Auditory and Vestibular Research
Volume:19 Issue: 1, 2010

Previous studies suggest that auditory stimulus frequency in normal subjects contribute to both P300 amplitude and latency measures. As occipital cortex devotes to other modalities including auditory inputs, the purpose of this study was to determine the effects of stimulus frequency in early blind subjects.

fifteen early blind subjects (8 males and 7 females) with mean age of 25.13±4.27 years were tested. Cognitive potential P300 was recorded in response to high (1000/2000 Hz) and low (250/500 Hz) frequencies auditory stimuli using an oddball task in 70 dB nHL. While participants answered to target stimulus, amplitude and latency of P300 was recorded.

With high frequency stimuli, mean amplitude in early onset blind subjects obtained 14.13 ±5.53µv and was 17.59±8.17µv with low frequency. With high and low frequency, mean latency of P300 obtained 295.60±31.33ms and 317.38±21.71ms respectively.Comparison of results between two stimuli showed that there were statistically significant differences between amplitudes (p=0.008) and latencies (p=0.001) of cognitive potential P300.

Changing low frequency to high frequency results in decreasing both amplitude and latency. It seems that auditory stimuli frequency affect the P300 parameters in blind subjects.

Evaluation of hearing-impaired children's auditory skills by a valid test is very important before starting auditory training. There are many different tests available for languages other than Persian, and some limited Persian tests for children above 5 year of age as well. Accordingly considering the importance of early intervention, we aimed to design a test for evaluating auditory skills of 3-4 year-old hearing-impaired Persian (Farsi) children, which is not available to date. The study method was test (scale) construction. The test named Tavana includes four subtests: detection, discrimination, identification and sentence comprehension. For determining content validity of the test, the vocabulary of 3-4 year-old normal-hearing and hearing-impaired children and also the comments of seven specialists were applied. We classified 10,10,8 and 6 sub skills for 1st to 4th subtests, respectively. The content validity of Tavana test's subskills were 100%, 83%, 96% and 95%, respectively (mean=94%). Mean time for test performance was 82 minutes. Content validity of Tavana test was 94% which was statistically valid compared to Modarres test (97%) and Mazaheryazdi test (88%).

listening, speaking, reading and writing are considered the lingual skills. These skills are in direct relation with each other. Listening is the first skill learnt by the individual through development. If damaged by hearing impairment, listening can cause serious defect to lingual skills. The goal of our research was to study the effect of hearing loss on reading literacy in hearing impairment students in comparison with normal hearing students. Study was performed using the examination booklets of Progress in International Reading Literacy Study (PIRLS) 2001. 119 hearing impairment students of 4th grade primary school, last year guidance school, and last year high school levels in schools providing exceptional student education were included. These individuals were compared to 46 normal hearing students of 4th grade primary school of ordinary schools. Comparative statistical analysis was performed using t-test. Reading literacy and literal contents understanding was shown to have a significant difference between normal hearing and whole hearing impaired student (p<0.05), except the ones in high school level with moderate hearing loss. There was also seen a significant difference between normal hearing and hearing impairment students in understanding of information contents (p=0.03). Hearing loss has a negative effect on reading literacy. Consequently, curriculum change and evolution of educational programs in exceptional centers is needed, in order to promote reading literacy and to enhance rest hearing

Learning language is acquired in early childhood and gradually developed by new words and new structures. Hearing sense is the most important acquisition for learning this skill. Hearing disorders are barriers for natural language learning. The purpose of this study was to investigate the relationship between writing sentences and perception of written sentences in hearing-impaired and normal-hearing students. A cross-sectional study was conducted among thirty hearing-impaired students with hearing loss of 70-90 dB and thirty normal hearing students. They were selected from 3rd grade primary school students in Hamadan, a large city in Western Iran. The language skills and non language information was assessed by questionnaire, Action Picture Test, and Sentence Perception Test. Results showed that there was a significant relation between writing sentences and perception of written sentences in hearing impaired students (p<0.001), (r=0.8). This significant relation was seen in normal-hearing students as well (p<0.001), (r=0.7). Disability of hearing-impaired students in verbal communication is not only related to articulation and voice disorders but also is related to their disability to explore and use of language rules. They suffer lack of perception of written sentences, and they are not skilled to convey their feelings and thoughts in order to presenting themselves by using language structures.

