Background and Aim: Tinnitus, characterized by the perception of sound without the presence of an external auditory stimulus, can profoundly affect the quality of life. This review study aims to assess the role of attention modulation in tinnitus management and investigate the neurophysiological mechanism of attention and its interaction with emotional processing in patients with tinnitus.
Recent Findings: The studies revealed differences in the function of attentional networks among individuals with tinnitus. The studies showed the positive impact of various techniques for attention modulation through direct attention training or indirect mechanisms influencing attention. These techniques could modify attentional biases, enhance attention control, and alleviate tinnitus-related distress.
Conclusion: The results of studies suggest the potential role of attention modulation in tinnitus management. By targeting attentional processes, researchers and clinicians can provide more effective interventions for individuals with tinnitus. However, there is a need for further investigation to optimize the intervention protocols by collaboration between researchers, clinicians, and individuals with tinnitus to achieve success in tinnitus management.

Background and Aim: Inner ear infection with some viruses may be one of the possible causes of Sensorineural Hearing Loss (SNHL). This study aims to determine the frequency of Herpes Simplex Virus 1 and 2 (HSV-1, HSV-2) and Cytomegalovirus (CMV) in perilymph and peripheral blood samples of cochlear-implanted children.
Methods: In this cross-sectional study, 30 children with severe-to-profound SNHL (aged 1.1–5 years) underwent cochlear implantation surgery. During surgery, their perilymph and peripheral blood samples were collected. The samples were analyzed separately for the presence of herpes HSV-1, HSV-2, and CMV by real-time Polymerase Chain Reaction (PCR) method. The load of IgG and IgM antibodies against these viruses was determined using the Enzyme-Linked Immunosorbent Assay (ELISA) method.
Results: The frequency of CMV in perilymph samples was 16.7% (5 patients) and in peripheral blood samples was 3.3% (1 patient). The IgG antibody against CMV and HSV-1 was positive in 80% and 46.7% of the patients, respectively. The IgM antibody against CMV was positive in 10%. The mean IgM serum antibody load against HSV-1, HSV-2, and CMV was 2.70, 1.70, and 5.47, respectively, and the mean IgG antibody load against these viruses was 56.07, 2.50, and 23.67, respectively.
Conclusion: The IgG test is positive in cochlear-implanted children with CMV in their perilymph samples, and the CMV genome is not present in their peripheral blood. This may indicate the previous presence of this virus in the ear and its role in hearing loss.

Background and Aim: The utilization of speech materials in audiological assessments has faced challenges due to a lack of standardization and insufficient consideration of acoustic factors. This study aimed to develop a set of psychometrically validated monosyllabic and disyllabic words in Persian for use in auditory tests.
Methods: This cross-sectional study involved collecting the most frequently used one- and two-syllable words from Persian dictionaries. A panel of experts evaluated the selected words using a 4-point Likert scale. Based on their recommendations, 382 monosyllabic words and 150 disyllabic words met the established criteria. Male and female talkers recorded these words, which were then presented in a random order to 30 young adults with normal hearing (aged 18–30 years). The presentation intensity levels ranged from 0 to 48 dB HL with 8 dB increments. Logistic regression was used to determine the psychometric properties of the words.
Results: As the intensity level increased, the percentage of word recognition scores also increased, reaching 100% at an intensity level of 48 dB HL. For Persian monosyllabic words, the mean psychometric slope was 0.29 %/dB for male talkers and 0.25 %/dB for female talkers. The corresponding slopes for Persian disyllabic words were 0.23 %/dB and 0.21 %/dB, respectively.
Conclusion: This study successfully developed 382 monosyllabic words and 150 disyllabic words in Persian with comparable psychometric properties. These words can be utilized in auditory tests for Iranian adults.

Background and Aim: Early communication skills in children with hearing loss depend on the quantity and quality of information received from parents. The present study aimed to investigate the effectiveness of early communication skills training in developing the communication skills of infants and toddlers with cochlear implants.
Methods: To this end, 54 infants and toddlers at the age range of 8–24 months with sever to profound hearing loss fitted by Cochlear Implant (CI) with their mothers participated in this study. The experimental and wait list control groups had auditory verbal therapy as the main intervention after the CI; however, the experimental group received a systematic early communication skills program. All subjects were assessed using the Communication and Symbolic Behaviour Scales Developmental Profile as the pre-and post-tests.
Results: Multivariate analysis of covariance indicated the effect of systematic training on the early communication development of subjects in intervention group.
Conclusion: Teaching the parents how to interact with infants and toddlers with CI could improve the communication skills of the infants and therefore it’s recommended to be included in the auditory rehabilitation programs.

