Auditive identification of signal-processed environmental sounds: Monitoring the environment

Abstract

The goal of the present study was to compare six transposing signal-processing algorithms based on different principles (Fourier-based and modulation based), and to choose the algorithm that best enables identification of environmental sounds, i.e. improves the ability to monitor events in the surroundings. Ten children (12-15 years) and 10 adults (21-33 years) with normal hearing listened to 45 representative environmental (events) sounds processed using the six algorithms, and identified them in three different listening experiments involving an increasing degree of experience. The sounds were selected based on their importance for normal hearing and deaf-blind subjects. Results showed that the algorithm based on transposition of 1/3 octaves (fixed frequencies) with large bandwidth was better (p<0.015) than algorithms based on modulation. There was also a significant effect of experience (p<0.001). Adults were significantly (p<0.05) better than children for two algorithms. No clear gender difference was observed. It is concluded that the algorithm based on transposition with large bandwidth and fixed frequencies is the most promising for development of hearing aids to monitor environmental sounds.

Vibrotactile identification of signal-processed sounds from environmental events

“…The test sounds used in the present experiment were the same 45 environmental sounds ( Table 1) used in previous experiments by Ranjbar et al [31]. The sounds were selected by people with both normal hearing and dual sensory impairment who classified the events causing the sounds as the most important to be informed about (described in more detail in Borg et al [1] and Ranjbar et al [31]).…”

“…The sounds were selected by people with both normal hearing and dual sensory impairment who classified the events causing the sounds as the most important to be informed about (described in more detail in Borg et al [1] and Ranjbar et al [31]). …”

“…In a previous study, six algorithms developed on the basis of two principles (transposition and modulation) were used to process environmental sounds and tested using the hearing sense [31]. In the present study, the six basic algorithms (three transposing and three modulating) from the previous study (with some modifications) and seven additional algorithms were used to process the same environmental sounds and tested using the vibratory sense.…”

Signal Processing Methods for Improvement of Environmental Perception of Persons with Deafblindness

“…These sounds were chosen as representative and important sounds to be informed about, by a panel of 11 persons with normal hearing and vision in addition to some persons with DB [9]. These sounds have been used as stimuli also in previous studies [9][10][11].…”

“…These algorithms were tested by Ps with D and/ or normal hearing in previous laboratory studies [1] and selected as good candidates to be implemented in a vibratory aid for improvement of environmental perception. For more detailed descriptions of the algorithms see the studies [1,9,10].…”