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Background and Aim: Diabetes mellitus is a common disorder and causes a variety of central nervous system complications such as cognitive deficits. P300 auditory event related potential application is a well established neurophysiological approach in the assessment of cognitive performance. In this study, we compared the results of this application in patients with insulin-dependent (type I) diabetics mellitus and normal individuals.
Methods: In this non-interventional study, auditory P300 was measured in oddball paradigm by using two tone burst stimuli (1000 and 2000 Hz) on 25 patients with type I diabetics mellitus with the mean age of 28.76 years and 25 age-, education- and sex-matched healthy controls with the mean age of 29.68 years. The participants were enrolled by probable and category random sampling style.
Results: The mean P300 latency of the patients with type I diabetes mellitus was significantly prolonged compared with that of normal controls at all electrode sites and in both genders (p<0.001). The mean P300 amplitude of these patients was significantly lower compared with that of normal controls at all electrode sites and in both genders (p<0.001).
Conclusion: Significant prolongation in P300 latency of the patients with type I diabetes mellitus shows that auditory information processing and information categorizing are slower in them. Significant reduction in P300 amplitude of the patients with type I diabetes mellitus demonstrates that working memory in these patients cannot recognize new events and update its context in accordance with them.

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Background and Aim: Multiple sclerosis (MS) is characterized with inflammation, demyelization and gliosis. It may be relapsing, remitting, or progressive. Cognitive impairment is relatively prevalent in patients wit h multiple sclerosis and as duration of disease is longer as cognition impairment is more. To understand the cognitive impairment, event related potential can be considered as a valuable tool. This study aimed to investigate the influence of duration of disease and expanded disability status scale (EDSS) on the amplitude and latency of the event related potentials of P300 in patients with multiple sclerosis.

Methods: In this cross-sectional and non-intervention study, 21 patients with multiple sclerosis with mean age of 27.8 with SD 7.1 years (between 18 to 50 years) were enrolled. The patients were selected randomly. The correlation of P300 event-related potential and oddball paradigm was assessed, using two 1000 and 2000 Hz tone burst stimulus.

Results: There was a significant correlation between the latency of P300 wave and duration of disease and expanded disability status scale (p < 0.05) there was high correlation in both electrode sites (r>0.50). The correlation of amplitude of P300 and duration of disease and expanded disability status scale was not significant (p>0.05).

Conclusion: Significant correlation between the latency of P300 and the duration of multiple sclerosis and expanded disability status scale can be a sign of central nervous system changes. Besides, there is a relation between physical disability and cognitive impairments.

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Background and Aim: Patients with systemic lupus erythematosus (SLE) may develop hearing and balance disorders as a result of the immune-mediated inner ear damage. Vestibular evoked myogenic potential (VEMP) is a new vestibular test assesses the vestibulospinal tract. Balance disorders such as endolymphatic hydrops may occur as a result of perisaccular deposition of immune complexes in these patients. Although the vestibular system abnormality in the patients has been demonstrated, the function of the part of vestibular system including vestibulospinal tract has not been investigated so far. This study aimed to compare the vestibular evoked myogenic potentials between patients with inactive stage of systemic lupus erythematosus and normal individuals.

Methods: In this cross-sectional study, vestibular evoked myogenic potential was recorded between 26 healthy subjects and 20 patients with lupus erythematosus in inactive stage of disease aged 20 to 50 years old, using 500 Hz-tone bursts at 95 dB nHL.

Results: Vestibular evoked myogenic potentials responses were present in all (100%) of the participants. There was no significant difference in mean peak to peak amplitude and assymetry ratio between two groups. The mean p13 and n23 latencies were significantly higher in patients (p<0.05). Duration of disease had no effect on test parameters.

Conclusion: According to the prolonged latency of vestibular evoked myogenic potentials response in patients with lupus erythematosus , lesions in the retrolabyrinthine, especially in the vestibulospinal tract is suspected. Due to small sample size, there is no possibility for generalizing this result to all patients with lupus lupus erythematosus .

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Background: Balance disorders are common in patients following stroke. There are a number of physiotherapy modalities to treat balance impairments, one of which is vibration. The effects of vibration on balance disorders after stroke have not been investigated. This case report demonstrates the short-term effects of plantar vibration on the balance impairment of a patient with stroke.

Case presentation: A 72-years-old man with right hemiplegia resulted from stroke was admitted for vibration therapy after not responding to standard rehabilitation interventions. He complained of balance problems despite walking independently. Main studied outcomes were timed up and go test and posturography. Foot sensation, ankle plantar flexor spasticity, and the passive range of ankle dorsiflexion were assessed, as well. Vibration with a frequency of 100 Hz was introduced to the sole of the affected foot for 5 minutes. After intervention, all tests were improved compared to the baselines.

