Effects of age and frequency disparity on gap discrimination

Abstract

Temporal discrimination was measured using a gap discrimination paradigm for three groups of listeners with normal hearing: (1) ages 18-30, (2) ages 40-52, and (3) ages 62-74 years. Normal hearing was defined as pure-tone thresholds < or = 25 dB HL from 250 to 6000 Hz and < or = 30 dB HL at 8000 Hz. Silent gaps were placed between 1/4-octave bands of noise centered at one of six frequencies. The noise band markers were paired so that the center frequency of the leading marker was fixed at 2000 Hz, and the center frequency of the trailing marker varied randomly across experimental runs. Gap duration discrimination was significantly poorer for older listeners than for young and middle-aged listeners, and the performance of the young and middle-aged listeners did not differ significantly. Age group differences were more apparent for the more frequency-disparate stimuli (2000-Hz leading marker followed by a 500-Hz trailing marker) than for the fixed-frequency stimuli (2000-Hz lead and 2000-Hz trail). The gap duration difference limens of the older listeners increased more rapidly with frequency disparity than those of the other listeners. Because age effects were more apparent for the more frequency-disparate conditions, and gap discrimination was not affected by differences in hearing sensitivity among listeners, it is suggested that gap discrimination depends upon temporal mechanisms that deteriorate with age and stimulus complexity but are unaffected by hearing loss.

Cortical Evoked Response to Gaps in Noise: Within-Channel and Across-Channel Conditions

“…Most interesting in light of the present results are the behavioral findings for older adults. This group often has poorer within-and across-channel gap detections than young adults; yet, age-group differences are much larger for acrosschannel than within-channel conditions (e.g., Lister & Roberts, 2005;Lister, et al, 2002).As within-and across-channel performance was not correlated in the present study (r = 0.22, p = 0.50) or others (Phillips & Smith, 2004), it is likely that different mechanisms are involved in the two tasks. The present study represents a first step in the investigation of the physiological underpinnings of across-channel gap detection.…”

“…The shortest gap that a listener can detect (relative to the standard) is called a gap detection threshold (GDT). Psychophysical GDTs are influenced by a number of stimulus factors, including marker bandwidth (Eddins, Hall, & Grose, 1992;Snell, Ison, & Frisina, 1994), marker duration (He, Horwitz, Dubno, & Mills, 1999), monotic, diotic, or dichotic presentation modes (Gordon-Salant & Fitzgibbons, 1999;He, et al, 1999;Lister & Roberts, 2005), and the spectral similarity of the markers before and after the gap (Lister, Besing & Koehnke, 2002;Oxenham, 2000).…”

“…The shortest gap that a listener can detect (relative to the standard) is called a gap detection threshold (GDT). Psychophysical GDTs are influenced by a number of stimulus factors, including marker bandwidth (Eddins, Hall, & Grose, 1992;Snell, Ison, & Frisina, 1994), marker duration (He, Horwitz, Dubno, & Mills, 1999), monotic, diotic, or dichotic presentation modes (Gordon-Salant & Fitzgibbons, 1999;He, et al, 1999;Lister & Roberts, 2005), and the spectral similarity of the markers before and after the gap (Lister, Besing & Koehnke, 2002;Oxenham, 2000).Behavioral studies have shown that, when the stimuli that mark the silent gap are noise bands of similar frequency, known as within-channel gap detection, the task is relatively easy and GDTs are small (Lister & Roberts, 2005;Lister, et al, 2002). When the noise bands that mark the gap are of different frequencies, known as across-channel gap detection, the task is more difficult and GDTs are larger (Lister & Roberts, 2005;Lister, et al, 2002).…”

Perception of Across-Frequency Asynchrony by Listeners with Cochlear Hearing Loss

“…However, the HI listeners in this study were on average older than the NH listeners in the study by Wojtczak et al (2012) used as a control group. A large number of studies have reported clear effects of age on gap detection and gap-duration discrimination for both within-channel and across-channel markers (Fitzgibbons and Gordon-Salant 1994;Schneider et al 1994;He et al 1999;Lister et al 2000Lister et al , 2002Lister and Roberts 2005). Since the NH and HI listeners compared in this study were not age-matched, some of the observed differences between their data may reflect poorer coding of temporal information or a reduced ability to integrate temporal information across frequency due to the age of the HI listeners.…”

“…However, deficits due to cochlear hearing loss have been shown in tasks involving comparisons of temporal information across frequency, although not consistently. Across-channel gap detection and gap-duration discrimination measured with frequency-disparate markers preceding and following silent gaps have been shown to be unaffected by hearing loss (Lister et al 2002;Lister and Roberts 2005). Similarly, the ability to detect a difference in temporal envelope patterns in the presence of an interfering modulation in the remote frequency region is comparable for the NH and HI listeners (Grose and Hall, 1996).…”