2AFC AM Detection
Time
Warning
Interval 1
Interval 2
Respond: 1 or 2?
Trial 1
1
Warning
Interval 1
Interval 2
Respond: 1 or 2?
Trial 2
2
Warning
Interval 1
Interval 2
Respond: 1 or 2?
Trial 3
2
Feedback
AM
Not AM
Which one was AM?
Vary depth of AM to find a threshold
The task in AM detection is illustrated here. The listener gets a warning followed by two interval indicators. During one interval, randomly chosen, an AM sound is presented; in the other interval the same sound but unmodulated is presented. The listener chooses the interval containing the AM sound and receives feedback. The modulation depth is varied to find the threshold for AM detection, the amount of modulation required to hear the modulation some proportion of the time.