SPAUD 210: 4/17

-70 mV

what charge is resting potential?

non-permeable

what is the membrane of an axon like at resting potential?

K+ (potassium)

at resting potential, which ions make up most of the inside of the axon?

Na+ (sodium

at resting potential, which ions make up most of the outside of an axon?

action potential

a change in electri al potential that occurs when the cell membrane is stimulated adequetely to permit ion exchange

threshold level

a critical level which, if reached, will produce a sudden change in the membrane polarity for Na+ ions

-55 mV

what is threshold level?

the membrane becomes permeable, sodium rushes in through the gates

what happens to the membrane as a response to the threshold level being met?

depolarization

when the threshold level is reached, the Na+ ion gates open and allow a large number of Na+ ions to flood in and raise the intercellular potential

+40 mV

what is the level reached at depolarization?

repolarization

what happens after depolarization?

Sodium (Na+) channels

which channels open with depolarization?

Potassium (K+) channels

what channels open with repolarization?

repolarization

during this time, K+ channels open and K+ ions go out to the intercellular space

absolute refractory period

the period during repolarization in which (for 0.5 msec) the membrane cannot be depolarized again

1. polarized

2. depolarized

3. repolarized

4. hyperpolarized

5. Sodium-Potassium pump

what are the five steps to the action potential?

Sodium-Potassium pump

The active transport that returns the sodium ot the inside and potassium to the outside

3, 2

the sodium potassium pump takes out __ Na+ ions, and intakes __ K+ ions

hyperpolarization

happens after repolarization, where the membrane potential becomes more negative because of all the potassium leaving

dysarthria

a speech disorder arising from paralysis, muscular weakness, and discoordination of speech muscles

dysarthria

which problem is a muscle problem or a problem with the nerve going to the muscle?

flaccid dysarthria

muscular weakness and hypertonia arising from LMN damage (CN and speech muscles)

LMN

what is damaged with flaccid dysarthria?

UMN

what is damaged with spastic dysarthria?

spastic dysarthria

an inability to execute skilled movements and muscle weakness brought about by bilateral damage to the UMN of the pyramidal and extrapyramidal pathways

limp muscles and fasciculations

what is flaccid dysarthra associated with?

weak muscles, hypertonia, hyperreflexia

what is spastic dysarthria associated with?

hyperkinetic dysarthria

extraneous involuntary movement of speech muscles in addition to voluntary movement

basal ganglia

what does hyperkinetic dysarthria result from lesion to?

substantia nigra

what does hypokinetic dysarthria result from lesion to?

hypokinetic dysarthria

lack of movement often caused by Parkinson's. Speech will be rusehd with reduced duration and intenstiy.

apraxia

a deficit in the motor programming of articulatory movements in the absence of muscle weakness or paralysis

pre-motor cortex

where does apraxia result from a lesion to?

sound patterning, prosody, motor speech, programming problems

what does apraxia result in issues regarding?

apraxia

what diosrder might one have that results in saying "mamps" for "stamps"

aphasia

language problem resulting in difficulty with word finding, syntax, and comprehension

broca's aphasia

difficulty wiht syntax, good content words

wernicke's aphasia

difficulty with producing speech that actually makes sense and understanding langauge, but good syntax and flow