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Biomedical subjects

S R Tripathi

Publications and source records attributed to S R Tripathi.

13 recordsLinked to original sources
PubMed1997

Interaction of Illumination with noise on neuropsychological performance capability.

To determine the interaction effect of illumination with noise performance data were recorded from 20 male college student volunteers on a battery of neuropsychological tests comprising 'memory and search,' 'name and number checking,' 'Flanagan's eye-hand coordination' and 'digit symbol.' Each subject worked under two of the four combinations of illumination (low, 300 lux; high, 500 lux) with quiet (60 dBA) and noise (100 dBA) conditions. A 2 x 2 analysis of variance was performed on the test scores. The accuracy of performance was found enhanced by high illumination in all the tests, but the speed of performance was impaired by noise. The interaction effect was significant, indicating the speed and efficiency of performance increasing while the accuracy of performance affected differently with high illumination under noise condition. However, the error of performance increased by noise under high illumination. Further investigation on a range of neuropsychological tests is suggested before the conclusions are drawn more firmly.

Adult↗
PubMed1995

Neurobehavioural changes in workshop painters of a public transport network.

To determine alterations in functional capacities due to exposure to solvents in painters, a battery of psychological tests consisting of associative recall, critical flicker fusion, letter cancellation, Muller-Lyer illusion and card sorting was administered before their work day schedule starting at 0800 h, 16 h after cessation of their work the previous day. Simultaneously a reference group of diesel worker and a control group were also tested at the same time of day. Age-adjusted performance scores were calculated for the painter group and diesel worker group based on the linear age trend of the control group. Analysis of variance suggested significant degradation in performance on tests of critical flicker fusion (alternate), letter cancellation, Muller-Lyer illusion and card sorting (by design configuration). Persistence of solvent exposure effects through visual and motor function impairments is reflected.

Adult↗
PubMed1993

Assessment of comfort of various hearing protection devices (HPD).

To evaluate the comfort of hearing protection devices, two models of ear plugs and five models of ear muffs were tested. The psychophysical method of 'single stimuli' was applied on a group of 30 subjects with or without wearing the devices for a short duration of 15 min under noise condition of 100 dBa in the acoustic chamber as also on a group of 10 weavers with the protection devices worn for longer durations of 1 h, 4 h and 8 h under noise exposure of 102-104 dBA in the weaving shed. Each subject performed 8 trials with each type of device on different days. Application force and tightness of spring were also evaluated. The results yielded a comfort grading for hearing protection devices. The comfort grading, however, depended on several factors in addition to application force and tightness of spring, which has been discussed.

Adult↗
PubMed1991

Human performance capability in psychomotor tasks at variable difficulty levels and physiological reactions under noise and heat conditions.

The effects of noise and heat on the efficiency of human performance of psychomotor tasks at variable difficulty levels were investigated. Twenty four young, healthy volunteers with normal hearing, randomly divided into 4 equal sized groups, were tested in a climatic chamber under 4 combinations of two environmental conditions made up of noise and heat, each at two levels: 70 dB (A) (quiet), 100 dB (A) (noise): 28 degrees C (comfortable), 35 degrees C (heat). A statistically balanced procedure was followed. Three physiological variables were also recorded: Heart rate, blood pressure and body temperature. A 2 x 2 analysis of variance showed rise in the physiological variables by noise and heat respectively as well as by their interactions. Performances of the psychomotor tasks were affected differently by noise and heat depending on the difficulty levels of the tasks. The interaction of noise and heat entailed superior performance of the tasks of memory and search, two hand coordination and reaction time, at moderate difficulty levels, but no distinct interaction effect was observed on the performance of tweezer dexterity.

Adult↗
PubMed1990

Acute effects of heat on neuropsychological changes and physiological responses under noise condition.

