Threshold detection of Pulse repetitions and Sounds from Pulse to Tone

Summary: Two studies have been conducted using experiments that let participants try to detect target sounds in pink noise. If they reported to have detected a target signal then next time the energy of the target signal of that condition is decreased by 1dB. If they reported not to have detected a target signal then next time the energy of the target signal of that condition is increased by 1dB. This results in data points around 50% probability of detecting a minimum of 1 target sound in the noise. One study examines the detection thresholds of pulse repetitions with irregular and regular intervals and the other the detection thresholds of target sounds between the pulse-domain and tone-domain. We expected that detection of thresholds in the first study is a statistical process in which the threshold detection value is a function of the number of repetitions and the standard deviation of noise in a Gaussian distribution. Hereby we aim to find the mean and especially the standard deviation. The difference of the mean and standard deviation between irregular and regular pulse intervals is small. The average mean therefore is -3.908 and the average standard deviation is 1.934. Also what has been found is a significant difference of 6 regular pulse repetitions being 0.78 dB lower than 6 irregular pulse repetitions. The second study gives us an indication of a transition point between the pulse-domain and the tone-domain. There has been found an indication of a transition point at a target sound with duration of 0.03 seconds.