Hearing has an important role in speech production and making phonological distinction, especially voicing distinction. Voice onset time (VOT) has been a reliable acoustic cue of voicing differences in plosive consonants. The purpose of this study was to measure VOT in initial Persian (Farsi) oral plosives produced by cochlear implanted children, comparing to normal hearing children. In this cross-sectional study, 20 cases and 20 controls were assessed. Cases were prelingually deaf children who were cochlear implanted 4.5 years prior to test. Controls were normal hearing children at 4.5 years of age. VOT were measured while children uttered oral plosives. The effect of hearing status, voicing, and gender on VOT were assessed. The amount of VOT of plosives produced by girls was higher than boys, in both groups. This difference was significantly higher in voiceless plosives than in voiced ones. In both groups, voiceless plosives had long-positive VOT value; while the amount of VOT was short-positive regarding voiced plosives. It was demonstrated that VOT is significantly correlated with voicing. In voiceless plosives, VOT could not be considered as a phonetic correlate of hearing status; whereas it made significant differences between cochlear implanted children and hearing controls. Furthermore, it was confirmed that concerning voiceless plosives, the amount of VOT of girls was significantly higher than boys. On the contrary, in voiced plosives, gender had no significant effect on the amount of VOT.

Contralateral stimulation with noise can improve auditory intensity discrimination. This may be related to function of the efferent system. The purpose of this study was to determine the relationship between the auditory intensity discrimination and the efferent system function. Twenty students with normal hearing were included in this descriptive-analytic study. We examined Difference Limen for Intensity (DLI), Otoacoustic Emissions suppression and Speech In Noise. DLI was evaluated with and without contralateral noise stimulation at two different stimulus levels (20, 70 dB SL). There was significant difference between mean DLI scores of with contralateral masking comparing to without it, which was more prominent as frequency increased. Mean DLI score while masking with white noise was more than mean scores when masking with narrow band noise (p<0.05). Transient evoked otoacoustic emissions responses decreased significantly in amplitude with contralateral masking. (p<0.05) These results suggest that medial olivocochlear bundle functions as a key role in auditory intensity discrimination

Turner syndrome is the most common sex chromosome abnormality in females, affecting an estimated 3% of all conceiving females. Otologic disease is a common problem in Turner syndrome patients that is due to a combination of small dysfunction Eustachian tube, palatal dysfunction and cochlear malformation.

This study assessed the otologic and audiologic characteristics of a group of Turner syndrome patients. We studied 40 Turner patients aged 10 to 20 years (mean age: 15.84 years, SD=2.67). Pure tone audiometry was carried out for all of them.

Forty percent of the patients reported a history of middle ear disease. Analysis of audiometric data in 40 patients tested reveals normal hearing in 47.5%, pure sensorineural hearing loss in 32.5%, pure conductive hearing loss in 17.5% and mixed hearing loss in 2.5% of patients.

Careful follow up during early childhood of children with Turner syndrome is necessary to detect middle ear disease and prevent the probable sequel. However, long term periodic follow up is mandatory even after resolution of middle ear disease to detect sensorineural hearing loss.

Understanding and defining developmental norms of auditory comprehension is a necessity for detecting auditory-verbal comprehension impairments in children. We hereby investigated lexical auditory development of Persian (Farsi) speaking children. In this cross-sectional study, auditory comprehension of four 2-5 year old normal children of adult's child-directed utterance at available nurseries was observed by researchers primarily to gain a great number of comprehendible words for the children of the same age. The words were classified into nouns, verbs and adjectives. Auditory-verbal comprehension task items were also considered in 2 sections of subordinates and superordinates auditory comprehension. Colored pictures were provided for each item. Thirty 2-5 year old normal children were randomly selected from nurseries all over Tehran. Children were tested by this task and subsequently, mean of their correct response were analyzed. The findings revealed that there is a high positive correlation between auditory-verbal comprehension and age (r=0.804, p=0.001). Comparing children in 3 age groups of 2-3, 3-4 and 4-5 year old, showed that subordinate and superordinate auditory comprehension of the former group is significantly lower (p<0.05) than the others. Intra-group comparisons revealed no significant difference between nouns, verbs and adjectives (p>0.05), while the difference between subordinate and superordinate auditory comprehension was significant in all age groups (p<0.05). Auditory-verbal comprehension develop much faster at lower than older ages and there is no prominent difference between word linguistic classes including nouns, verbs and adjectives. Slower development of superordinate auditory comprehension implies semantic hierarchical evolution of words.

