Vol 21 No 3 (2012)

Published: 2012-10-01

Review Article(s)

  • XML | views: 119 | pages: 1-8

    Background and Aim: The somatosensory system is one of the most effective systems in balance control. It consists of peripheral and central components. Knowing the role of these components in balance control assists the developing of effective rehabilitation protocols. In some diseases peripheral components and in others central components are impaired. This paper reviews the effect of impairment of peripheral and central components of the somatosensory system on balance control.
    Methods: In this study publication about somatosensory impairments from 1983 through 2011 in PubMed, Scopus, ProQuest, Google Scholar, Iran Medex, Iran Doc and Magiran were reviewed. Medical subject headings terms and keywords related to balance, somatosensory, somatosensory loss, and sensory integration/processing were used to perform the searches.
    Conclusion: Somatosensory impairments either with peripheral or central origin, can cause problems in balance control. However, these problems are not considered in some patients. In these impairments, balance training is recommended to be used alongside other routine treatments in the patients' rehabilitation programs.

Research Article(s)

  • XML | views: 173 | pages: 9-17

    Background and Aim: Contralateral suppression of transient evoked otoacoustic emissions (TEOAEs) test evaluates the efferent auditory system. In this test, acoustic reflex is an important confounding variable. In recent years, application of this test is growing especially in children suspect to central auditory processing disorder. Therefore, the magnitude of influence of this confounding variable on the suppression of TEOAEs should be made clear. The aim of this study was to investigate the impact of acoustic reflex on contralateral suppression of TEOAEs.
    Methods: This research was performed on 39 normal-hearing adults of both sexes and of 18-26 years of age. Tests were used for the determination of interaural attenuation (IA), acoustic reflex, TEOAEs and contralateral suppression of TEOAEs.
    Results: TEOAEs amplitudes and their contralateral suppression were significantly higher in females and males respectively (p = 0.01). The amount of TEOAEs suppression before reflex activity ranged between 2000 to 3000 Hz. Activation of acoustic reflex significantly increased the magnitude of suppression in all frequency bands (p≤0.01) and maximum suppression occurred in 500 to 1000 Hz.
    Conclusion: For achieving accuracy of clinical findings, clinicians should always use suppressant levels lower than the acoustic reflex threshold. It is recommended that different norms for males and females be used in contralateral suppression of TEOAEs.

  • XML | views: 153 | pages: 18-23

    Background and Aim: Due to limitation of standardized tests for Persian-speakers with language disorders, spontaneous language sampling collection is an important part of assessment of language protocol. Therefore, selection of a language sampling method, which will provide information of linguistic competence in a short time, is important. Therefore, in this study, we compared the language samples elicited with picture description and storytelling methods in order to determine the effectiveness of the two methods.
    Methods: In this study 30 first-grade elementary school girls were selected with simple sampling. To investigate picture description method, we used two illustrated stories with four pictures. Language samples were collected through storytelling by telling a famous children’s story. To determine the effectiveness of these two methods the two indices of duration of sampling and mean length of utterance (MLU) were compared.
    Results: There was no significant difference between MLU in description and storytelling methods (p>0.05). However, duration of sampling was shorter in the picture description method than the story telling method (p<0.05).
    Conclusion: Findings show that, the two methods of picture description and storytelling have the same potential in language sampling. Since, picture description method can provide language samples with the same complexity in a shorter time than storytelling, it can be used as a beneficial method for clinical purposes.

  • XML | views: 120 | pages: 24-31

    Background and Aim: Recently, researchers have increasingly turned to study the relation between stuttering and syntactic complexity. This study investigates the effect of syntactic complexity on the amount of speech dysfluency in stuttering Persian-speaking children and adults in conversational speech. The obtained results can pave the way to a better understanding of stuttering in children and adults, and finding more appropriate treatments.
    Methods: In this cross-sectional study, the participants were 15 stuttering adult Persian-speakers, older than 15 years, and 15 stuttering child Persian-speakers of 4-6 years of age. In this study, first a 30 minute sample of the spontaneous speech of the participants was provided. Then the utterances of each person were studied in respect to the amount of dysfluency and syntactic complexity. The obtained information was analyzed using paired samples t-test.
    Results: In both groups of stuttering children and adults, there was a significant difference between the amount of dysfluency of simple and complex sentences (p<0.05).
    Conclusion: The results of this study showed that an increase in syntactic complexity in conversational speech, increased the amount of dysfluency in stuttering children and adults. Moreover, as a result of increase of syntactic complexity, dysfluency had a greater increase in stuttering children than stuttering adults.

