Auditory cortical processing in cochlear-implanted children with different language outcomes.

PURPOSE: Behavioral evaluation of language development is an important index for the usefulness of cochlear implantation. However, it could not apply to infants and very young children. It is useful to adopt an objective measure to examine speech discrimination in this population. Thus, the current study aimed to predict the different behavioral language performance (good versus poor) in cochlear implant (CI) recipients through the auditory cortical assessment of speech discrimination with mismatch negativity (MMN). METHODS: The study comprised 40 CI children who were divided into two groups according to their behavioral language evaluation outcomes: 20 good and 20 poor CI performers. They were age, gender, and socioeconomically matched. The MMN was examined and compared between both groups with finding out the relationship between MMN and different variables. RESULTS: MMN existed in all good performers and 87.5% of the poor performers. There were significantly shorter latency, larger amplitude, and a larger area of MMN in the good performers. The MMN results correlated with a significant predictive effect on the behavioral measures of language evaluation. CONCLUSION: The MMN is a clinically applicable objective measure of speech discrimination proficiency. Hence, it could be useful in CI programming and auditory cortical monitoring during rehabilitation.

Temporal Resolution in School-Age Children with Cochlear Dead Regions.

BACKGROUND: Sensorineural hearing loss (SNHL) has serious implications on temporal resolution when the nonfunctioning areas known as cochlear dead regions (DRs) exist. Previous studies have not clarified this effect in the pediatric population. PURPOSE: This study aimed to assess the prevalence of DRs in school-age Egyptian children with SNHL and to explore the effect of these DRs on temporal resolution ability. RESEARCH DESIGN: This was a cross-sectional case-control study. STUDY SAMPLE: The Gaps-In-Noise (GIN) test was administered to 70 normal-hearing and 30 hearing-impaired (HI) children (ages 6-16 years), matched in age and gender. In HI children, cochlear DRs were detected using the Threshold-Equalizing Noise test. DATA COLLECTION AND ANALYSIS: Comparison of quantitative data involved parametric (Student's t and one-way ANOVA) and nonparametric (Mann-Whitney U and Kruskal-Wallis H) tests, depending on normality distribution. Comparison of categorical variables required Chi-square or Fisher's exact tests. RESULTS: The prevalence of DRs was 30% in school-age children, with a hearing threshold range of >40-70 dB HL, mainly affecting high frequencies. HI children had significantly impaired GIN test results, especially when DRs were present. CONCLUSIONS: DRs markedly affect temporal resolution. Studying this relationship in children can improve strategies for amplification and temporal processing remediation, enhancing speech perception in these young participants.

Cervical Vestibular-Evoked Myogenic Potentials in Sedated Toddlers.

Introduction Cervical vestibular-evoked myogenic potentials (cVEMPs) are difficult to test in toddlers who cannot follow instructions or stay calm. Objective Due to the growing need for vestibular testing in very young children as a part of a delayed walking assessment battery, this study aimed to provide a solution to this problem by recording the cVEMPs in toddlers during sedation. Method The cVEMPs measures were assessed in 30 toddlers aged 12 to 36 months with normal motor milestones. They were sedated with chloral hydrate. Then, the head was retracted ∼ 30° backward with a pillow under the shoulders, and turned 45° contralateral to the side of stimulation to put the sternocleidomastoid (SCM) muscle in a state of tension. Results The P13 and N23 waves of the cVEMPs were recordable in all sedated toddlers. The cVEMPs measures resulted in the following: P13 latency of 17.5 ± 1.41 milliseconds, N23 latency of 25.58 ± 2.02 milliseconds, and peak-to-peak amplitude of 15.39 ± 3.45 µV. One-sample t -test revealed statistically significant longer latencies and smaller amplitude of the toddlers' cVEMPs relative to the normative data for adults. Conclusions The difficulty of cVEMPs testing in toddlers can be overcome by sedating them and attaining a position that contracts the SCM muscle. However, the toddlers' recordings revealed delayed latencies and smaller amplitudes than those of adults.