Speech as a motor phenomenon requires repetitive and rapid function of articulatory organs performing extremely fine movements. Practice on motor skills results in facilitation in treatment progress of children with phonological disorders. The purpose of this study was to compare motor skills in 5-year-old children with phonological and phonetic disorders. Thirty-two children age 5 years, 16 with phonemical speech sound disorders and 16 with difficulty at a phonetic level participated in this study. TOLD Test was performed for linguistic skills investigation among children. Phonetic test, Wepman test, diadochokinesis and oral assessment was used for diagnosis between phonological and phonetic disorders. The children were also evaluated with Oseretsky motor developmental scale. In comparison, mean scores of movement skills between both groups showed significant difference (p=0.006) and children with phonetic disorder got significantly higher scores on all part of this test. The findings of this study support the idea that speech sound disorders are frequently associated with motor problems, and that type of articulation disorder affects the motor performance in a different way. Phonological disorders seem to have more impact on motor performance than phonetic disorders. The results authenticate the need to pay more attention to the motor skills of children with articulation disorders.

Agrammatism is a phenomenon of neuropsychological relevance which has been recently investigated from conceptual and empirical aspects. The present study focuses on grammatical deficit in agrammatic aphasia. We evaluated the impairment of correct use of tenses of Persian verbs in agrammatic Broca's aphasia. Eight patients (mean age 57 years) participated in this descriptive - analytic study. They were classified as agrammatic Broca's aphasia according to the Persian aphasia test, their CT Scan and MRI reports and other inclusion criteria. All patients but one were monolingual native speakers of Persian (Farsi). The other individual was bilingual whose dominant language was Persian. All subjects had a left unilateral brain lesion for at least one year after the onset of brain damage. The written sentence completion and picture sentence completion tests were designed and performed. Results do not indicate significant difference between Past Tenses of verb; however, comparison of means showed best scores in Simple Past, Past Continuous, Present Perfect and Past Perfect, respectively. A main result of this study was significant difference between the mean of responses to Past Tense in comparison with Present Tense and Future (p=0.02). Use of tense is impaired in agrammatic Broca's aphasia in Persian. Our findings point out that use of Past Tense is impaired significantly more than the other tenses of verb

The correlation of stuttering and different linguistic factors is assessed in many studies. The obtained results can pave the way to reach a better understanding of stuttering, as well as finding more appropriate treatments. This study investigates the effect of utterance length on speech dysfluency comparing stuttering Persian(Farsi) -speaking children and nonstuttering ones. Ten stuttering and ten nonstuttering Persian-speaking children between 4 and 6 years of age, matched by age and gender where included in this cross-sectional study. All individuals were investigated by ten sets of simple and complex sentences. Morphemes were added one by one to sentences in each set in order to assess the impact of utterance length on dysfluency. Data analysis was performed using SPSS software. In practicing ten sets of sentences, the speech dysfluency shows significant enhance with increase of utterance length in both stuttering and nonstuttering children (p=0.001). Furthermore, while comparing two groups of simple and complex sentences, significant increase of speech dysfluency was observed by length enhance of utterance, in both stuttering and nonstuttering children (p<0.05). The comparison of stuttering and nonstuttering children showed significant difference between the two groups as well (p=0.001). The results of this study show that increase in utterance length in both simple and complex sentences lead to increase in dysfluency in stuttering and nonstuttering children. Stuttering children indicated more dysfluency than nonstuttering ones.

Reading is undoubtedly an essential skill for everybody in these years. Reading disorders or dyslexia can cause several problems for those who suffer from them. Early assessment and diagnosis play an important role in treatment of this disorder. The main aim of this study was determining the prevalence of reading disorder in first to fifth grade elementary school students. The subbasic aim was introducing the screening Inventory Reading Test (IRT) for diagnosis of the Students with reading disorder at elementary schools. A total of 200 students (boys and girls) in five elementary education grades in Isfahan were selected through multi-stage random sampling method and assessed by IRT in 2008. Descriptive statistical analysis was performed using SPSS Software package version 13.0 for Windows. This survey revealed the highest prevalence of reading disorder in the first grade male students (25%), and the lowest in fifth grade female students (0%). The incidence of dyslexia in all grades generally was 10%. The overall incidence was 66% for male students and 34% for female students. Reading disorder is more prevalent among male students than female students and the Inventory Reading Test is a satisfactory tool for rapid diagnosis of reading disorder.