TWO FOR ONE : DISCRIMINABILITY FUNCTIONS CAN PRODUCE BOTH MASKING AND FIXED-SIGNAL FUNCTIONS.
Auditory level discrimination tasks require observers to judge which of two stimuli, X or X+Î”X, has the greater level. Four observers participated in a two-alternative forced-choice
task with two 10-ms bursts of 1000-Hz sinusoids of level X and X+Î”X. Sinusoids were presented in quiet. Five discriminability functions were collected, each based on seven values of Î”X. From these functions, masking and fixed-signal functions can be constructed by extracting the relevant information from each of the five discriminability functions. By comparing the masking and fixed-signal functions it should be possible that the units problem in audition can be brought to finality.