Cervical Vestibular-Evoked Myogenic Potentials in Sedated Toddlers

Abstract Introduction Cervical vestibular-evoked myogenic potentials (cVEMPs) are difficult to test in toddlers who cannot follow instructions or stay calm. Objective Due to the growing need for vestibular testing in very young children as a part of a delayed walking assessment battery, this study aimed to provide a solution to this problem by recording the cVEMPs in toddlers during sedation. Method The cVEMPs measures were assessed in 30 toddlers aged 12 to 36 months with normal motormilestones. They were sedated with chloral hydrate. Then, the head was retracted ~ 30° backward with a pillow under the shoulders, and turned 45° contralateral to the side of stimulation to put the sternocleidomastoid (SCM)muscle in a state of tension. Results The P13 and N23 waves of the cVEMPs were recordable in all sedated toddlers. The cVEMPs measures resulted in the following: P13 latency of 17.5 ± 1.41 milliseconds, N23 latency of 25.58 ± 2.02 milliseconds, and peak-topeak amplitude of 15.39 ± 3.45 μV. One-sample t-test revealed statistically significant longer latencies and smaller amplitude of the toddlers' cVEMPs relative to the normative data for adults. Conclusions The difficulty of cVEMPs testing in toddlers can be overcome by sedating them and attaining a position that contracts the SCM muscle. However, the toddlers' recordings revealed delayed latencies and smaller amplitudes than those of adults.

Psychoacoustic Characteristics of Tinnitus versus Temporal Resolution in Subjects with Normal Hearing Sensitivity

Abstract Introduction Cochlear or neural mechanisms of tinnitus generation may affect auditory temporal resolution in tinnitus patients even with normal audiometry. Thus, studying the correlation between tinnitus characteristics and auditory temporal resolution in subjects with tinnitus may help in proper modification of tinnitus management strategy. Objective This study aims to examine the relationship between the psychoacoustic measures of tinnitus and the auditory temporal resolution in subjects with normal audiometry. Methods Two normal hearing groups with ages ranging from 20 to 45 years were involved: control group of 15 adults (30 ears) without tinnitus and study group of 15 adults (24 ears) with tinnitus. Subjective scaling of annoyance and sleep disturbance caused by tinnitus, basic audiological evaluation, tinnitus psychoacoustic measures and Gaps in Noise test were performed. Data from both groups were compared using independent sample t-test. Psychoacoustic measures of tinnitus and Gaps in Noise test parameters of the tinnitus group were correlated with Pearson's correlation coefficient. Results Significantly higher hearing threshold, higher approximate threshold and lower correct Gaps in Noise scores were observed in tinnitus ears. There was no significant correlation between psychoacoustic measures of tinnitus and Gaps in Noise test parameters of the tinnitus group. Conclusion Auditory temporal resolution impairment was found in tinnitus patients, which could be attributed to cochlear impairment or altered neural firing within the auditory pathway. It is recommended to include temporal resolution testing in the tinnitus evaluation battery to provide a proper management planning.

Psychoacoustic Characteristics of Tinnitus versus Temporal Resolution in Subjects with Normal Hearing Sensitivity.

Introduction Cochlear or neural mechanisms of tinnitus generation may affect auditory temporal resolution in tinnitus patients even with normal audiometry. Thus, studying the correlation between tinnitus characteristics and auditory temporal resolution in subjects with tinnitus may help in proper modification of tinnitus management strategy. Objective This study aims to examine the relationship between the psychoacoustic measures of tinnitus and the auditory temporal resolution in subjects with normal audiometry. Methods Two normal hearing groups with ages ranging from 20 to 45 years were involved: control group of 15 adults (30 ears) without tinnitus and study group of 15 adults (24 ears) with tinnitus. Subjective scaling of annoyance and sleep disturbance caused by tinnitus, basic audiological evaluation, tinnitus psychoacoustic measures and Gaps in Noise test were performed. Data from both groups were compared using independent sample t-test. Psychoacoustic measures of tinnitus and Gaps in Noise test parameters of the tinnitus group were correlated with Pearson's correlation coefficient. Results Significantly higher hearing threshold, higher approximate threshold and lower correct Gaps in Noise scores were observed in tinnitus ears. There was no significant correlation between psychoacoustic measures of tinnitus and Gaps in Noise test parameters of the tinnitus group. Conclusion Auditory temporal resolution impairment was found in tinnitus patients, which could be attributed to cochlear impairment or altered neural firing within the auditory pathway. It is recommended to include temporal resolution testing in the tinnitus evaluation battery to provide a proper management planning.