Conclusion: This case showed that the vibration was effective for improving balance disorder after stroke.

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Background and Aim: Phenylketonuria (PKU) is an inherited metabolic disease. The aim of this study was investigation the intelligence and language function in children with PKU based on the age of treatment onset and quality of dietary control.

Methods: In this cross-sectional study, the language and intelligence of 31 children with PKU at the age of 4 to 6.5 years were investigated by test of language development-third edition ( TOLD-3) and Wechsler preschool and primary scale of intelligence (WIPPSI), respectively the data compared with of 42 normal children. Patients were classified into 2 groups with different level of dietary control as good and poor [serum phenylalanine (Phe) level less and more than 6 mg/dl, respectively].

Results: There were significantly differences (p=0.001) between children with PKU and controls in intelligence and language scores. Early treatment improved significantly the intelligence and language scores in comparison with late treatment (p=0.019). Comparing late treatment before and after the age of 1 year showed that late treatment until 1 years of age improved significantly (p=0.050) all of functions except performance intelligence quotient (IQ). In early treated PKU, good dietary control improved significantly (p=0.021) and also, verbal and total IQ in comparison with poor dietary control.

Conclusion: Although, the language development in children with PKU is affected by age of treatment onset, cognitive development features such as verbal and total IQ is affected not only by the time of treatment onset but also by the quality of dietary control.

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Background and Aim: Fundamental frequency (F0) of onset is a reliable acoustic cue of voicing differences in plosive consonants. The purpose of present study was to acoustically analyze of the F0 amount of oral plosive consonants in the initial position of words in cochlear-implanted children and normal hearings.

Methods: In this study, the F0 of onset was measured in the speech production of 47 prelingual deaf children who were cochlear implanted about 61 months before the test (range: 47-76 months, SD: 8.6) and the results were compared with 60 normal hearing children who were 60 months old (range: 49-73, SD: 6.5).

Results: Using repeated measurement tests, it was shown that in all places of articulation, the amount of F0 of onset in voiceless plosives was higher than that of voiced ones, because of the low position of larynx and hyoid bone in voiced plosives. On the other hand, in most cases, the F0 of cochlear-implanted children was lower than that of normal hearings and in voiced plosives, there were significant differences (p=0.005) between cochlear implanted and normal hearing children. There was not any significant difference between the F0 of onset in girls and boys.

Conclusion: In all places of articulation, the mean amount of F0 of onset for voiceless plosives was higher than that of voiced plosives. There was significant difference between F0 of onset in cochlear implanted and normal hearing children.

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Background and Aim: Staggered spondaic words (SSW) test examines central auditory nervous system . Some researches show stuttering causes hyperactivity in motor system of the right hemisphere and cerebellum and decreases activity in the left hemisphere. During stuttering also, central auditory processing is decreased . The aim of this study was to compare the Persian staggered spondaic word test results between persistent developmental stutterers and normal subjects.

Methods: Thirty people with persistent developmental stuttering were participants of this cross-sectional descriptive-analytic study, which were aged 11 to 40 years. The control group matched for gender and number with stutters. They were 8 females and 22 males, with the age of 11 to 40 years, without any stuttering history, neurological diseases and auditory disorders.

Results: Stutterers were in normal category in corrected staggered spondaic words test. The mean scores of errors of right compete, right ear, left compete, left ear and total in corrected s taggered spondaic words between control and stuttering group showed significant differences. There was a significant relationship between stuttering and effect, too (p<0.05).

Conclusion: Based on the obtained results of this study, stutterers may have different cortical and sub - cortical brain activity than people who have not stutter . Central auditory processing abilities of stutterers are weaker than normal people.

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Background and Aim: Omega-3 fatty acid have structural and biological roles in the body 's various systems . Numerous studies have tried to research about it. Auditory system is affected a s well. The aim of this article was to review the researches about the effect of omega-3 on auditory system.

Methods: We searched Medline , Google Scholar, PubMed, Cochrane Library and SID search engines with the "auditory" and "omega-3" keywords and read textbooks about this subject between 19 70 and 20 13.

Conclusion: Both excess and deficient amounts of dietary omega-3 fatty acid can cause harmful effects on fetal and infant growth and development of brain and central nervous system esspesially auditory system. It is important to determine the adequate dosage of omega-3.

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Background and Aim: The auditory steady state response is a modern test for estimating hearing thresholds, especially in difficult to test individuals . However, there are few bone conduction auditory steady state response data, particularly for individuals with hearing loss. The objective of this study was to investigate bone conduction auditory steady state response thresholds in individuals with sensorineural hearing loss and normal hearing.