Background and Aim: It is important to know how much are the auditory electrophysiological tests affected by sleep and wakefulness to be employed in different situations. This problem is more important for the speech-evoked Auditory Brainstem Response (speech-ABR) test that is affected by higher-level processing. This study aimed to compare the results of the speech-ABR test between wakefulness and sleep states.
Methods: Sixteen young male adults (aged 20–28 years) with normal hearing participated in this study. The speech-ABR to the /da/ syllable was recorded during wakefulness and sleep. Electroencephalography (EEG) and behavioral tests (eyes position, body movements, etc.) were monitored during the test time to confirm the sleep state.
Results: The speech-ABR test parameters showed significant changes during sleep compared to wakefulness (latencies of waves V and A were longer and the amplitudes of waves V and A, the slope of V-A complex, and the spectral magnitude of F1 were lower). However, the spectral magnitude of higher frequencies was not significantly different. In addition, no significant statistical difference was observed in speech-ABR parameters between right and left ears.
Conclusion: Although the speech-ABR originates from brainstem centers, unlike conventional click-evoked ABR, it is affected by sleep as it is affected by the higher-level auditory processing functions. Although, further studies are needed. However, our study opens the way for many applied auditory studies about the possibility to use speech-ABR for auditory processing assessments in sleep state of different population groups, such as neonates.

Background and Aim: Hearing-impaired individuals have difficulty comprehending and producing speech sounds. Cochlear implantation is used to augment hearing. The present study aims to compare the production of fricatives /s/ and /ʃ/ and affricate /ʧ/ by Persianspeaking Cochlear-Implanted (CI) and Normal-Hearing (NH) children.
Methods: Fifteen Persian-speaking NH children and 15 Persian-speaking CI children, matched for age, gender, and general health conditions, were included in the study. The stimuli included two voiceless Persian fricatives /s/ and /ʃ/ and one voiceless Persian affricate /ʧ/ along with the open front vowel /æ/ in three Consonant-Vowel (CV), Consonant-Vowel-Consonant (CVC), and Vowel-Consonant (VC) contexts (/sæ/, /æsæ/, /æs/, /ʃæ/, /æʃæ/, /æʃ/, /ʧæ/, /æʧæ/, /æʧ/). After recording all utterances, Praat software was used to measure the friction duration, rise time, and spectral peak of the consonants.
Results: The CI children could not distinguish between /ʃ/ and /ʧ/ and produced affricate /ʧ/ as an allophone of /ʃ/ (p=0.01). Moreover, distinguishing between two fricatives /s/ and /ʃ/ was difficult for both groups. While NH children slightly treated these two sounds differently, the CI group produced fricative /s/ as an allophone of /ʃ/ (p=0.02). The rise time of /ʃ/ was longer in the NH children, except for /ʧæ/, where the CI children had a longer rise time.
Conclusion: The speech of CI children is different in producing /s/, /ʃ/, and /ʧ/ from their NH peers. The results can help speech therapists, clinical linguists, and application designers focus on speech sounds that are challenging for CI children to produce.

Background and Aim: Perception of speech in noise (SIN) is based on the accurate extraction of spectral and temporal cues. Disruption of this process can reduce the productivity of the spectral and temporal features of the target stimulus and speech recognition in noise. Auditory processing disorder is one of the main challenges of people with stroke, which leads to social, mental, and even physical failures. This study aimed to investigate the spectral and temporal processing abilities of people with stroke compared to healthy peers.
Methods: In this study, participants were 15 patients with stroke referred to the neurology clinic of Imam Khomeini Hospital and 30 healthy people aged 20–60 years. Spectral Modulation Detection Test (SMDT), Pitch Pattern Sequencing Test (PPST), Random Gap Detection Test (RGDT) and QuickSIN tests were performed for all participants. The mean scores of the two groups were compared.
Results: Patients with stroke had poorer performance in SMDT, PPST, RGDT and QuickSIN tests (p<0.001) compared to healthy subjects. The results showed that there was a significant correlation between SIN test with temporal and spectral processing in the normal group, but the correlation pattern was different in people with stroke. The scores of all the tests were not significantly different between the right and left ears.
Conclusion: The results showed that people with stroke have poorer performance in all tests compared to normal people and have more problems in speech perception in challenging areas.