  • XML | views: 160 | pages: 32-39

    Background and Aim: Auditory memory plays an important role in developing language skills and learning. The aim of the present study was to assess auditory verbal memory and learning performance of 18-30 year old healthy adults using the Persian version of the Rey Auditory-Verbal Learning Test (RAVLT).
    Methods: This descriptive, cross-sectional study was coducted on seventy 18-30 year old healthy females with the mean age of 23.2 years and a standard deviation (SD) of 2.4 years. Different aspects of memory, like immediate recall, delayed recall, recognition, forgetting rate, interference and learning, were assessed using the Persian version of RAVLT.
    Results: Mean score increased from 8.94 (SD=1.91) on the first trial to 13.70 (SD=1.18) on the fifth trial. Total learning mean score was 12.19 (SD=1.08), and mean learning rate was 4.76. Mean scores of the participants on the delayed recall and recognition trials were 13.47 (SD=1.2), and 14.72 (SD=0.53), respectively. The proactive and retroactive interference scores were 0.86 and 0.96, respectively. The forgetting rate score was 1.01 and the retrieval score was 0.90.
    Conclusion: The auditory-verbal memory and learning performance of healthy Persian-speaking females was similar to the performance of the same population in other countries. Therefore, the Persian version of RAVLT is valid for assessment of memory function in the Persian-speaking female population.

  • XML | views: 129 | pages: 40-50

    Background and Aim: Neurotologic signs and symptoms, especially vestibular symptoms, are common in migraine patients. The goal of this study was to investigate some parts of the central vestibular system using some subtests of videonystagmographic evaluation, including spontaneous nystagmus, gaze-evoked nystagmus, and smooth pursuit between their attacks of migraine.
    Methods: Thirty patients with migraine and 38 healthy volunteers of 18-48 years of age were included in this study. Spontaneous nystagmus, gaze-evoked nystagmus toward the right, left and upward, and also smooth pursuit using three different velocities were performed in both groups.
    Results: Five normal subjects and five migraine patients had spontaneous nystagmus, which was less than three degrees; there was no statistically significant difference between the two groups. No gazeevoked nystagmus was seen in both groups. In one velocity of smooth pursuit evaluation, gain and phase were significantly different. The statistical difference in gain and phase was not clinically important as it was in normal range of the device. Another statistically significant parameter was saccadic morphology of smooth pursuit which was seen in migraine patients.
    Conclusion: These results suggest the presence of subtle otoneurological abnormalities in migraine patients that is probably due to deficiency of oculomotor function with vestibulocerebellar origin.

  • XML | views: 138 | pages: 51-61

    Background and Aim: Valid identification, prevention, and treatment of language disorders have a high priority for the clinicians. Story retelling is a method for studying language development which is faster than other procedures in implementing and analyzing, and has a reliable scoring system. The aim of this project is to construct story retelling test for assessing language structure in 6-7 year old, Persian children.
    Methods: An appropriate story for 6-7 year old children was written by the help of a speech pathologist, a linguist, and a novelist. The validity of the constructed story was checked by 14 experts. Then related pictures were design and their validity was examined. The test was conducted on 72 children (36 girls, 36 boys) of 6-7 years. The reliability was administered with a test-retest design with a two week interval. The reliability of the scoring system was evaluated with inter-rater method.
    Results: Content validity index for this test was 89%, interclass correlation was 83%, and standard error of measurement was 2.76. The interclass correlation for scoring system was 93% and Pearson’s correlation was 90%. Correlation of the test-retest scores was statistically significant (p<0.01).
    Conclusion: This story retelling test has appropriate validity and reliability. It is suitable for quick assessment of language structure in 6-7 year old, Persian children.

  • XML | views: 99 | pages: 62-69

    Background and Aim: In many migraine patients prophylactic drugs are effective in reducing attacks and symptoms such as vestibular complaints. Therefore, related neural pathways are probably also affected. This study aimed to compare vestibular evoked myogenic potential in migraine patients under treatment with prophylactic drugs and those without any treatment.
    Methods: Subjects included 46 patients with migraine. They were evaluated in two groups; those under treatment with prophylactic drugs (21 subjects) and those without treatment (25 subjects). The age range of patients was 20-60 years. The vestibular evoked myogenic potential were recorded with 500 Hz tone bursts at 95 dB nHL.
    Results: Mean of amplitude ratio (p=0.02), and interpeak latency values in the right ear (p=0.03) and left ear (p=0.001) were higher in patients with prophylactic therapy than the group without therapy; this difference was statistically significant. There was no statistical difference between the two groups in terms of mean of latency of p13 and n23 peaks, and absolute amplitude (p>0.05).
    Conclusion: Prophylactic drugs probably improve mean of main response parameters of vestibular evoked myogenic potential in migraine patients with prophylactic therapy.

