In the word recognition score, we choose an intensity level (that is above the SRT so it is audible to lsitener) and the score is simply the % of words that they got right at that level.
In speech recognition, we increase and decrease the intensity level while testing. Using the psychometric function, we find the threshold in dB HL where they perform at 50%.
WRT = set the level, maintain. SRT= set level and based on response, inc or dec