Methods: In a cross-sectional study, 10 individuals with normal hearing and 10 with sensorineural hearing loss at the age of 15-30 years were selected by non-probability sampling. Auditory steady state response and pure tone audiometry to bone conduction stimuli in 500 and 2000 Hz were recorded in two groups. Paired and independent t-test were used to compare data between the groups.

Results: There was low correlation between bone conduction auditory steady state response and pure tone audiometry in both groups (p>0.05 for both). The difference of behavioral thresholds and auditory steady state response in 500 Hz was higher than 2000 Hz in both groups (p=0.033 for normal hearing and p=0.017 for sensorineural hearing loss groups). Comparison of these results showed significant differences between the two groups (p<0.001).

Conclusion: In both groups, there was low correlation between bone conduction auditory steady state response and pure tone audiometry thresholds. In individuals with sensorineural hearing loss and in higher frequencies , bone conduction auditory steady state response thresholds was closer to pure tone audiometery thresholds.

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Background and Aim: Cerebrovascular accident is a neurological disorder involves central nervous system. Studies have shown that it affects the outputs of behavioral auditory tests such as dichotic auditory verbal memory test. The purpose of this study was to compare this memory test results between patients with cerebrovascular accident and normal subjects.

Methods: This cross-sectional study was conducted on 20 patients with cerebrovascular accident aged 50-70 years and 20 controls matched for age and gender in Emam Khomeini Hospital, Tehran, Iran. Dichotic auditory verbal memory test was performed on each subject.

Results: The mean score in the two groups was significantly different (p<0.0001). The results indicated that the right-ear score was significantly greater than the left-ear score in normal subjects (p<0.0001) and in patients with right hemisphere lesion (p<0.0001). The right-ear and left-ear scores were not significantly different in patients with left hemisphere lesion (p=0.0860).

Conclusion: Among other methods, Dichotic auditory verbal memory test is a beneficial test in assessing the central auditory nervous system of patients with cerebrovascular accident. It seems that it is sensitive to the damages occur following temporal lobe strokes.

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Background and Aim: Memory is one of the aspects of cognitive function which is widely affected among aged people. Since aging has different effects on different memorial systems and little studies have investigated auditory-verbal memory function in older adults using dichotic listening techniques, the purpose of this study was to evaluate the auditory-verbal memory function among old people using Persian version of dichotic auditory-verbal memory test. Methods: The Persian version of dichotic auditory-verbal memory test was administered to 23 old people ranging 60-80 years and 30 young people aging 20-30 years, with normal and symmetric hearing in both ears. The performance of the two groups was compared. Results: The mean score of young (6.36±0.43) and old (4.58±0.74) adults on dichotic auditory-verbal memory test were significantly difference (p=0.001). The correlation test showed a negative correlation between age and the memory scores in aged people (r=0.36). A significant difference in recall of early (p=0.034), middle (p=0.037), and final (p=0.041) words was seen between aged and young people. Conclusion: Based on the obtained results, significant reduction in auditory memory was seen in aged group and the Persian version of dichotic auditory-verbal memory test, like many other auditory verbal memory tests, showed the aging effects on auditory verbal memory performance.

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Background and Aim: Subjective tinnitus etiology has not been fully understood. Recently, in normal hearing subject one of the tinnitus theories, more specifically the medial olivocochlear tract, is related to the dysfunction of the efferent auditory system. The aim of this study was to determine the potential contribution of a defective cochlear efferent innervations to the chronic tinnitus in patients with normal hearing and determine the relation between tinnitus loudness and the amount of suppression of the transient evoked otoacoustic emission. Methods: This study was conducted on 20 tinnitus patients aged between 20-45 years and 20 controls matched for age and gender in School of Rehabilitation, Tehran University of Medical Sciences. Transient otoacoustic emission testing without and with contralateral white noise at 55 and 65 dB was performed on each subject. Results: The amplitudes of the emissions in the two groups was significantly different (p=0.001), but no correlation between tinnitus loudness and the amplitudes of the emissions in the presence (p=0.3) and absence (p=0.06) of contralateral noise. Conclusion: The suppression of the transient evoked otoacoustic emission by contralateral white noise did not reach statistically significant levels in tinnitus patients while the amplitude in control group reduced significantly.

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Background and Aim: Teachers are a large group of professional voice users that several risk factors and voice demands causes various voice complaints among them. As the voice is multidimensional, the aim of this study was acoustic and perceptual measurement of teachers’ voice and comparing the findings between two groups with many and few voice complaints.

