Pure tone auditory thresholds can change according to duration of interrupted tones in patients with psychogenic hearing loss

Conclusion: Pure tone auditory thresholds can change according to duration of interrupted tones in patients with mild to severe psychogenic hearing loss (PHL). Objectives: To examine how the duration of stimulus tones affects the hearing thresholds of patients with PHL. Methods: Twelve patients with PHL (21 ears) were enrolled in this study. We initially measured their hearing thresholds using interrupted tones with a duration of 2 s and equal length of on-time and off-time, 225 +/-+/- 35 ms, respectively. After a 10 min interval, we measured their hearing thresholds using the same interrupted tones conditions lasting 5 s. The average threshold gains (2 s thresholds minus 5 s thresholds) were compared to those of 15 control subjects with normal hearing (25 ears), 15 patients with cochlear hearing loss (23 ears), and 4 patients with retrocochlear lesions (4 ears). Patients with profound PHL (4 patients, 6 ears) were analyzed separately. Results: The average threshold gain of PHL patients (excluding profound PHL patients) at all frequencies was 18.3 dB, which was significantly larger than that of other groups: 0.3 dB (profound PHL patients), 3.8 dB (controls with normal hearing), 3.0 dB (patients with cochlear hearing loss), and 3.2 dB (patients with retrocochlear lesions).