WHO Neurobehavioral Core Test Battery Research Articles

Preliminary Study on Student’s Performance and Thermal Comfort in Classroom

In Malaysia, students spend up to 33% of their day in classrooms and school buildings. Previous research had shown that thermal comfort conditions in educational buildings can stimulate student productivity. This study aimed to preliminary investigate the relationship between thermal sensation and student performance in the classroom. Data collection was conducted in a selected classroom at a secondary school in Segamat, Johor. All data were collected for three days. Physical measurement data were taken using thermal comfort equipment, KIMO AMI 310 for indoor measurement (air temperature, mean radiant temperature, air velocity, relative humidity), and TSI VelociCalc for outdoor measurement (air temperature, relative humidity). The thermal comfort satisfaction questionnaire was distributed to 36 students in the classroom. The learning performance was assessed through a simple reaction test and digit span test based on the WHO Neurobehavioral Core Test Battery (NCTB) method. The results of the thermal comfort satisfaction questionnaire clearly showed that the lower the fan speed, the more students preferred the cooler option. Furthermore, students performed better when the fan speed was increased. Based on the correlation analysis, it can be concluded that the learning performance and thermal preference vote (TPV) are positively correlated. As a result, students tend to get higher scores when they feel cooler. This study provides important preliminary information on classroom conditions in secondary schools in Malaysia and provides a better understanding of the relationship between thermal perception and student learning performance in the classroom.

Influence of Air Velocity on Thermal Comfort and Performance of Students in Naturally Ventilated Classrooms in Tropical Climate

Air velocity is among the most important factors influencing thermal comfort in naturally ventilated spaces in hot and humid tropical climates. It is important to have air velocity that suits comfort needs and enhances the student's learning performance in the classroom, especially in schools that rely only on natural ventilation assisted by ceiling fans. In this study, the thermal comfort and learning performance of students in a selected naturally ventilated classroom at a secondary school in Segamat, Johor, Malaysia, were experimentally evaluated under different air velocity conditions during the peak temperature period during the school session. Throughout the experiment, physical measurement and a subjective evaluation questionnaire were conducted for thermal comfort analysis and to gather the student’s thermal environment evaluation in the classroom. Students’ learning performance was assessed through simple reaction and digit span tests based on the WHO Neurobehavioral Core Test Battery (NCTB). All the assessment results were statistically analyzed, and the relationships among indoor air velocity, thermal comfort, and learning performance were obtained. The result showed optimal learning performance was significant when students felt “slightly cool” and air velocity was more than 0.95 m/s. Hotter environments and a lack of air movement were found to be causes of declining student performance. In conclusion, it is suggested that the comfort zone in a naturally ventilated classroom for school students should be set within the range of -1 (slightly cool) with an air velocity greater than 0.76 m/s.

Pilot Study on Investigation of Thermal Sensation Votes (TSV) and Students' Performance in Naturally Ventilated Classroom

Thermal comfort is essential for students' wellbeing, health, and performance. A conducive classroom must consider the acceptable range of heat and its impact on student performance. The study aims to conduct a pilot test for the determination of thermal acceptability and student performance in existing Malaysian classrooms using physical and subjective assessments. The methodology requires physical measurement using KIMO AMI 310 instrument, as well as subjective assessment via satisfaction survey adapted from ASHRAE 55 and performance assessment adapted from WHO Neurobehavioral Core Test Battery (WHO NCTB). Physical measurement parameters, such as indoor temperature, air velocity, relative humidity, and prevailing mean outdoor temperature, were measured in parallel with subjective assessment of thermal acceptability and performance assessment. Three days of data collection were conducted in the secondary school located in Endau, Johor. There are three classes involved with a total of 46 students. Each class was equipped with two ceiling fans and both ceiling fans were regulated to the speed of four. The overall physical and subjective assessment procedure took approximately 60 minutes per classroom. The findings showed that all the investigated classes were in the range of acceptable operative temperature and complied with ASHRAE Standard 55 for both 80% and 90% acceptability limits. Pearson correlation analysis showed a small positive relationship between thermal sensation vote (TSV) and learning performance was obtained. The results also showed a higher performance score at the TSV value of -1 suggesting the students tend to have higher performance scores when they voted feeling slightly cool. Thus, the results of the pilot test gave new insight into the effective method to improve the methodology for the actual data collection.

Association between pesticide exposure and neurobehavioral performance of agricultural workers: A cross-sectional study.

