Late Latency Potentials

Question 1

What stimulus can you use for LLPs

Answer 1

Tones, clicks and speech stimulus

Question 2

How much time do you need to capture LLPs

Answer 2

Longer time window for LLPs

Question 3

What is an exogenic potential (3)

Answer 3

1. Potentials that are influenced by the stimulus characteristcs
2. They don’t use cognitive processing
3. Tests include ABR, ECochG and MMN

Question 4

What is an endogenic (4)

Answer 4

1. Requires cognitive processing (depends on the listeners attention)
2. Affected by sleep
3. Tests include ALLR and MMN
4. Event related potentials

Question 5

What are the different potentials (4)

Answer 5

1. N1 (100)
2. P2 (160)
3. N2 (230)
4. P3 (300) P3a and P3b

Question 6

What is an event related potential (2)

Answer 6

1. Are potentials generated from brain processing information
2. ERP are elicited by oddball or rarely occurring stimulus (e.g. P300)

Question 7

What is an oddball

Answer 7

Out of 100 stimulus, at least 15 will occur randomly

Question 8

What is P3 and when does it occur (3)

Answer 8

1. > 300 has two peaks
2. (Pa) is earlier and smaller, represents sound discrimination (me, ma)
3. (Pb) is larger and later, represents sound recognition (dog, cream)

Question 9

What is the MMN equation

Answer 9

Difference wave = deviant wave-standard wave

difference wave is the remaining MMN

Question 10

What is N1 and when does it occur

Answer 10

(100) 59-139 ms

Question 11

What is P2 and when does it occur

Answer 11

(160) 125-208 ms

Question 12

What is N2 and when does it occur

Answer 12

(230) 208-300 ms

Question 13

What kind of potential is a P300

Answer 13

It is an event related potential

Question 14

What kind of potential is a MMN

Answer 14

An event related potential it is an automatic pre-attentive response to stimulus change

Question 15

What impacts on LLR (2)

Answer 15

1. Age

2. State of arousal

Question 16

What is the age effect in LLR’s (3)

Answer 16

1. 5-6 year olds have a distinctive peak at P1
2. N1 and P2 improve with age
3. Potentials reach full maturity in teenage years

Question 17

What do ALLR’s assess (3)

Answer 17

1. They provide evidence of audible stimuli at the auditory cortex
2. Estimates hearing sensitivity
3. Determines site of lesions (retrocochlear and CAPD)

Question 18

What causes small ALLR waves

Answer 18

Waves can be smaller because of SNHL or conductive loss, because fewer waves travel beyond the cochlear

Question 19

What does N400 test (2)

Answer 19

1. the perception of incongruity (I’ll take coffee with cream and dog)
2. Frontal Cortex

Question 20

What are the P300 site generators (4)

Answer 20

1. Frontal cortex
2. Centropatietal cortex
3. Auditory cortex
4. Sub-cortical sites

Question 21

What do P300 abnormalities indicate (5)

Answer 21

1. Attention disorders
2. Autism
3. Reading disability
4. APD
5. Downs syndrome