Noise effects on human performance: A meta-analytic synthesis.

Noise is a pervasive and influential source of stress. Whether through the acute effects of impulse noise or the chronic influence of prolonged exposure, the challenge of noise confronts many who must accomplish vital performance duties in its presence. Although noise has diffuse effects, which are shared in common with many other chronic forms of stress, it also exerts its own specific influences on various forms of cognitive and motor response. We present a quantitative evaluation of these influences so that their harmful effects can be mitigated, their beneficial effects exploited, and any residual effects incorporated and synthesized into selection, training, and design strategies to facilitate human performance capacities. Predictions of single and joint moderator effects were made on the basis of major theories of noise and performance, specifically those explanations based on arousal, masking, or cognitive-resource mechanisms. These predictions were tested through moderator analyses of effects as a function of task type, performance measure, noise type and schedule, and the intensity and duration of exposure. Observed outcome effects (797 effect sizes derived from 242 studies) varied as a function of each of these moderators. Collective findings identified continuous versus intermittent noise, noise type, and type of task as the major distinguishing characteristics that moderated response. Mixed evidence was obtained for the traditional arousal and masking explanations for noise effects. The overall pattern of findings was most consistent with the maximal adaptability theory, a mental-resource-based explanation of stress and performance variation. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

An index of the physical effort required in human task performance.

Conducted 2 studies to examine the relationship between ratings of perceived physical effort required in human task performance and associated metabolic expenditure. In each study, tasks whose metabolic performance costs were known from the physical work assessment literature were rated on the effort required to complete the task by Ss who did not know the metabolic information. Results of the 1st study with 26 personnel specialists reveal that Ss could discriminate among tasks of known metabolic differences and that their ratings of the effort required in task performance were highly correlated with actual metabolic costs. The 2nd study replicated the procedures and results of the 1st study, using 26 male and 28 female untrained observers and examined sex differences in ratings of perceived effort. No rating sex differences were found beyond the level of chance. Results are discussed in terms of the development of an assessment index of the physical effort required in task performance. (23 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The role of oxygen radicals in the physiology and pathology of human sperm

Reactive oxygen species in low doses are necessary compound of sperm capacitation and hyperactivation. Superoxide anion, hydroxyl radical and hydrogen peroxide initiate sperm capacitation. The edding of antioxidant enzymes inhibits the spontaneous and induced sperm hyperactivation. The process of capacitation is accompanied with the superoxide anion production output by spermatozoa. High doses of reactive oxygen species block the sperm motility through the inhibition of ATP synthesis by the mitochondrial enzymes and cell membrane compounds injury.     

Perceived control, effort, and academic performance: Interindividual, intraindividual, and multivariate time-series analyses.

A naturalistic study tested a model depicting how perceived control functions to regulate and interpret children's cognitive performances. Data, collected daily in the classroom over 4 mo, were organized around children's cognitive performances (graded assignments). For each homework and test, children provided information about effort, performance, attributions (effort, ability, concentration/help, task difficulty, and unknown causes), and expected control. The data formed a sequence of beliefs–performance–beliefs "loops" for each child. Although data at the interindividual level were consistent with the model, intraindividual data revised each link; furthermore, exploratory multivariate time-series analyses suggested that different models may best fit single Ss. Intraindividual implications included adding mediators to the model and designing interventions to fit individual children. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The influence of valence, instrumentality, and expectancy on effort and performance.

Used survey methodology to test an expectancy-valence model of work motivation with 70 male and 76 female Post Office employees in a training program to sort mail. The model predicted self-reported effort fairly well, but correlations with supervisory ratings of effort and performance were lower. Of the 3 components of the model, valence of job outcomes was by far the best single predictor. Support was given to 1 of the 2 multiplicative relationships posited by the model. Implications for future testing of expectancy-valence models with survey methodology are discussed, especially for the measurement of instrumentality. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The potential role of lycopene for human health

Lycopene is one of the major carotenoids in Western diets and is found almost exclusively in tomatoes and tomato products. It accounts for about 50% of carotenoids in human serum. Among the common dietary carotenoids lycopene has the highest singlet oxygen quenching capacity in vitro. Other outstanding features are its high concentration in testes, adrenal gland and prostate. In contrast to other carotenoids its serum values are not regularly reduced by smoking or alcohol consumption but by increasing age. Remarkable inverse relationships between lycopene intake or serum values and risk have been observed in particular for cancers of the prostate, pancreas and to a certain extent of the stomach. In some of the studies lycopene was the only carotenoid associated with risk reduction. Its role in cancer risk reduction still needs to be clarified. Patients with HIV infection, inflammatory diseases and hyperlipidemia with and without lipid lowering treatment may have depleted lycopene serum concentrations. Before embarking on large-scale human trials the distribution of lycopene and its biological functions need to be further evaluated.     

