Objective: The purpose of this study is to measure the hearing level among smokers using high frequency sensitive testing which are extended high frequency Pure Tone Audiometry (EHFPTA) and Distortional Product of Otoacoustics Emissions (DPOAE). This study focuses on four specific objectives which determine the hearing level of smokers at high frequencies, identifying amplitude of DPOAE in measuring damage level of hearing cell in cochlea, correlating the smoking duration on hearing and lastly, smoking quantity per day effects on hearing. Methods: 30 subjects participated in this study whereby they were divided into testing groups (smokers) and control groups (non-smokers). Results: The result of this study found that there are elevation of threshold at 16 KHz, 18 KHz and 20 KHz among smokers compared to non-smokers depending on duration (years) and quantity of smoking (per day). The higher the number of cigarettes being smoked per day, and the longer duration of smoking, the higher the potential of getting hearing loss. This study result also found that the longer the duration of smoking (years), it also may increase the chance of hearing elevation especially at high frequency. Mean amplitudes of DPOAE among smokers was significantly low compared to non-smokers except on 1.5 KHz and 8 KHz. Conclusion: This study implies that the damaging effects of smoking tend to reduce the hearing sensitivity at extended high frequency first which later can be progressively affected on other frequency range of hearing
Introduction: Children with dyslexia have disparate visual attention while reading varied structures of grapheme-pho- neme that have different congruency. Exploring more related with attention and reading disability, we investigated the visual attention, topographic mapping and correlation of ages of children with dyslexia using ERP study. Methods: A quantitative cross-sectional, non-interventional study was performed with simple randomization to select partici- pants. A total of 24 children were recruited into two groups; control (n=12) and dyslexic (n=12) groups. 128-ERP net was used for ERP experiment. Congruent (true meaningful Malay, 80%) and incongruent (meaningless, 20%) words were used for stimuli. Participants pressed button ‘1' and ‘2' when they saw congruent and incongruent words, re- spectively. Amplitudes and latencies of P300 ERP component were analysed at 19 electrode sites in 10-20 system. Results: Dyslexics evoked significantly higher P300 amplitude at T6 and shorter P300 latency at Fp1 areas compared with the control group. Moreover, pseudo word stimulations showed a high P300 voltage distribution in the prefrontal and right occipital area in the dyslexics, whereas there was more activation in the bilateral occipito-parietal areas in the controls. Significantly moderate positive correlation was found in the control group at F3, F7 and negative correlation in the dyslexic group at T4 areas for P300 latency. Conclusion: Children with dyslexia have higher visual attention with fronto-central topographic distribution for true Malay words and prefrontal and right occipital areas for pseudo Malay words. Age correlation results indicated that attention is directly related to the brain maturity of children.