Filtered Speech Recognition: A Case Study

Filtering of the speech signal is one way to increase the difficulty of the perceptual task. Filtered speech has the ability to decrease the redundancy of the speech signal and increase the sensitivity to the brain lesion. The listener’s performance will be significantly worse on a filtered Speech recognition task than on an unfiltered speech recognition task because the CANS would be incapable of compensating for the missing information with a breakdown of redundancy of the CANS (lesion). The filtered speech recognition task is able to separate patients with an abnormal CANS from normal functioning CANS. Filtered of speech at various frequencies adversely affect speech perception. Filtered speech helps to understand the contribution of different
Prior to administering any behavioural tests, a baseline audiometric assessment must be conducted to rule out any existing peripheral hearing loss, which can confound test results (Bellis, 2002). 15 Behavioural central auditory tests should include both verbal and non-verbal stimuli, be age-appropriate, and last for an amount of time appropriate for the individual’s motivation and attention span (Bamiou et al., 2001). Due to the heterogeneous nature of APD coupled with the complexity of the CAP no gold standard test for APD exists (Medwetsky, 2002; Musiek, et al., 2005). A typical APD test battery comprises the following sub-tests which are designed to tap into the following four different auditory
Ease of perception is possible due to the redundancy of the speech signal at both acoustic and linguistic levels (Cooper et.al 1952; Liberman1970). Recognizing speech in adverse listening conditions is a significant cognitive, perceptual, and linguistic challenge. Numerous factors have been suggested to explain the difficulties experienced by children when listening to speech in presence of background noise. One such important interaction is between the listener’s age and the noise and reverberation in the environment (Jenstad & Souza, 2007). Interactions among the talker, listener, and listening environment are the main factors affecting success of speech communication. Cognitive factors, including memory, attention, and fatigue may affect perception during difficult listening tasks (Hnath- Chisolm et, al 1998; Oh et, al.2001; Wightman et.al