BackgroundPesticide exposure has affected humans’ health, especially those directly in contact with a pesticide like agricultural workers. Here, we sought to see a link between pesticide exposure and cognitive impairment among male agricultural workers.MethodsWe selected 18–60 years old 100 male agricultural workers who came for their health check‐up in the hospital's out‐patient department from August 2020 to May 2021. Standardized questionnaires (German Q18 questionnaire) and WHO Neurobehavioral Core Test Battery were used to examine the neurobehavioral performance of the individuals. The data were presented in a descriptive manner and statistically examined using the chi‐square test.ResultsThe male agricultural workers’ neurobehavioral performance was 46% normal and 54% abnormal. Headaches, impaired focus, short memory, weariness, palpitation, and numbness were the most prevalent neurobehavioral impairments. The chi‐square test revealed that spraying frequency (p =.010), personal protective equipment (PPE) use (p < .001), and smoking habits (p =.006) were all linked to neurobehavioral performance, while spraying duration (p =.804), working years (p =.234), pesticide types (p =.816), and spraying time (p =.867) were not linked to neurobehavioral performance.ConclusionWe found that pesticide exposure has a certain role on neurobehavioral performance in adult male agricultural workers as more people have been affected; however, a considerable number of confounding factors might have played a significant role in giving rise to such results. The government should be concerned about farmer's neurobehavioral performance and implement different approaches to minimize the use of pesticides so that agricultural workers can work without any mental health problems.

Neurobehavioral performance of Indonesian farmers and its association with pesticide exposure: A cross-sectional study

BackgroundAcute and chronic pesticide exposure affect human health. The study aimed to assess the neurobehavioral performance and its association with pesticide exposure factors among Indonesian farmers. MethodsA cross-sectional study was conducted among farmers living in Jember, Indonesia. Basic individual characteristics and pesticide exposure factors were documented using questionnaire-based interviews. The neurobehavioral performance was assessed by the German Q18 questionnaire and the WHO Neurobehavioral Core Test Battery (NCTB) consists of the Digit Span, Digit Symbol, Pursuit Aiming, and Trail making instruments. Data were presented descriptively and analyzed statistically using the chi-square test. ResultsAs many as 90 farmers were recruited. Most farmers were 45–55 years old and had a normal nutritional status and moderate smokers. The neurobehavioral performance of the farmers was 62.22% normal and 37.78% abnormal. The most common neurobehavioral deficits were short memory, concentration difficulties, excessive fatigue, frequent headache, and tremor. The chi-square test showed that the spraying frequency (p = 0.006), the spraying duration (p = 0.002), the working years (p = 0.013), and the PPE usage (p = 0.022) associated with neurobehavioral performance, but the pesticide types (p = 0.289) and spraying time (p = 0.627) did not associated with neurobehavioral performance. ConclusionAlthough most farmers showed a normal neurobehavioral performance, some pesticide exposure factors demonstrated an association with neurobehavioral performance among Indonesian farmers. Multiple approaches including implementation of the regulation, choosing alternative biopesticides, and regular counseling on all aspects of pesticides, their impact on health are recommended to minimize pesticides' negative effects.

BLOOD LEAD CONCENTRATIONS AND THE NEUROPSYCHOLOGY SCORES OF PREGNANT WOMEN IN KLANG VALLEY, MALAYSIA

Pregnant women with high blood lead posed high risk to their fetus as placental transfer can occurs to the fetus. The objective of this study was to identify the relationship between blood lead and the neuropsychological score of women who were in their 3rd trimester of pregnancy. These respondents were undergoing a routine antenatal checkup at a teaching hospital located in Klang Valley areas. Blood lead concentrations were analyzed using graphite furnace Atomic Absorption Spectrophotometer (AAS). The neuropsychological scores were measured with WHO Neurobehavioral Core Test battery (NCTB). The test consists of 7 items, which made up of the Digit Symbol, Trail Making, Digit Span, Benton Visual Retention Test, Pursuit Aiming, Santa Ana Manual Dexterity, Reaction Time and Movement Time tests. The mean blood lead was 7.78±4.77 µg/dL. The mean score for the total NCTB test was 50.00±5.24. Statistical analysis showed blood lead concentrations were inversely correlated with the total NCTB score (r= –0.462, p≤0.01). The correlation was about 21.3%. The General Linear Model (GLM) showed that age (β= –0.15, p=0.017), weight (β=2.67, p=0.05) and height (β=–1.97, p=0.05) also influence the total neuropsychological scores. In conclusion, blood lead reduces the total neuropsychological scores. The scores for each of the 7 items were inversely and significantly correlated with blood lead concentrations except for the Trail Making and Santa Ana Manual Dexterity tests.

