Auditory Effects Of Noise Research Articles

Noise-induced Vestibular Dysfunction

Noise pollution is an ever-increasing menace and affects the general and the mental well-being. The auditory effects of noise are well documented. However, noise induced vestibular dysfunction has received little attention and is an unexplored and an under-diagnosed entity. We review the effects of noise on the balance function. Various studies have shown the detrimental effects of noise on the vestibular end organs. Such changes may take place by various mechanisms and that noise induced vestibular dysfunction may occur in the absence of hearing loss. The long-term effects of noise on the vestibular physiology are not known and is an area for further research particularly in the setting of occupational noise exposure. It is imperative to understand the response of the vestibular system to noise at the molecular levels so that therapeutic measures can be adopted. At the same time, it is important to identify vestibular dysfunction at an early stage clinically so that further exposure can be prevented and permanent damage is averted.

Effects of Occupational Noise on Blood Pressure

BACKGROUND: Noise has been found to have non auditory effects. One of the possible non auditory effects of noise is its effect on blood pressure. Available data on the effect of noise on blood pressure has been found to vary. Hence, the aim of this study was to find if there is a predictive effect of noise on blood pressure.
 
 METHOD: Study was done among sawmill workers in Ile-Ife. The noise in each sawmill was measured with a sound meter and blood pressure of each participants were recorded. A regression analysis was done using systolic and diastolic blood pressures as dependent variables and noise as the predictor.
 
 RESULTS: A total of 420 sawmill workers were recruited into the study with an average age of 33.53±8.59 years. The average noise level in the sawmill was 88±1.87 dB and the average systolic and diastolic blood pressures were 132 ± 21mmHg and 85 ± 13mmHg respectively. There was no significant effect of noise on systolic blood pressure {F (1, 419) = 0.958, P>0.05} but there was a significant effect of noise on diastolic pressure {F (1, 419) = 7.543, P<0.05}.
 
 CONCLUSION: This study found that exposure to noise is a predisposing factor to increase in blood pressure.

Indoor environment and children's health: Recent developments in chemical, biological, physical and social aspects

Much research is being carried out into indoor exposure to harmful agents. This review focused on the impact on children's health, taking a broad approach to the indoor environment and including chemical, microbial, physical and social aspects. Papers published from 2006 onwards were reviewed, with regards to scientific context. Most of publications dealt with chemical exposure. Apart from the ongoing issue of combustion by-products, most of these papers concerned semi volatile organic compounds (such as phthalates). These may be associated with neurotoxic, reprotoxic or respiratory effects and may, therefore, be of particular interest so far as children are concerned. In a lesser extent, volatile organic compounds (such as aldehydes) that have mainly respiratory effects are still studied. Assessing exposure to metals is still of concern, with increasing interest in bioaccessibility. Most of the papers on microbial exposure focused on respiratory tract infections, especially asthma linked to allergens and bio-aerosols. Physical exposure includes noise and electromagnetic fields, and articles dealt with the auditory and non auditory effects of noise. Articles on radiofrequency electromagnetic fields mainly concerned questions about non-thermal effects and papers on extremely low-frequency magnetic fields focused on the characterization of exposure. The impact of the indoor environment on children's health cannot be assessed merely by considering the effect of these different types of exposure: this review highlights new findings and also discusses the interactions between agents in indoor environments and also with social aspects.

Cardiovascular effects of environmental noise: Research in the United Kingdom

Although the auditory effects of noise on humans have been established, the non-auditory effects are not so well established. The emerging links between noise and cardiovascular disease (CVD) have potentially important implications on public health and policy. In the United Kingdom (UK), noise from transport is a problem, where more than half of the population is exposed to more than the recommended maximum day-time noise level and just under three-quarters of the population live in areas where the recommended night-time noise level is exceeded. This review focuses on findings from studies conducted in the UK that examined environmental noise and cardiovascular disease. There were statistically no significant associations between road traffic noise and incident ischemic heart disease in the Caerphilly and Speedwell studies, but there was a suggestion of effects when modifying factors such as length of residence, room orientation, and window opening were taken into account. In a sample stratified by pre-existing disease a strongly increased odds of incident ischemic heart disease for the highest annoyance category was found compared to the lowest among men without pre-existing disease (OR = 2.45, 95%1.13 - 5.31), which was not found in men with pre-existing disease. In the Hypertension and exposure to noise near airports (HYENA) study, night time aircraft noise exposure (L night ) was associated with an increased risk of hypertension, in fully adjusted analyses. A 10-dB increase in aircraft noise exposure was associated with an odds ratio of 1.14 (95%CI, 1.01 - 1.29). Aircraft noise was not consistently related to raised systolic blood pressure in children in the road traffic and aircraft noise exposure and children's cognition and health (RANCH) study. There is some evidence of an association among environmental noise exposure and hypertension and ischemic heart disease in the UK studies; further studies are required to explore gender differences, the effects of day and night time exposure, and exposure modifying factors.

Effects of auditory noise on the psychophysical detection of visual signals: Cross-modal stochastic resonance

Harper [D.W. Harper, Signal detection analysis of effect of white noise intensity on sensitivity to visual flicker, Percept. Mot. Skills 48 (1979) 791–798] demonstrated that the visual flicker sensitivity was an inverted U-like function of the intensity of different levels of auditory noise from 50 to 90 dB (SPL), without concomitant changes in the response bias. The aim of the present study was to extend these observations in the context of the stochastic resonance, a counterintuitive phenomenon in which a particular level of noise enhances the response of a nonlinear system to a weak input signal. We show psychophysical evidence in a yes–no paradigm for the existence of a stochastic resonance-like phenomenon in the auditory–visual interactions. We show that the detection of a weak visual signal was an inverted U-like function of the intensity of different levels of auditory noise. Nevertheless, for a strong visual signal the auditory noise acts in detriment of the ability of visual detection. Our results suggest that auditory noise could be employed in vision rehabilitation interventions in order to improve the detection of weak visual signals.