Comparison of Single-Task versus Dual-Task for Listening Effort

BACKGROUND AND OBJECTIVES: Depending on the kind of task and/or material, listeners sometimes need to pay attention to understand communication. The present study aimed to estimate a listener’s amount of effort needed to understand communication by using recognition score and response time as a function of signal-to-noise ratio (SNR) and to confirm his/ her task dependency for listening effort. SUBJECTS AND METHODS: Forty-eight young adults with normal hearing participated in the study. As stimuli, Korean Speech Perception in Noise test without a question tag and three consecutive digits were used for sentence recognition (or single-task) and arithmetic (or dual-task), respectively. Both tasks were measured in quiet and under four SNR (i.e., 0, -4, -8, -12 dB) conditions. Their outcomes were analyzed and compared in terms of percent correct and response time. RESULTS: Sentence recognition scores and arithmetic scores decreased as the level of noise increased. Response time for sentence recognition decreased as noise increased, whereas the response time for arithmetic increased as noise increased. In addition, there was a negative correlation between error percent and response time in the sentence recognition. Conversely, a positive correlation between error percent and response time appeared in the arithmetic test. CONCLUSIONS: Listening effort showed a different pattern based on the kind of task, single vs. dual, while the dual-task required greater effort from the listener.

The Impacts of Lip-Reading Information on Hearing Impaired Patients’ Sentence Recognition / 听力学及言语疾病杂志

Objective This experiment was to analyze the impacts of lip -reading information on hearing im-paired subjects'sentence recognition got in noisy environment in comparing with the results obtained from the listen-ing and audio -visual testing ways .Methods Fourteen moderate hearing impaired subjects with 55 .4 ± 9 .1 years old were postlingual deafness .Their sentence recognition ability were tested in noisy environments with speech and audio-visual information separately (speech intensity :30 dB SL ,SNR:5 dB) .Results Compared with the sentence recognition administered in the speech information condition 73 .79% ± 7 .95% ,the subjects sentence recognition un-der the audio -visual condition was 86 .57% ± 5 .42% ,which was significantly different (P<0 .05) .Conclusion In noisy environment ,lip-reading can improve hearing impaired patients’ sentence recognition obviously .