Noise and intellectual performance: a confirmation and extension

To confirm and extend the results of a previous investigation by the author (1974), 29 college students performed a proofreading task in quiet and in a moderate level of noise consisting of a tape recording of radio news items. Corroborating earlier findings, it was found that (a) noise significantly impaired the detection of grammatical errors ( p     

Noise and driver performance.

The demands of actual automobile driving and concurrent noise stress on human information-processing capacity for 8 licensed, college-aged drivers were estimated from the decrement in performance on the delayed digit recall subsidiary task, using multivariate techniques and a counterbalanced design. Under high load, drivers were much more likely to reduce accuracy than sacrifice speed; however, noise did not result in driving error when presented in the absence of additional load. This conclusion parallels the 1973 findings of H. Moscowitz, who investigated the effect of alcohol on driving performance. As expected, the subsidiary task measure was sensitive to the additional information-processing demands imposed by the unpredictable noise stimulus; but contrary to expectation, inclusion of the subsidiary task tended to interact slightly with noise in impairing driving performance. It is suggested that perhaps in the low-risk driving environment, maintenance of performance on the subsidiary task may have had sufficiently high subjective utility to demand a disproportionately large share of information-processing capacity. (20 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Mere effort and stereotype threat performance effects.

Although the fact that stereotype threat impacts performance is well established, the underlying process(es) is(are) not clear. Recently, T. Schmader and M. Johns (2003) argued for a working memory interference account, which proposes that performance suffers because cognitive resources are expended on processing information associated with negative stereotypes. The antisaccade task provides a vehicle to test this account because optimal performance requires working memory resources to inhibit the tendency to look at an irrelevant, peripheral cue (the prepotent response) and to generate volitional saccades to the target. If stereotype threat occupies working memory resources, then the ability to inhibit the prepotent response and to launch volitional saccades will be impaired, and performance will suffer. In contrast, S. Harkins's (2006) mere effort account argues that stereotype threat participants are motivated to perform well, which potentiates the prepotent response, but also leads to efforts to counter this tendency if participants recognize that the response is incorrect, know the correct response, and have the opportunity to make it. Results from 4 experiments support the mere effort but not the working memory interference account. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Relationship between measures of effort and job performance.

Effort expended and job performance are considered to be different, although not independent, constructs in the industrial environment. The relationship between these 2 variables was investigated using the multitrait-multimethod and multitrait-multirater approaches. 202 engineers completed self-ratings and were rated by their supervisors (n = 41), using global and dimensional rating methods. Convergent validity was found for the measures of effort and the measures of performance, but only the measures of performance demonstrated discriminant validity when compared with the measures of effort. Raters demonstrated convergent validity for each variable, but only some discriminant validity on the performance measures. Implications of the results are discussed in terms of appropriateness of the dimensional measure of effort. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Expectancy theory predictions of academic effort and performance.

Used expectancy theory models to predict the academic effort and performance of 60 male undergraduates. Rating scales completed by Ss support the theory that effort is related to the degree to which the behavior (or job) is seen as leading to various outcomes weighted (multiplicatively) by the evaluation of these outcomes. The predictability of effort increased when extensions of the effort model were included by adding others' expectations and perceived influence. Ss' self-reports of effort and GPA and college entrance exam records were used to test the job performance model, which suggests that effort and ability combine to predict performance. Neither the additive nor the multiplicative models found support in this setting. The extensions and modifications of the theory are discussed in detail. (17 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Normal aging and human physiology

This article discusses the physiological changes that accompany normal aging and current understandings of how environmental factors interact with a person's genetic mechanisms to slow or speed up the aging process. Chronological age is contrasted with biological age to illustrate the different rates and extent of anatomical changes and functional declines observed in older people of the same age, behaviors that appear to delay or reduce the inevitable progression of sensescence, the extraordinary heterogeneity of the aging population, and the complexity of the processes responsible for the consequences of human aging.     

Impact of group goals, task component complexity, effort, and planning on group performance.

