Decision strategies in loudness judgments of time-varying sounds inferred from two psychophysical tasks
Wednesday 3 june, 2015, 14:00 - 14:20
0.2 Berlin (90)
Psychophysical reverse-correlation has been shown to provide a unique framework for identifying decision strategies underlying various perceptual evaluations. Over the last few years, this method has been employed to examine specifically temporal weighting of loudness for time-varying sounds. Primacy and recency effects were observed, indicating that level-variations occurring at the beginning or at the end of non-stationary sounds have a stronger impact on their global loudness than others, a finding incompatible with the uniform temporal weighting used in current indicators of loudness such as L<sub>Aeq</sub> or N<sub>5</sub>. However, such effects have been exclusively observed in discrimination tasks. In this study, the temporal weighting of loudness was measured and compared with the same group of subjects participating in (i) level-discrimination tasks and in (ii) magnitude estimation (ME) tasks. Stimuli were 3-s white noises consisting of 250-ms segments randomly varying in level. The weights attributed to the 12 temporal portions of these sounds were inferred from subjects 'responses using either multiple (i) logistic or (ii) linear regressions. Small but significant primacy and recency effects were observed in the level-discrimination task, whereas only primacy effects were found in the ME task, suggesting that different temporal weighting strategies were involved in these two tasks.
ICS file for iCal / Outlook