Background and Aim: Hearing impairment affects all aspect of individual life, specially language and communication skills. When hearing impairment is congenital or occurs early in life, the child's ability to learn optimally through audition, will be affected. The aim of this study was to evaluate linguistic skills of preschool hearing impaired children and compare these skills with normal peers.

Methods: This descriptive cross-sectional study was performed on 38 preschool hearing impaired children that the main handicap was severe to profound hearing loss with ability to communicate orally and 28 normal children with the same cultural and social context. Twenty four non linguistic variables including age, gender, the age of entrance of preschool center, number of hearing aids, etc. were obtained by filling a questionnaire and fifteen linguistics variables including number of utterance, morphemes, correct utterance, noun phrase, ambiguous utterance, correct sentences, compound sentences, etc. were collected by some part of TOLD-P-3 test and three complementary questions. Then we compared the data from two groups.

Results: There were significant differences between number of utterance, number of correct mean length utterance, number of well-formed sentences in normal and hearing impaired group (p<0.000). There were no significant difference between unintelligible utterances, repetitive utterances and bad-formed sentences between two groups(p>0.05).

Conclusion: This study showed a severe deficit in linguistic skills in preschool hearing impaired children.

Background and Aim: There are four fundamental processes of attention: working memory, top-down sensitivity control, competitive selection, and automatic bottom-up filtering for salient stimuli. Each process makes an essential contribution to attention. Voluntary control operates on the first three processes in a recurrent loop. We reviewed comprehensive researches, theories, mechanisms, and central nervous system functions of auditory attention.

Methods: In this study, publications on auditory attention from 1953 to 2012 in PubMed, Scopus, ProQuest, Iran Medex, and Goole scholar were reviewed. Keywords were auditory attention and related words.

Conclusion: In general, auditory attention plays an important role in auditory processing and modulates this process from cochlea to auditory cortex through its four primary components.

Background and Aim: Children with auditory processing disorders and impaired phonological working memory have difficulty in storing an accurate phonological representation of speech.

Therefore, it is highly important to assess phonological working memory in this population. One of the methods in assessing phonological working memory is to use a non-sense syllable test. The aim of this study is to create a valid and reiable non-sense syllable test in order to evaluate phonological working memory in Persian speaking children with auditory processing disorders.

Methods: In this cross sectional comparative study, 40 non-sense syllable words were developed according to the criteria of non-syllable word construction and under supervision of a linguistic specialist. The non-sense syllable test was assessed in 53 boys and 47 girls from 7 to 10 years of age. The content validity of the non-sense syllable words was assessed by experts. To evaluate the validity of the test, correlation between the results of the test and forward digit recall and backward digit recall tests were measured. The non-sense syllable test was performed twice to evaluate its relaibility.

Results: The validity of the non-sense syllable test was 95.5 (SD=2). The correlation coefficient between non-sense syllable repetition, forward digit recall, and backward digit recal l tests were 0.76 and 0.75 respectively (p<0.001). The correlation coefficient between different performances of non-sense syllable tests was 0.8 (p<0.001).

Conclusion: These findings show that the non-sense syllable repetition test can be used to evaluate phonological working memory in Persian speaking children from 7-10 years of age.

Background and Aim: Auditory lateralization is a binaural phenomenon that is the result of processing of interaural time and intensity cues in the central auditory system. The main advantage of this phenomenon in human is understanding speech in noisy environments due to the auditory sciene analysis and cocktail party effects . The aim of the present study was to assess the auditory lateralization ability in normal children.

Methods: Participants were 80 normal school age children (8-11 years) of both genders, 42 girls and 38 boys. Lateralization functions were determined by interaural time difference (ITD) ranging from -880 to +880 µs and interaural intensity difference (IID) ranging from -10 to +10 dB for high-pass and low-pass noise.

Results: Interaural intensity difference lateralization functions were linear , while the interaural time difference lateralization functions were S-shaped with a clear linear component from -220 to +220 µs and with an asymptote from -440 to -880 µs and +440 to +880 µs. Generally, interaural intensity difference errors were significantly less than interaural time difference tasks (p<0.0001). Age effect was only present in interaural time difference tasks (p=0.001).

Conclusion: According to these results, children with the age of 11 years performed better in lateralization using interaural time difference cues compared to other children whereas there was no difference in performance in all ages when using interaural intensity difference cues.