  • XML | views: 103 | pages: 70-76

    Background and Aim: Verb is one of the most important aspects of a sentence, and verb deficit is a noticeable part of developmental language disorders. In Iran, there is no standard test for evaluating this aspect of language in children. This study aimed to develop and evaluate a picture verb test for 36- 54 month-old normal Persian-speaking children, and assess its ability to differentiate between children.
    Methods: A list of verbs that could be depicted was collected and content validity was assessed by seven speech therapist. 55 verbs were selected. Then, three pictures were prepared for each verb and one of those pictures was chosen by the same seven specialists. 106 children aged 36-54 months participated in this study. They were divided into three groups (36-42, 42-48, and 48-54 months). Reliability of this test was assessed by Spearman’s correlation and internal consistency. Correlation between children’s scores and their age was calculated.
    Results: Content validity index of all verbs were 1. Spearman’s correlation of 0.89 and internal consistency of 0.60 was obtained. By deletion of item method, the Kuder-Richardson score was enhanced to 0.71. There was a significant correlation between children’s ability to respond and their age (r=0.76, p < 0.001).
    Conclusion: This test is a suitable tool for assessment of verbs in 36-54 month-old Persian-speaking children and can differentiate between three groups under study.

  • XML | views: 125 | pages: 77-85

    Background and Aim: Sound conditioning is exposure to a non-traumatic, moderate level of sound which increases inner ear resistance against further severe noise. In this study, we aimed to survey the effect of sound conditioning on auditory brainstem response (ABR) threshold shifts using click stimulus, and the effect of the frequency of conditioning on hearing protection.
    Methods: Fifteen guinea pigs were randomly divided into 3 groups. Two conditioned groups were exposed to 1 kHz, and 4 kHz octave band noise at 85 dB SPL, 6 hours per day for 5 days, respectively. On the sixth day, the animals were exposed to 4 kHz octave band noise at 105 dB SPL, for 4 hours. The control group was exposed to intense noise, 4 kHz at 105 Db SPL for 4 hours (without conditioning). After exposure, ABR thresholds using click were recorded an hour, and 7 days after noise exposure.
    Results: The results of the ABR with click stimulus showed less thresold shifts in conditioned groups than control (p≤0.001). Comparison of the results of conditioned groups, showed less threshold shift by 4 kHz conditioning, however, this difference was not statistically significant (p>0.05).
    Conclusion: Electrophysiological data of our study showed that sound conditioning has a protective effect against subsequent intensive noise exposure, and the frequency of conditioning does not have significant effect on ABR threshold shifts when using click stimulus.

  • XML | views: 130 | pages: 86-102

    Background and Aim: The current study has been designed based on the framework of the Stress Deafness Model (SDM), and aims at investigating native listeners’ general perceptual sensitivity to the acoustic correlates of stress in Persian, a language with predictable stress. According to SDM, more regularity in a language implies poorer perceptual sensitivity of its native speakers, as regular stress patterns will not require lexical encoding.
    Methods: The experiment was a modified method of adjustment task where subjects had to simulate stimuli played to them. A total of thirty five Persian speakers took part in the experiment and were placed in three groups based on their linguistic background. In addition to overall perceptual sensitivity, the effect of exposure to English and phonetic knowledge were also tested.
    Results: Persian speakers showed a weak perception of stress correlates. It was found, however, that exposure to English will improve stress deafness among Persian natives (p<0.0001). However, the results failed to show any significant effect by phonetic knowledge. It was also shown that the duration had the most erroneous perception by participants (p=0.0001), while there was no statistically significant difference between understanding fundamental frequency clues and intensity perception by listeners.
    Conclusion: Since Persian speakers showed an overall weak perception of stress correlates, the results support the predictions made by SDM.

  • XML | views: 202 | pages: 103-109

    Background and Aim: Hearing impaired individuals, who have undergone cochlear implantation, do not have satisfactory relationships with their peers and cannot be fully integrated into the hearing communities. The main purpose of this study was to examine the effect of a family-oriented social skills training program on cochlear implant users.
    Methods: In this experimental study, 16 volunteer families consisting of mothers and their 12-19 year old children, who had undergone cochlear implantation at least two years in advance, were chosen from 328 families, members of the Hearing Rehabilitation Association of Iran. They responded to social skills rating scale as pre-test after they were randomly assigned to control and experimental groups. The experimental group underwent a 12-session social skills training. The social skills rating scale was then administered as a post-test in the two groups.
    Results: The results showed the effectiveness of the family-oriented social skills training program on assertion (p<0.01), self-controlling (p<0.01), and general social skills (p< 0.01); however, they showed no significant effect on cooperation (p>0.05).
    Conclusion: The study revealed that family-oriented social skills training program is effective in improving the social skills of individuals with cochlear implantation. Therefore, this training program can be employed to improve these skills as an integral part of the rehabilitation program.