Background and Aim: The Acceptable Noise Level (ANL), which is an effective clinical tool for quantitative assessment of noise tolerance, is affected by some known variables related to both subject and testing materials. The present study examined how the characteristics of different babble noises may affect the ANL results in normal adult listeners.
Methods: Forty Persian listeners with normal hearing participated. In addition to typical ANL testing with 12-talker noise, the ANL was obtained in 8 different conditions varying in number of talkers from 2 to 10 in the babble noises presenting forward and backward.
Results: There was a significantly lower ANL for 2-talker babble compared to 4, 8, 10, and 12-talker babble in both forward and backward noise conditions. With the increase in talkers in noise, the ANL becomes worse but reaches almost a plateau with more than 4 talkers in babble noise. There was a statistically significant difference between 2-talker forward and 2-talker backward noises, with no difference for the other conditions.
Conclusion: This finding that the ANL is affected by the number of talkers in babble noise and by the forward and backward background noise suggests that informational masking and listening in dip mechanisms are involved in ANL for normal hearing people at least.

Background and Aim: The output Signal-to-Noise Ratio (SNR) is one of the essential factors in hearing aid benefits. There is limited evidence regarding SNR improvement by the Channel-Free (CFHA) and Multi-Channel Hearing Aid (MCHA) and the speech understanding in noise through them. This study aimed to investigate the extent to which output SNR was modified by CFHA and MCHA processing and the variation in aided speech recognition abilities with a change in output SNR.
Methods: Thirty-six participants aged 50–65 years were included. A chosen CFHA and MCHA were used to obtain the output SNR and sentence recognition in noise in four different processing algorithms (linear, linear+noise reduction, WDRC, WDRC+noise reduction). Hagerman’s phase inversion technique was used to measure the attenuation of noise and, in turn, to obtain the output SNR of the hearing aid.
Results: In all hearing aid processing algorithms among those with normal hearing and people with hearing loss, the output of CFHA revealed higher attenuation values than that of MCHA. There was a significant effect of the hearing aids and processing algorithms in both normal and individuals with hearing impairment on the mean SNR. Further, multiple linear regression analysis results showed that whether the hearing is channel-free or multichannel significantly predicted speech recognition scores, while output SNR and processing algorithms did not.
Conclusion: The signal processing algorithms in CFHA had greater noise attenuation values, better output SNR, and speech recognition scores, showing an advantage over the modern MCHA among individuals with hearing impairment.

Background and Aim: Previous studies have shown promising findings on effectiveness of noisy Galvanic Vestibular Stimulation (nGVS) in various cognitive disorders. The connections of the vestibular system with the hippocampus has been proven. Here we investigated the effect of vestibular galvanic stimulation on the improvement of spatial learning and memory of rats.
Methods: Twelve Wistar rats were randomly divided into control and nGVS groups. The nGVS group underwent 30-minute sessions of stimulation at sub-threshold levels for a duration of fourteen days. Following the intervention, both groups underwent assessments of cognitive indices through the Morris water maze task, hippocampal neuronal spike rate by Single-Unit Recording (SUR) and the concentrations of c-fos protein in the hippocampus were measured using ELISA device.
Results: The nGVS group exhibited a significant difference compared to the control group in both the time taken to reach the target platform and the percentage of time spent in the goal quarter during the Morris water maze test. The nGVS treatment significantly enhanced spike rate of hippocampal dentate gyrus (p<0.01) compared to the control group. Additionally, c-fos protein concentrations were increased in the nGVS (5.833) than the control group (4.126), (p<0.001).
Conclusion: According to the obtained results, nGVS plays a role in improving spatial memory, and a longer duration of intervention is suggested to achieve more obvious improvement results.

Background and Aim: Melanocytes are cells in the skin, hair, and eyes that generate pigment called melanin, which is primarily responsible for the pigmentation of these structures. These melanocytes, known as the Cochlear Melanocyte, are also present in the human ears (especially in the cochlea) and play a significant role in fostering endocochlear potential and preventing the odds of hearing loss. The current study investigated the relationship of skin pigment with cochlear function through distortion product otoacoustic emission in Indian skin type.
Methods: A total of 120 participants aged between 17 to 25 were included using a purposive sampling technique. The subjects were further grouped based on a questionnaire on Fitzpatrick Skin Phototype (FSP) developed by Thomas Fitzpatrick (1975) and categorized as type III- type VI suitable for Indian skin types. Along with routine audiometric evaluations, the cochlear functioning was assessed using distortion product otoacoustic emissions. The standard group research design was used, and as data was normally distributed, multivariate analysis of variance was used to compare across groups.
Results: The results of multivariate analysis of variance (MANOVA) showed no significant differences across the four groups for both amplitude and the slope of distortion product otoacoustic emissions.
Conclusion: The present study using otoacoustic emissions revealed that the skin pigmentation did not affect cochlear functioning in the Indian population (type III through type VI) as seen in type I and II.