Table 3.

Summary of studies of temporal integration in listeners with hearing impairment. The major studies reviewed in the paper are listed in the first column in the order in which they are discussed in Section II-C. The second column gives the stimuli used. The third column (Thresh. Match?) provides information concerning the use of threshold matching to simulate hearing loss (with the noise-masking threshold-elevation procedure abbreviated as NM). The fourth column gives the number (No.) of subjects (Ss) and either the range or the mean (X̄) of ages in years of the NH and HI groups. The fifth column provides the stimulus durations that were tested. The final column summarizes key comparisons of NH and HI performance.

Study	Stimulus	Thresh. Match?	No. and Ages (Years) of Ss	Stimulus Durations	Summary of Findings
Gengel (1972)	Pure tones: 0.5, 2.0, and 4.0 kHz	NM	Unknown	10, 20, 50, 200, and 500 msec	Temporal integration averaged 15 dB at 0.5 kHz, 10 dB at 2.0 kHz, and 8.5 dB at 4.0 kHz in NM NH listeners, similar to that obtained in NH listeners in quiet and larger than amount observed in HI listeners with similar degree of threshold shift
Fastl (1977)	Pure tones: 1.0, 2.5., 3.0, 3.5, and 7.0 kHz	NM	Unknown	3, 10, 30, 100, and 300 msec	Temporal integration in NM NH listener was roughly 25 dB at all frequencies tested. HI listener had notched loss at 3.0 kHz, where temporal integration was 0.0 dB.
Florentine et al. (1988)	Pure tones: 0.25, 1.0, and 4.0 kHz	NM	5NH: 20-42 6HI: 20-62	2, 4, 8, 16, 32, 64, 128, 256, and 512 msec	Temporal integration in NH listeners and NM NH listeners was similar: 12 dB at 0.25 kHz, 15 dB at 1.0 kHz, and 18 dB at 4.0 kHz. Reduced temporal integration observed in HI listeners at frequencies in region of hearing loss
Oxenham et al. (1997)	Pure tone of 6.5 kHz in background of bandpass noise	NM	4 NH: 25-34 4 HI: 61-81	9 values between 2 and 200 msec	Slope of temporal-integration function steeper from 2-20 msec than from 20-200 msec in all listeners. Less temporal integration for HI listeners in noise compared to NH listeners in noise.