Neurobehavioral effects of arsenic exposure among secondary school children in the Kandal Province, Cambodia

The research was carried out at 3 study sites with varying groundwater arsenic (As) levels in the Kandal Province of Cambodia. Kampong Kong Commune was chosen as a highly contaminated site (300–500μg/L), Svay Romiet Commune was chosen as a moderately contaminated site (50–300μg/L) and Anlong Romiet Commune was chosen as a control site. Neurobehavioral tests on the 3 exposure groups were conducted using a modified WHO neurobehavioral core test battery. Seven neurobehavioral tests including digit symbol, digit span, Santa Ana manual dexterity, Benton visual retention, pursuit aiming, trail making and simple reaction time were applied. Children's hair samples were also collected to investigate the influence of hair As levels on the neurobehavioral test scores. The results from the inductively coupled plasma-mass spectrometry (ICP-MS) analyses of hair samples showed that hair As levels at the 3 study sites were significantly different (p<0.001), whereby hair samples from the highly contaminated site (n=157) had a median hair As level of 0.93μg/g, while the moderately contaminated site (n=151) had a median hair As level of 0.22μg/g, and the control site (n=214) had a median hair As level of 0.08μg/g. There were significant differences among the 3 study sites for all the neurobehavioral tests scores, except for digit span (backward) test. Multiple linear regression clearly shows a positive significant influence of hair As levels on all the neurobehavioral test scores, except for digit span (backward) test, after controlling for hair lead (Pb), manganese (Mn) and cadmium (Cd). Children with high hair As levels experienced 1.57–4.67 times greater risk of having lower neurobehavioral test scores compared to those with low hair As levels, after adjusting for hair Pb, Mn and Cd levels and BMI status. In conclusion, arsenic-exposed school children from the Kandal Province of Cambodia with a median hair As level of 0.93µg/g among those from the highly contaminated study site, showed clear evidence of neurobehavioral effects.

Reconsideration of the WHO NCTB strategy and test selection

The World Health Organization-recommended neurobehavioral core test battery (NCTB) became the international standard for identifying adverse human behavioral effects due to neurotoxic chemical exposure when it was first proposed in 1983. Since then the WHO NCTB has been repeatedly cited as the basis for test selection in human neurotoxicology research. A discussion group was held before the International Symposium on Neurobehavioral Methods and Effects in Occupational and Environmental Health to review the NCTB and reconsider its tests. The workshop made three consensus recommendations to the International Congress on Occupational Health (ICOH) Scientific Committee on Neurotoxicology and Psychophysiology (SCNP):.1.A ‘screening’ battery of broadly sensitive tests is needed as guidance to the field of human neurotoxicology2.The SCNP should convene a panel to reconsider the functions measured and the tests in the WHO NCTB3.Three disciplines should be represented in the panel recommending a revised NCTB: neuropsychology; experimental psychology; neurologyThis recommendation will be pursued at the next meeting of the International Congress on Occupational Health (ICOH) Scientific Committee on Neurotoxicology and Psychophysiology (SCNP).

Psychological and cognitive impairment of long-term migrators to high altitudes and the relationship to physiological and biochemical changes.

The present study aimed to examine how long-term migration to high-altitude regions affects mentality and cognition, and the correlation with various physiological and biochemical changes. The WHO Neurobehavioral Core Test Battery, Raven's Standard Progressive Matrices (RSPM) and Pittsburgh Sleep Quality Index questionnaire were used to assess 141 young male subjects who lived in plain regions and 217 young male subjects who had migrated to a 4500 m high-altitude region and lived there for 1-5 years. Arterial oxyhemoglobin saturation, cerebral tissue oxygenation indices (TOIs), serum S100B and brain-derived neurotrophic factor (BDNF) were also measured. Long-term migrators to a high-altitude region exhibited exacerbated mood disorders, retarded color discrimination ability, decreased visual memory capacity, and impaired perceptual motor skill and motion stability. In addition, the migrators exhibited lower RSPM scores and lower sleep quality. Further analyses revealed significant correlations between sleep quality and cerebral TOIs, mood and sleep quality, mood and certain cognitive functions, mood and serum BDNF levels, and RSPM scores and serum S100B levels. Long-term living at high altitudes causes significant impairment of psychological and cognitive function. Cerebral hypoxic extent, sleep quality and biochemical dysfunction are major influencing factors.