Tested a model asserting that goal difficulty and task component complexity influence group performance by affecting the effort exerted by group members, the amount and quality of their planning, and the timing of their planning (preplanning vs in-process planning). Hypotheses derived from this model were tested in a 2?×?2 experimental design. 56 groups of 4 students each worked for 15 min building Tinkertoy structures. Results show that group-goal difficulty influenced group performance through effort; task component complexity influenced performance through the amount of planning performed by group members and the level of effort invested in their work; and the quality of the group's planning process also influenced group performance. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Priming of human neutrophils by peroxynitrite: potential role in enhancement of the local inflammatory response

The antimicrobial activity of a new super-oxidized water, Sterilox, has been tested against Mycobacterium tuberculosis, Mycobacterium avium-intracellulare, Mycobacterium chelonae, Escherichia coli (including type O157), Enterococcus faecalis, Pseudomonas aeruginosa, Bacillus subtilis var niger spores, methicillin-resistant Staphylococcus aureus, Candida albicans, poliovirus type 2 and human immunodeficiency virus HIV-1. Under clean conditions, freshly generated Sterilox was found to be highly active against all these micro-organisms giving a 5 log10 (99.999%) or greater reduction in two minutes or less.     

A new look at psychological climate and its relationship to job involvement, effort, and performance

This study investigated the process by which employee perceptions of the organizational environment are related to job involvement, effort, and performance. The researchers developed an operational definition of psychological climate that was based on how employees perceive aspects of the organizational environment and interpret them in relation to their own well-being. Perceived psychological climate was then related to job involvement, effort, and performance in a path-analytic framework. Results showed that perceptions of a motivating and involving psychological climate were related to job involvement, which in turn was related to effort. Effort was also related to work performance. Results revealed that a modest but statistically significant effect of job involvement on performance became nonsignificant when effort was inserted into the model, indicating the mediating effect of effort on the relationship. The results cross-validated well across 2 samples of outside salespeople, indicating that relationships are generalizable across these different sales contexts.     

Job characteristics, flow, and performance: The moderating role of conscientiousness.

The present article aims to show the importance of positive work-related experiences within occupational health psychology by examining the relationship between flow at work (i.e., absorption, work enjoyment, and intrinsic work motivation) and job performance. On the basis of the literature, it was hypothesized that (a) motivating job characteristics are positively related to flow at work and (b) conscientiousness moderates the relationship between flow and other ratings of (in-role and out-of-role) performance. The hypotheses were tested on a sample of 113 employees from several occupations. Results of moderated structural equation modeling analyses generally supported the hypotheses. Motivating job characteristics were predictive of flow, and flow predicted in-role and extra-role performance, for only conscientious employees. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Noise and the young mouse: Genotype modifies the sensitive period for effects on cochlear physiology and audiogenic seizures.

Examined the correspondence between the critical period, during which acoustic trauma will profoundly alter subsequent auditory behavior, and the broader sensitive period, during which acoustic trauma is most damaging to cochlear functions in the young ear, using 133 C57BL/6 and 183 CBA mice (aged 12–54 days) as Ss. Ss were exposed to 2 min of 124-db octave band noise (8–26 kHz). A noninvasive electrocochleographic technique was used to assess cochlear microphonic (CM) and action potential (AP) thresholds in exposed Ss and nonexposed littermate controls. Noise had no effect on 12-day-old CBA Ss but produced a maximal threshold elevation at 30–36 days in 54-day-old Ss. Susceptibility to audiogenic seizures in exposed CBA Ss was greatest at the peak of the sensitive period for cochlear damage. 12-day-old C57BL/6 Ss were also unaffected by noise exposure; 36-day-old C57BL/6 Ss had maximal AP (23 db) and CM (17 db) threshold; elevations and 54-day-old C57BL/6 Ss had an 18-db elevation of the AP; and their CM was no longer affected. It is concluded that both genotypes have a sensitive period for the effects of noise trauma on CM and AP thresholds: CBA has a sensitive period for acoustic priming for audiogenic seizures, and C57BL/6 has a critical period for acoustic priming. (48 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Mothers' beliefs about the role of ability and effort in school learning.

Over 500 mothers of children in kindergarten through fifth grade were surveyed. Mothers' preferences for mastery versus performance-based achievement goals were differentiated in terms of the priority mothers gave to the demonstration of effort versus high performance as desired student outcomes. The findings showed that mothers' views about the nature of learning in schools can be differentiated according to their achievement goal emphasis. Mastery and performance goals involved different beliefs about how learning occurs, how it is fostered, how it is evidenced, and how it should be evaluated. The findings suggest that children of mothers with different achievement goals may be encouraged to pursue different types of achievement activities, may be evaluated on different aspects of their behavior, and may experience different types of expectations. (PsycINFO Database Record (c) 2010 APA, all rights reserved)