BACKGROUND AND OBJECTIVES: Numerous studies have indicated deterioration of speech perception in noisy conditions among the elderly even those with normal hearing capabilities. The aim of this study was to investigate the effects of age on the speech-in-noise identification by speech-in-noise (SIN) test, subjective ratings of hearing difficulties by speech, spatial, and qualities of hearing scale (SSQ) questionnaire and encoding of fundamental frequency (F0) by Speech auditory brainstem response (ABR) in the elderly and comparing the results with young people. SUBJECTS AND METHODS: The present study was conducted on 32 elderly people aged over 60 years old (17 male and 15 female) with the mean age of 68.9 (standard deviation=6.33) possessing normal peripheral hearing and 32 young subjects (16 male and 16 female) aged 18-25 years old. RESULTS: Findings showed that the score of SIN test is lower among the elderly people as compared with young people in signal-to-noise ratios of 0 and -10 based on Iranian version of SSQ questionnaire (p < 0.001). The range of F0 amplitude in the elderly people is also lower than young people (p < 0.001) in Speech ABR. CONCLUSIONS: It seems that speech processing in older people is deteriorated comparing with young people regardless of their normal peripheral auditory thresholds. This decrease will result in weaker perception and improper segregation of speech from other competing sources.
Adult ; Aged ; Aging ; Auditory Threshold ; Evoked Potentials, Auditory, Brain Stem ; Hearing ; Humans ; Male ; Signal-To-Noise Ratio ; Speech Perception

BACKGROUND AND OBJECTIVES: The aim of this study was to evaluate the usefulness of speech mapping based on real ear measurement for routine hearing aid fitting and to compare functional gains for evaluating subjective satisfaction of hearing aid users. SUBJECTS AND METHOD: Twenty two participants with bilateral symmetric (< 10 dB HL difference) sensorineural hearing loss were enrolled in this study. All participants were fitted unilateral hearing aids with speech mapping using the National Acoustic Laboratories-Nonlinear 2 formula. After the initial fitting, patients were followed with the 2nd and 3rd fitting at two weeks and six weeks, respectively, and measured for aided pure tone average (PTA), aided speech discrimination score (SDS), the difference between target gain and real ear insertion gain (REIG) using speech mapping and subjective satisfaction via Korean Adaptation of the International Outcome Inventory for Hearing Aids (K-IOI-HA) questionnaire before further fitting was performed. We analyzed correlation of each parameter at 2nd and 3rd fitting with the K-IOI-HA score. RESULTS: Every sequential aided PTA and SDS at 2nd fitting and 3rd fitting were significantly improved after repeated hearing aid fitting (all p < 0.01). In the correlation analysis between K-IOI-HA and each parameter, the aided PTA and aided SDS did not show significant correlations with subjective satisfaction from the 2nd and 3rd fittings. But the difference between the target gain and R EIG in speech mapping showed significant negative correlations with the satisfaction scores at various speech level (r=–0.609 to –0.709, all p < 0.01). CONCLUSION: Speech mapping using real ear measurement was useful to expect subjective satisfaction of hearing aid users and it would be a valuable tool for fine tuning to achieve individual preferences.
Acoustics ; Auditory Threshold ; Ear ; Hearing Aids* ; Hearing Loss ; Hearing Loss, Sensorineural ; Hearing* ; Humans ; Methods ; Speech Perception

BACKGROUND AND OBJECTIVES: Deficits of the aging auditory system negatively affect older listeners in terms of speech communication, resulting in limitations to their social lives. To improve their perceptual skills, the goal of this study was to investigate the effects of time alteration, selective word stress, and varying sentence lengths on the speech perception of older listeners. SUBJECTS AND METHODS: Seventeen older people with normal hearing were tested for seven conditions of different time-altered sentences (i.e., +/-60%, +/-40%, +/-20%, 0%), two conditions of selective word stress (i.e., no-stress and stress), and three different lengths of sentences (i.e., short, medium, and long) at the most comfortable level for individuals in quiet circumstances. RESULTS: As time compression increased, sentence perception scores decreased statistically. Compared to a natural (or no stress) condition, the selectively stressed words significantly improved the perceptual scores of these older listeners. Long sentences yielded the worst scores under all time-altered conditions. Interestingly, there was a noticeable positive effect for the selective word stress at the 20% time compression. CONCLUSIONS: This pattern of results suggests that a combination of time compression and selective word stress is more effective for understanding speech in older listeners than using the time-expanded condition only.
Aging ; Auditory Perception ; Hearing ; Speech Perception*