To examine the effects of heat and noise individually and jointly on certain physiological responses and cognitive and neuromotor based functions, 12 male participants were tested under 6 experimental conditions which resulted by combining 3 levels of heat (25 degrees, 30 degrees and 35 degrees C) and 2 levels of white noise (70 and 100 dB). The experiment was carried out in a controlled climatic chamber following two 6 x 6 latin square designs. The results indicated elevations in heart rate, oxygen uptake and body temperature due to the independent effect of heat or the combined effects of heat and noise. The independent action of noise was found to be depressive on the first two responses. On the neuropsychological effects, the heat adversely affected the speed in card sorting (by design configuration) and digit symbol tests, and also the accuracy and error rate in the reasoning ability test. The noise caused performance improvements in critical flicker frequency (simultaneous) and in error rates in card sorting (by design configuration). The combined effects of heat and noise indicated higher error rates in card sorting (by face value), decreased accuracy in reasoning ability and improvements in performance in accuracy scores and error rates in digit symbol test.

Adult↗
PubMed1989

The effects of times of day on cognitive and visuo-motor performance efficiency.

Twenty-four male graduate volunteers were administered a battery of psychological tests--critical flicker fusion (CFF; alternate and simultaneous), reaction time (simple and choice), memory (forward and backward), and associative recall--to ascertain their performance capability during the different times of day. Each subject performed the tests on two occasions, once in the morning (10:00 h) and on the second occasion in the evening (15:00 h), on two successive days, following a statistically balanced design. Analysis of variance reflected superior performance on reaction time (choice) and memory (backward) in the evening and on associative recall in the morning. While no such effects were noticeable on CFF, appreciable changes in performance with the decreasing brightness level of its light sources was observed. Further work in this direction on a variety of cognitive tests and sensory functions under various times (more than two times) throughout the day is suggested.

Adult↗
PubMed1989

The combined effects of noise and illumination on the performance efficiency of visual search and neuromotor task components.

A battery of performance tests consisting of 'letter cancellation,' 'hand 'precision,' 'two-hand coordination,' and 'tweezer dexterity' were administered on 12 desk workers in an illumination chamber under six different combinations of noise and illumination made out of two levels of white noise (70 and 100 dB) and three levels of illuminations (50, 150, and 300 lx). The objective was to find out the combined effects of noise and illumination on the performance efficiency of the above tests. A 6 x 6 latin square design was followed. A three-way analysis of variance reflected significant combined effects of noise and illumination on the accuracy scores of the letter cancellation test and hand precision test and the efficiency score of the latter test. Significant separate effects of noise were, however, observable on the speed scores and efficiency scores of the letter cancellation test and that of illumination on the speed scores of this test as also the accuracy scores of the tweezer dexterity test. Studies ascertaining the effects of heat stress in combination with noise and illumination on human performance efficiency have been suggested.

Adult↗
PubMed1989

Neurobehavioural disturbances in workers engaged in high-pressure spray painting.

A battery of neurobehavioural tests consisting of reaction time (simple and choice), tweezer dexterity, hand precision, and memory (forward and backward) were administered to a group of painters before and after their work schedule to provide a quantitative assessment of the possible behavioural changes. Their responses on five affective measures, e.g., headache, mental freshness, forgetfulness, sleepiness, and general good health were also collected on visual analogue scales. Analysis of variance indicated significant deterioration of performance on reaction time (choice), tweezer dexterity (accuracy), hand precision (accuracy), and memory (backward) in the painters by the end of their work-shift. Significant deleterious effects were also noted on headache, mental freshness, and sleepiness. The degree of deterioration of their performance on these tests as also of the affective measures were found to be associated with the duration of exposure.

Adult↗
PubMed1989

Evaluation of lighting conditions in relation to visual comfort in workplaces of weavers in a textile mill.

The present investigation was undertaken to examine the lighting conditions in a weaving shed and also to assess visual comfort of the weavers and their visual preferences to the lighting levels. A light meter was used for measurement of the illuminances. Comfort vote cards and preference vote cards were administered on almost all the weavers (N = 95). The results indicated that the illumination levels were very low compared to the Indian Standard (1966) or IES standard (1973). A substantial proportion of the weavers had no visual comfort at work and expressed their preferences for higher illumination levels for comfort, safety, and optimum work performance. The results have been discussed and appropriate measures have been suggested for improved lighting in a cost-effective manner.

Adult↗