Methods: Sixty female teachers of high school in Sari, north of Iran, were chosen by available sampling to participate in this cross-sectional study. According to a voice complaints questionnaire, 21 subjects located in few voice complaints and 31 in many voice complaints group. After a working day, subjects completed a voice self-assessment questionnaire. Also, teachers’voice were recorded during three tasks including sustained vowels /a/ and /i/, text reading and conversational speech. Acoustic parameters were analyzed by Praat software and 2 speech-language pathalogists performed auditory-perceptual assessment by GRBAS ( Grade, Roughness, Breathiness, Asthenia, Strain ) scale.

Results: Comparing of the voice self-assessment between the two groups demonstrated statistically significant difference (p<0.05) however results of the acoustic and auditory-perceptual measurement did not show significant diffrence.

Conclusion: Despite prevalent voice problems in teachers, there are various conditions in terms of complaints and assessments methods. In this study, only a remarkable deviation documented in the client-based assessments in many voice compliants group in comparison with few voice compliants, which would be probably related to different individual’s perception of voice problem between two groups. These results support paying attention to self-assessments in clinical process of voice problems.

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Background and Aim: Attention has causal role in speech and language processing. Studies are limited about relation between attention and language development. As a result, the purpose of this study was to investigate the difference shifting attention function in children with developmental stuttering and fluent speech.

Methods: Thirty children who stutter (21 boys and 9 girls) and thirty children who did not stutter (21 boys and 9 girls) were evaluated. Shifting attention function was investigated using Wisconsin card sorting test. The data were analyzed via Kolmogorov-Smirnov, independent t, and Mann-Whitney U-tests.

Results: Between group analysis showed significant differences for all of the indexes in Wisconsin card sorting test . The number of categories completed in children who stutter was significantly less than that control group (p<0.05). But preservative errors, total errors, total tries, time of test performance and try for first pattern in children who stutter was more than in the control group and data differences were significant for all of the indexes (p<0.05).

Conclusion: The findings of this study show that children with and without stuttering are different in shifting attention function and children who stutter have weaker function in shifting attention. The findings were linked to emerging theoretical frameworks of stuttering development and that were taken to suggest a possible role for attention processes in developmental stuttering.

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Background and Aim: Navigation information is processed and stored in different brain areas such as hippocampus. Since multiple pathways has been reported between vestibular nuclei and hippocampus and also cognitive dysfunction specifically in spatial memory is induced by vestibular deficits, it can be assumed that vestibular system stimulation ameliorates spatial memory. The aim of study was to evaluate the effect of galvanic vestibular stimulation on normal individual’s spatial memory.

Methods: In this experimental-interventional study, sixty 18-30-years-old women were randomly allocated in intervention and control groups. Intervention group undergone subthreshold bilateral bipolar galvanic vestibular stimulation and control group received sham stimulation. Stimulation was presented for 15 minutes. Corsi Block Tapping (CBT) test scores were compared before and after subthreshold bipolar galvanic vestibular stimulation exposure or no stimulation in each group and between groups.

Results: All test parameters were the same in both groups before stimulation (p<0.050). There were significant improvement in block span, total score and learning score in intervention group after galvanic vestibular stimulation (p<0.050), no significant difference in delayed score (p=0.600). Learning score was improved (p=0.003) and delayed score was deteriorated (p=0.010) in control group. Percentages of block span and total score in intervention group were significantly different compared to the other group (p<0.050).

Conclusion: Galvanic vestibular stimulation improves short-term and long-term spatial memory. This test may inherently have learning effect that is not influenced by stimulation.

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Background and Aim: Most of the researches are about bilingual children with specific language impairment and importance of it in recognition and treatment. This study aimed to assess verb morphology in bilinguals with specific language impairment (SLI) and compare them with normal bilinguals.

Methods: Six bilingual (Azeri and Persian) children with specific language impairment at the age of 7-8 years were collected from clinics of Tehran, Iran. They were evaluated about verb morphology using narrative speech and specific language impairment test and then, compared with six age-matched and six other language-matched children as control group. Children with specific language impairment were diagnosed by exhibiting a significant delay (more than one year) in language that can not be explained by intelligence deficits, hearing loss or visual impairment. We used Man-Whitney test for comparing the groups.

Results: Bilingual children with specific language impairment had delay in comparison with their age-matched group in subject-verb agreement (p=0.020) and articulating tense morphemes (p=0.019). They also had meaningful delay in using proper tense of verbs (past, present, and future) in comparison with language-matched control group (p=0.029).

Conclusion: Comparison of typical development of bilingual children and bilinguals with specific language impairment shows that verb morphology is a good clinical marker for diagnosing and treatment of these children.

