Background and Aim: Learning disability(LD) is one of the most prevalent problems among elementary school children. Approximately 10 percent of all elementary school children suffer from this problem. It has been determined that learning disability is predominantly accompanied with subtle impairment in central auditory nervous system. The main idea of this study was to evaluate middle latency auditory evoked potential (MLAEPs) in learning disabled children.

Materials and Method: This cross-sectional study investigated middle latency auditory evoked potential in children with learning disability (n = 31) compared to normal children (n = 31). Latencies and amplitudes of MLAEPs results with different stimulus intensity and binaural stimulation were compared between two groups.

Results: Compared to control group, learning disabled children exhibited smaller amplitudes for all the components except the right ear Na and Pa. There is no significant difference between two groups for latencies of the components.

Conclusion: It seems that middle latency auditory evoked potential may be useful in diagnosis and evaluation of learning disabled children although more investigation is required.

Background and Aim: Middle latency auditory evoked potentials (MLAEPs) development takes longer time than the auditory brainstem response (ABR) development does, which makes them difficult to record in some children. The purpose of this study was to investigate the age effect on characteristics and detection of MLAEPs in children and adults.
Materials and Methods: This cross sectional study was conducted on 15 children aged   7-12 yr and 31 adults aged 20-50 yr with normal peripheral hearing. To investigate precisely, children were divided in two subgroups of older and younger than 10 years old, as well. The MLAEPs amplitudes and latencies were recorded by conventional protocol and compared.
Results: Adult Na mean latency, 20.86 ms, was less than that of children, 22.86 ms, (p=0.0025).  In contrast, the adult Nb mean latency, 44.93 ms, was longer (p=0.0001). Children Nb mean latency was 42.02 ms. There was no significant difference in MLAEP amplitudes and latencies between two children subgroups, although variance was more in younger children.
Conclusion: MLAEPs are reliably recorded after 7 years old. Characteristics of MLAEPs are different in adults and children so that the primary MLAEPs generators have a course of development extending beyond the first decade of life. As those potentials were recorded in all children, it is suggested to be used in their test batteries for hearing evaluation.

Background and Aim: Universal newborn hearing screening program (UNHS) using otoacoustic emission (OAE) has been expanded dramatically. The aim of this study was to compare the characteristics of OAE in different time periods.

Methods: In this cohort study, 54 well babies were tested using screening transient-evoked otoacoustic emission in 12, 24, 36, 48 hours and 1 week of their age in Tamin Ejtemaii hospital of Zahedan, Iran. Parameters of "pass" and "fail" level, duration of the test, repetition rate for getting definite result and cooperation level of the parents were analyzed.

Results: The failing rate decreased markedly with age. The major part of this decrement concerned to the age of 12 to 24 hours (left ear: p=0.012 and right ear: p=0.057). Only for the age of 12 hours, the test repetition reduced the failing rate significantly (left ear: p=0.001 and right ear: p<0.001). The test duration reduced significantly with age increment and decreased from the 75 second in age 12 hours to 21 second in age of 24 hours. The test time median for 36, 48 hours and one week of age was 13, 8.4 and 14.3 second, respectively. Among the 54 parents requested to come back for retest one week later, 5 (9.3%) cooperated.

Conclusion: Age effect on referral rate were confirmed in this study high referral rate and poor parent cooperation were the main problems in universal newborn hearing screening program in Zahedan city.