Brainstem Encoding of Aided Speech in Hearing Aid Users with Cochlear Dead Region(s)

Abstract Introduction Neural encoding of speech begins with the analysis of the signal as a whole broken down into its sinusoidal components in the cochlea, which has to be conserved up to the higher auditory centers. Some of these components target the dead regions of the cochlea causing little or no excitation. Measuring aided speechevoked auditory brainstem response elicited by speech stimuli with different spectral maxima can give insight into the brainstem encoding of aided speech with spectral maxima at these dead regions. Objective This research aims to study the impact of dead regions of the cochlea on speech processing at the brainstem level after a long period of hearing aid use. Methods This study comprised 30 ears without dead regions and 46 ears with dead regions at low, mid, or high frequencies. For all ears, we measured the aided speechevoked auditory brainstem response using speech stimuli of low,mid, and high spectral maxima. Results Aided speech-evoked auditory brainstem response was producible in all subjects. Responses evoked by stimuli with spectral maxima at dead regions had longer latencies and smaller amplitudes when compared with the control group or the responses of other stimuli. Conclusion The presence of cochlear dead regions affects brainstem encoding of speech with spectral maxima perpendicular to these regions. Brainstem neuroplasticity and the extrinsic redundancy of speech can minimize the impact of dead regions in chronic hearing aid users.

Brainstem Encoding of Aided Speech in Hearing Aid Users with Cochlear Dead Region(s).

INTRODUCTION: Neural encoding of speech begins with the analysis of the signal as a whole broken down into its sinusoidal components in the cochlea, which has to be conserved up to the higher auditory centers. Some of these components target the dead regions of the cochlea causing little or no excitation. Measuring aided speech-evoked auditory brainstem response elicited by speech stimuli with different spectral maxima can give insight into the brainstem encoding of aided speech with spectral maxima at these dead regions. OBJECTIVE: This research aims to study the impact of dead regions of the cochlea on speech processing at the brainstem level after a long period of hearing aid use. METHODS: This study comprised 30 ears without dead regions and 46 ears with dead regions at low, mid, or high frequencies. For all ears, we measured the aided speech-evoked auditory brainstem response using speech stimuli of low, mid, and high spectral maxima. RESULTS: Aided speech-evoked auditory brainstem response was producible in all subjects. Responses evoked by stimuli with spectral maxima at dead regions had longer latencies and smaller amplitudes when compared with the control group or the responses of other stimuli. CONCLUSION: The presence of cochlear dead regions affects brainstem encoding of speech with spectral maxima perpendicular to these regions. Brainstem neuroplasticity and the extrinsic redundancy of speech can minimize the impact of dead regions in chronic hearing aid users.

Auditory training program for Arabic-speaking children with auditory figure-ground deficits.

OBJECTIVE: Listening to speech in noise makes up a great challenge for school children with auditory processing disorders mainly those with deficit in auditory figure ground (AFG) ability. These children are candidates for auditory training programs targeting AFG such as noise-desensitization programs. This work aimed to develop a new training material in Arabic language targeting this ability. METHODS: A noise-desensitization semi-formal training program was developed and standardized on normal children in a pilot study preceding the main one. Seventeen school children with AFG deficit were submitted to the program for eight weeks then reevaluated. RESULTS: The paired sample t-test revealed significant improvement of all trained children after training period in their psychophysical and electrophysiological results. The electrophysiological threshold of signal to noise ratio decreased from -5.3dB to -11.3dB after training. CONCLUSION: The newly developed training material revealed efficacy in managing children with AFG deficit. The other affected auditory abilities improved also because of the multi-ability tapping character of the program.