artic measurement 1

Question 1

describe the process of articulation (6)

Answer 1

1. nerve activation
2. muscle contraction
3. oral movement/constrictions
4. airflow and resonance
5. speech acoustics

Question 2

what kind of symptom is observed for upper vs lower motor neuron damage?

Answer 2

• upper: hypertonia
• lower: hypotonia

Question 3

what consists of the motor unit? (3)

Answer 3

• motor neuron + its axon
• corresponding motor end plate
• all innervated muscle fibers

Question 4

what does electromyography (EMG) track? (2)

Answer 4

• single motor unit activity (can be summed of many units)
• spikes at specific frequency when muscle fiber is activated

Question 5

why are needle electrodes less suitable for speech research? (4)

Answer 5

• rigid
• large
• restrict movements
• easily displaced by movements

Question 6

describe EMG signal processing (4)

Answer 6

• 3 electrodes (2 on muscle, 1 reference)
• differential amplifier measures voltage diffs and subtracts from reference
• rectification
• filtering

Question 7

T or F: more signal smoothing (or increasing time window) = less detail

Answer 7

true

Question 8

how do you get a clearer signal? (2)

Answer 8

1. average EMG data over multiple repetitions (like ABR)
2. use filters (e.g., band pass)

Question 9

T or F: you can see single motor units firing with surface EMGs

Answer 9

false (and you typically don’t need to see single unit level firing for studying speech)

Question 10

T or F: individuals who stutter = slower buildup of EMG activity

Answer 10

true

Question 11

which words in sentences have higher EMG for stutterers?

Answer 11

words in sentence initial position

Question 12

what is a strain gauge system? what are its cons?

Answer 12

• bending metal strips changes electrical resistance
• cons: cannot measure tongue movements, head needs to be restrained

Question 13

what is an x-ray microbeam system? what are its cons?

Answer 13

• uses narrow beam of x-rays (safer) to localize + track the 2D movements of small gold pellets attached to select speech structures
• cons: only 2 in the world

Question 14

what is electromagnetic articulography (EMA)?

Answer 14

• uses variable magnetic fields that tracks movement of points inside and outside oral cavity
• depending on distance of receiver coil from each transmitter coil, the induced current will have different frequency components

Question 15

pros and cons of EMA?

Answer 15

• pros: high sampling rate, high accuracy
• cons: complicated, time-consuming, requires participant cooperation, coding

Question 16

the body prefers to drop amplitude and make things go faster (more economic). what happens in the case of people who stutter or have apraxia?

Answer 16

keep the bigger amplitude + try to go faster (physiologically taxing)

Question 17

what is feedback perturbation? (2)

Answer 17

• masking noise + masseter tendon vibration
• big movements = poor control

Question 18

what is cSTI? (2)

Answer 18

• cyclic spatial temporal index
• low numbers = consistent speech movements

Question 19

what is cross spectral analysis and continuous relative phase? (2)

Answer 19

• measures phase relationships between articulators
• phase errors = speech sound errors