BACKGROUNDMany factors interfering with a listener attempting to grasp speech in noisy environments. The spatial hearing by which speech and noise can be spatially separated may play a crucial role in speech recognition in the presence of competing noise. This study aimed to assess whether, and to what degree, spatial hearing benefit speech recognition in young normal-hearing participants in both quiet and noisy environments.

METHODSTwenty-eight young participants were tested by Mandarin Hearing In Noise Test (MHINT) in quiet and noisy environments. The assessment method used was characterized by modifications of speech and noise configurations, as well as by changes of speech presentation mode. The benefit of spatial hearing was measured by speech recognition threshold (SRT) variation between speech condition 1 (SC1) and speech condition 2 (SC2).

RESULTSThere was no significant difference found in the SRT between SC1 and SC2 in quiet. SRT in SC1 was about 4.2 dB lower than that in SC2, both in speech-shaped and four-babble noise conditions. SRTs measured in both SC1 and SC2 were lower in the speech-shaped noise condition than in the four-babble noise condition.

CONCLUSIONSpatial hearing in young normal-hearing participants contribute to speech recognition in noisy environments, but provide no benefit to speech recognition in quiet environments, which may be due to the offset of auditory extrinsic redundancy against the lack of spatial hearing.

Adolescent ; Adult ; Auditory Threshold ; physiology ; Female ; Hearing ; physiology ; Humans ; Male ; Noise ; Speech Perception ; physiology ; Speech Reception Threshold Test ; Young Adult

Similar to the visual dual-pathway model, neurophysiological studies in non-human primates have suggested that the dual-pathway model is also applicable for explaining auditory cortical processing, including the ventral "what" pathway for object identification and the dorsal "where" pathway for spatial localization. This review summarizes evidence from human neuroimaging studies supporting the dual-pathway model for auditory cortical processing in humans.
Animals ; Auditory Cortex ; anatomy & histology ; physiology ; Auditory Pathways ; anatomy & histology ; physiology ; Auditory Perception ; physiology ; Humans ; Macaca ; anatomy & histology ; physiology ; Models, Neurological ; Neurons ; physiology ; Pitch Discrimination ; physiology ; Sound Localization ; physiology ; Space Perception ; physiology

OBJECTIVE: To investigate the relationship between minimum contralateral masking level (MCML) and pure tone threshold of the masking ears by the same frequency tone masking test. METHODS: The pure tone thresholds of 30 subjects (60 ears) were measured by pure tone audiometry and MCML was obtained by means of the same frequency tone masking test. RESULTS: When the stimulus was at the threshold of masked ears, the differences between MCML and pure tone threshold of masking ears were among 0-30 dBHL. 82.4 percent of results showed the differences not higher than 10 dBHL, 97.1 percent of results showed the differences not higher than 15 dBHL. When the stimulus was at 10 dBHL above the threshold of masked ears, the differences between MCML and pure tone threshold of masking ears were among 0-35 dBHL. 90.5 percent of results showed the differences not higher than 25 dBHL, 98.1 percent of results showed the differences not higher than 30 dBHL. CONCLUSION The real thresholds can be deduced correctly by the same frequency tone masking test.
Acoustic Stimulation/methods* ; Adult ; Audiometry, Pure-Tone/methods* ; Auditory Perception/physiology* ; Auditory Threshold ; Female ; Forensic Medicine/methods* ; Hearing Tests/methods* ; Humans ; Male ; Perceptual Masking

