca2+
5. useful in reflex pathways and during development

Question 30

what are the two types of cortical areas and their respective makeup %?

Answer 30

primary and sensory motor areas - 25%

association cortices- 75%

Question 31

what does the association cortex do?

Answer 31

integrate information from various brain regions, influence a broad range of behaviors/functions

Question 32

what is declarative memory?

Answer 32

available to consciousness, can be described in words

Question 33

what is procedural memory?

Answer 33

not available to consciousness, cannot be described in words

Question 34

what are types of declarative memories?

Answer 34

daily episodes, words and their meanings, history

Question 35

what are types of procedural memories?

Answer 35

motor skills, associations, priming cues, and puzzle solving skills

Question 36

where is short term declarative memory storage?

Answer 36

hippocampus and related structures

Question 37

where is long term declarative memory storage?

Answer 37

cortical sites: wernickes area for word meanings, temporal cortex for memories of objects and faces

Question 38

where is long term procedural memory storage?

Answer 38

cerebellum, basal ganglia, premotor cortex, and other sites related to motor behavior

Question 39

what are the two types of amnesia?

Answer 39

anterograde- inability to establish new memories

retrograde- inability to retrieve old memories

Question 40

when does retrograde amnesia occur?

Answer 40

damage to cortical areas

Question 41

what characterizes anterograde amnesia?

Answer 41

normal IQ, no difficulty in perception, abstract thinking is normal, declarative long term memory is normal, procedural memories are normal, short term declarative memory is compromised

Question 42

what are two treatments for AD symptoms?

Answer 42

AChE inhibitors and NMDA receptor antagonists