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Background and Aim: Since utricle is the main damaged organ in benign paroxysmal positional vertigo (BPPV), ocular vestibular evoked myogenic potential (oVEMP) may be an appropriate method to evaluate the utricule dysfunction and the effect of disease recurrence rate on it. This study aimed to record myogenic potential in patients with benign paroxysmal positional vertigo.

Methods: In a cross-sectional study, ocular myogenic potential was recorded in 25 healthy subjects and 20 patients with benign paroxysmal positional vertigo using 500 Hz-tone bursts (95 dB nHL).

Results: In the affected ear, mean amplitude was lower and mean threshold was higher than those in the unaffected ear and in the normal group (p<0.05). Mean amplitude asymmetry ratio of patients was more than the healthy subjects (p<0.001). There was no statistical difference between the two groups regarding mean latencies of n10 and p15 (p>0.05). Frequencies of abnormal responses in the affected ears were higher than in unaffected ears and in the normal group (p<0.05). Furthermore, the patients with recurrent vertigo showed more abnormalities than the patients with non-recurrent (p=0.030).

Conclusion: In the recurrent benign paroxysmal positional vertigo, ocular vestibular evoked myogenic potential showed more damage in the utricle, suggesting this response could be used to evaluate the patients with benign paroxysmal positional vertigo.

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Background and Aim: Setting of candidates for a word with similar beginnings is known as the Cohort size. Despite the importance of the number and properties of candidates in word recognition, so far, in none of the tests made for Persian language, the Cohort size is considered. The purpose of current study was the introduction of importance of Cohort size in word recognition and calculation of Cohort size for the list of Persian high-frequency spondee words.

Methods: The spondee words extracted from high-frequency Persian word store. Then, total spondee words with same first syllable in Amid Persian dictionary recorded and Cohort size calculated for each spondee word. Thus, the list of high-frequency spondee words with their Cohort size composed of 4121 words obtained.

Results: The Cohort sizes of word had a wide range from 0 to 87. In the half of the words, the Cohort sizes were less than 14 and in the rest were more than it.

Conclusion: The Cohort size affects the time course and precision of decision making about words. Persian words are not equal in Cohort size. For having more controlled test materials to develop and design different types of auditory tests, it is possible to consider the Cohort size of words along other effective factors.

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Background and Aim: Although double dichotic digit test is a useful tool for assessing the central auditory system in adults, it is more useful for evaluating younger children. The present study aimed to develop the Persian version of the single dichotic digit test and to obtain initial normative data.

Methods: The Persian version of the present test consisted of three different sets of 25 single digit pairs for testing in the free recall, directed recall to right, and directed recall to left conditions. The digits in each list were recorded dichotically on a compact disc. The sectional study was performed on 126 male students, aged between 7 and 9. The test-retest reliability was assessed in 29 subjects two to four weeks after the first test session.

Results: In seven year olds, the mean right and left ear scores increased from around 95.79% and 89.69%, respectively. In eight year olds, the mean right and left ear scores increased from around 98.59% and 96.29%, respectively. The mean right ear advantage decreased from around 6.13% in 7 year olds to around 2% in 8 year olds (p=0.001). No significant difference was found in scores between the free recall and directed recall conditions (p>0.05). The test had a high test-retest reliability (p>0.05).

Conclusion: The Persian version of the test has a high test-retest reliability for evaluating male children aged between 7 and 9 it can be used for assessing binaural integration in male children of this age group.

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Background and Aim: Creatine plays an important role in the regulation of cellular energy in high energy demand organs such as the inner ear. It is also believed to play a protective role. This article reviewed the mechanisms and effects of creatine on the auditory and vestibular systems.

Recent Findings: Creatine transporters and creatine kinase enzymes are involved in converting creatine to creatine phosphate. Phosphate is a fuel cell available in the cochlear and vestibular hair cells and the protective cells, striavascularis, peripheral and central neural pathways to the auditory cortex. It provides essential ATP for auditory and vestibular system performance. Creatine kinase prevents cochlear damage by regulating the metabolism of energy in marginal layers of the striavascularis and preventing free radical production in stressful situations. It also plays an important role in vestibular compensation. Creatine kinase dysfunction leads to an increase in the threshold of auditory brainstem potentials and a reduction in vestibular performance. The use of creatine improves vestibular evoked myogenic potentials and neurologic symptoms.

Conclusion: Creatine and creatine kinase protein is essential for normal hearing and balance function and sensitivity. Creatine kinase deficiency impairs the functioning of these two systems however, creatine consumption may boost the sensitivity of the vestibular system and neurological performance. Effects of the creatine consumption on the auditory system have not yet been examined.