OBJECTIVE: To seek a convenient and effective method through subjective psychophysical measurements and CAP/SIR assessment. To compare the discrimination of rehabilitation between post-lingual and pre-lingual deafened patients. METHOD: Thirty-one post-lingual cochlear implantees and 59 pre-lingual cochlear implantees, the warble tone and CAP/SIR were assessed. The discrimination of threshold levels, comfortable levels and dynamic range between post-lingual and pre-lingual deafened patients in same electrodes were compared. RESULT: There was no statistic difference in warble tone, T-levels, C-levels and dynamic range in same electrodes implant after 6 months implant (P>0.05). The score of CAP and SIR in post-lingual deafened patients were more prominent. CONCLUSION CAP and SIR is a kind of convenient and effective method to assess the ability of aural and oral. There was no discrimination in warble tone, T-levels, C-levels and dynamic range in same electrodes implant, but the ability of aural and oral in post-lingual deafened patients were more prominent.
Adolescent ; Adult ; Auditory Threshold ; Child ; Child, Preschool ; Cochlear Implantation ; methods ; Cochlear Implants ; Deafness ; etiology ; physiopathology ; therapy ; Humans ; Infant ; Middle Aged ; Speech Perception ; Treatment Outcome ; Young Adult

OBJECTIVE: To analyze the short monosyllabic list of Mandarin speech test materials (MSTMs) which have been evaluated the equivalence of difficulty, and to establish the performance-intensity function (P-I function) for people with normal hearing as clinical reference of hearing recovery and individuals ability to perceive and process speech. METHOD: Thirty-seven subjects (the age ranged from 18 to 26 years old) who speak Mandarin well in their daily lives with normal hearing participated in this study. Eight lists of the Short Mandarin Monosyllabic materials (20 words per list) with equal difficulty were utilized. The results were analyzed by Statistical Package for the Social Sciences (SPSS) software version 17.0. RESULT: P-I function for short monosyllabic word list was x = 98.557/(1 + 12.243 exp (-0.17(P-15, x(max) = 98.557. And the sound pressure level of speech corresponding to a 50% recognition score was 29.6 dB SPL or 9.6 dB HL. The results showed P-I function of 3.1 per dB for Mandarin materials. CONCLUSION The study established the P-I function of the Mandarin short monosyllabic word list materials with equal difficulty, which provides the normative data for identifying the normal hearing in a clinical setting.
Adult ; Auditory Perception ; Female ; Hearing Tests ; methods ; Humans ; Male ; Speech ; Speech Perception ; physiology

In order to explore the possible mechanisms by which ethologically relevant sounds can be extracted from complex auditory environments, this study examined the effects of weak noise on the rate-intensity functions (RIFs) of neurons responding to tone burst in the inferior colliculus (IC) of nine mice (Mus musculus Km). Under free field stimuli conditions, a total of 112 IC neurons were recorded. RIFs with and without simultaneous presentation of weak noise, of which the intensity was relative to 5 dB below minimum threshold of tone burst, were measured in 44 IC neurons. By means of evaluating the changes of dynamic range (DR), slope of RIFs, and percent inhibition at different tone burst intensities evoked by the weak noise, three types of variations in RIFs were observed, i. e., inhibition (39/44, 88.6%), facilitation (2/44, 4.6%), and no effectiveness (3/44, 6.8%). Statistical analysis indicated that only inhibitory effect of weak noise was significant (P< 0.001, n = 39). The inhibitory effect of weak noise was greater at lower stimulus intensity of tone burst but decreased significantly with increased stimulus intensity (P< 0.0001, n = 39). In addition, the DR and slope of RIFs became narrower and steeper with weak noise presentation, respectively (P< 0.01, n = 31). The results from the present study suggest that weak noise exerts a dynamic modulatory action on acoustical intensity sensitivity of IC neurons, which possibly leads to a better understanding of neural mechanisms underlying the extraction of sound signals from natural auditory scenes.
Acoustic Stimulation ; Animals ; Auditory Perception ; physiology ; Auditory Threshold ; physiology ; Inferior Colliculi ; physiology ; Mice ; Neurons ; physiology ; Noise

Auditory Perception ; Child ; Humans ; Sound Localization