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Showing 4 results for Cognitive Performance

Zohreh Mohebian, Habibollah Dehghan, Ehsanollah Habibi,
Volume 7, Issue 3 (9-2017)
Abstract

Introduction: Heat stress is one of the Hazardous physical agents in the workplace, which can cause impairment of cognitive performance. The current study aimed to evaluate the effect of different levels of heat stress on attention and reaction time in a laboratory condition.

Material and Method: This experimental study was done among 33 students included 17 males and 16 females. Mean age of the participants was 22.1(SD=2.3). Attention and reaction time parameters were evaluated using the continuous performance test and  reaction time measurement device respectivlely, after exposure to different heat levels (22°C and 37°C). Data were analyzed using ANOVA test and SPSS 20 software.  

Result: The results of tests attention and reaction time showed that the average of attention percentage was decreased and the average of reaction time increased by increasing the heat level, with a  statistical differences of  (P˂0.001) in both cases. Attention percent in terms of exposure to 22°C temperature was significantly higher than 37°C (P˂0.001). But, reaction time was significantly higher than with the exposure to 37°C temperature than 22°C (P˂0.001).

Conclusion: The results of this study showed that, heat by increasing reaction time and decreasing attention leading to an impairment  in the individual’s cognitive performances. Therefore, in jobs such as control rooms and various industries that need attention, concentration and quick reaction, it is necessary to consider and optimize the heat conditions in order to increase the level of attention and decrease of reaction time.


Taleb Askaripoor, Majid Motamedzade, Rostam Golmohammadi, Mohammad Babamiri, Maryam Farhadian, Hamed Aghaei, Mohammad Ebrahim Ghaffari, Elahe Kazemi, Mehdi Samavati,
Volume 11, Issue 4 (12-2021)
Abstract

Introduction: Recent evidence indicates that lighting can affect physiological and neurobehavioral human functions, referred to as non-image forming (NIF) effects of lighteffects. This study aimed to determine the effects of illumination levels and correlated color temperature (CCT) on alertness and performance under NIF conditions.
Material and Methods: In this study, 22 participants were exposed to light at various levels of illumination, including very low illuminance (<5 lux, control) and light conditions with correlated color temperatures (CCT) of 4000 K, 8000 K, and 12000 K at 300 and 500 lux. The data collection process included recording the power of brainwaves (alpha, alpha-theta, beta, and theta), sleepiness and mood scales, and cognitive performance tests for sustained attention, psychomotor vigilance task (PVT), working memory, and inhibitory capacity.
Results: The results indicated that 500 lux light conditions at correlated color temperatures of 8000 and 12000K significantly reduced normalized alpha, alpha-theta power, subjective sleepiness, and performance compared to the dim light condition. Under illumination levels of 300 and 500 lux, there were no significant differences in the measured values of the variables.
Conclusion: Lighting interventions can be used as a supplement to other strategies for increasing alertness and performance in the workplace.
Azar Mehrabi Matin, Mahsa Alefi, Mohammad Reza Monazzam, Adel Mazloumi, Kamal Azam,
Volume 12, Issue 1 (3-2022)
Abstract

Introduction: The noise could affect some aspects of human health, including the cognitive performance. In addition to sound pressure level and exposure time, the psychoacoustic features of noise may cause destructive effects on humans. A few recent studies have been conducted on effect of sound quality on cognitive performance. This study aims to find the noise loudness and sharpness levels as the most destructive effects on human cognitive performance.
Material and Methods: This was a cross-sectional study on 10 male students of Tehran University of Medical Sciences. The Noises were generated in two channels that the left channel produced the pink noise as a background noise. The pink noise loudness and sharpness were 19.7 sone and 2.49 acum, respectively. The right channel generated noises with different loudness and sharpness levels the noise loudness ranged from 8.87 to 67.9 sone and the noise sharpness ranged from 1.07 to 6.4 acum. Finally, ten noises with different loudness and sharpness were applied. The students were exposed to ten different types of noise and a silent condition. The Mathematical Problem Solving Task (MPST) test was performed to assess cognitive performance. The reaction time and the accuracy rate were measured after 5 minutes of noise exposure. Data were analyzed by SPSS (ver. 22). P< 0.05 was considered as significant level.
Results: The mean reaction time and the mean accuracy rate increased with the sharpness level.  However, alteration in the loudness and sharpness levels had no significant effect on the speed and accuracy of students. Performance speed increased in noise 3 with the highest loudness (L=67.9, SH=1.07) in comparison with the silent condition (p-value=0.05). The mean accuracy rate in exposure to the noise 9 reduced in comparison with silence (p-value=0.04)
Conclusion: Different levels of psychoacoustic features had no significant effect on the cognitive performance parameters. Although, the accuracy rate and the reaction time decreased in noises 9, the sharpest noise, and 3, the loudest noise, in comparison to the silence, respectively.
Zahra Ghanbari, Seyed Abolfazl Zakerian, Alireza Choobineh, Mohammad Nami, Faramarz Gharagozlou,
Volume 12, Issue 4 (12-2022)
Abstract

Introduction: Cognitive emotion regulation (CER) strategies define as cognition-based responses according to emotion-eliciting experiences that can change the type and severity of individuals’ reactions and behaviors. This modification may positively or negatively affect cognitive performance and therefore, it is a defining issue in the workplace. Notably, industries such as combined cycle power plants need to hire staff with a high cognitive ability to perform their duties in a highly efficient way. Since CER is of great importance for overall health and cognitive performance, we aimed to evaluate the state of CER among control room operators (CROs) in the Fars combined cycle power plant.
Material and Methods: The CER questionnaire (CERQ) measures nine cognitive coping strategies (i.e., self-blame, other-blame, rumination, catastrophizing, positive refocusing, planning, positive reappraisal, putting into perspective, and acceptance) that are followed when an individual confronts negative events. The CERQ (short version) was administered to 57 male CROs at the Fars combined cycle power plant. The questionnaire also collected demographic data. Statistical analyses were performed using SPSS Version 25.0. For the normality test, Shapiro-Wilk was the method of choice.
Results: Results of the CERQ scoring showed that the median with interquartile range (IQR) in appropriate and inappropriate categories were 3.50 (3.30-4.00) and 2.62 (2.25-3.06), respectively. Of note, age (39.07 ±6.19) and work experience (14.49±6.26) were not significantly correlated with the results of CERQ.
Conclusion: Taken together, adaptive cognitive strategies (acceptance, positive refocusing, planning, positive reappraisal, and putting into perspective) were reported to be used more often than less adaptive strategies. In general, staff strategies were appropriate while facing a negative event. Although assessing CER in high-demand workplaces is necessary, factors such as managerial styles, job engagement, job satisfaction, and larger sample size should be further studied.

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