Follow-up Study on Occupational Exposure to Organic Solvents and Neurobehavioral Performances of Automotive Painters

Background/Aims: This study assessed occupational exposure to organic solvents and neurobehavioral performance of exposed automotive painters. The mean personal air toluene concentration (PATC), urinary hippuric acid concentration, and standard score (SS) of the modified WHO Neurobehavioral Core Test Battery (NCTB) of exposed workers in 2008 were compared with those obtained in 2004. Methods: The study subjects consisted of 48 automotive painters who had participated in the 2004 study. They were re-examined in 2008 using PATC, urinary hippuric acid concentration, and 7 test items of the NCTB. A questionnaire was used to obtain sociodemographic information. Results: The mean PATC in 2008 was 0.403 ppm, which was significantly lower (P < 0.001). The mean SS for the Digit Span Test, Benton Visual Retention Test, Pursuit Aiming Test, and Total NCTB were significantly higher in 2008 compared to those in 2004 with the exception of the Santa Ana Manual Dexterity Test that showed significantly lower mean SS in 2008 compared to those in 2004. Conclusion: The lower concentration of solvents in the workplace and a shorter duration of exposure have contributed toward an improvement in the neurobehavioral performance of automotive painters in 2008 as compared to those in 2004 with the exception of manual dexterity.

Emotional and Neurobehavioural Status in Chronic Pain Patients

To investigate the emotional and neurobehavioural status of patients suffering from chronic pain. Fifteen male patients with chronic lower back pain and 15 healthy control subjects were studied for approximately six months. Pain was measured using a visual analogue scale. The WHO Neurobehavioral Core Test Battery (NCTB) was used to assess neurobehavioural effects of environmental and occupational exposures. Visual analogue scale results demonstrated a modest range of reported pain (mean [± SD] 62.0 ± 10.8) in chronic pain patients, whereas control subjects reported no measurable pain. With the NCTB, it was found that scores of negative mood state, including anger-hostility, depression-dejection, fatigue-inertia and tension-anxiety in pain patients were significantly higher than scores in the control subjects. By contrast, scores of positive mood state (vigour-activity) in chronic pain patients were lower than those in the control group. The NCTB scores of the Santa Ana Dexterity and Pursuit Aiming II tests in chronic lower back pain patients were lower than those of the control group. Scores for other NCTB subtests, including the Digit Span, Benton Visual Retention and Digit Symbol tests, were not significantly different compared with controls. <span style="font-weight: Chronic lower back pain patients had more negative mood and less positive mood than controls. These patients also demonstrated neuromotor deficits in coordination and reaction time. Further studies are required to examine possible neurological mechanisms and research potential intervention strategies for patients suffering from chronic pain.

THE INFLUENCE OF BLOOD LEAD ON THE NEUROPSYCHOLOGY OF PREGNANT WOMEN IN THE KLANG VALLEY, MALAYSIA

ISEE-438 Introduction: Pregnant women with high blood lead levels pose a high risk to the foetus, as lead can cross the placental barrier. Aim: The objective of this study was to identify the relationship between blood lead levels and the neuropsychological score of woman who were in their 3rd trimester of pregnancy. Methods: Respondents underwent routine antenatal check ups at a teaching hospital located in the Klang Valley area. Blood lead concentrations were analyzed using a graphite furnace Atomic Absorption Spectrophotometer. The neuropsychological scores were measured with the WHO Neurobehavioral Core Test Battery (NCTB). The test consists of 7 items: Digit Symbol, Trail Making, Digit Span, Benton Visual Retention Test, Pursuit Aiming, Santa Ana Manual Dexterity, Reaction Time and Movement Time tests. Results: The mean blood lead level was 7.78 ± 4.77 μg/dL. The mean score for the total NCTB test was 50.00 ± 5.24. Blood lead concentrations were found to be inversely correlated with the total NCTB score (r=−0.462, p<0.01). The correlation was about 21.3%. The General Linear Model (GLM) showed that age (b = −0.15, r = 0.017), weight (b=2.67, r=“0.05”) and height (b=−1.97, r=“0.05”) also influence the total neuropsychological scores. Conclusion: In conclusion, blood lead levels reduce the total neuropsychological scores. The scores for each of the 7 items were inversely and significantly correlated with blood lead concentrations, except for the Trail Making and Santa Ana Manual Dexterity tests.

Utility of the WHO Neurobehavioral Core Test Battery in Chinese Workers—A Meta-Aanalysis

We performed a meta-analysis to determine the most sensitive subtests of the WHO Neurobehavioral Core Test Battery (NCTB) when administered to Chinese workers. Extensive Chinese Biological Medical Database and MEDLINE searches, review of cited references, and discussion with other investigators were undertaken. Data were extracted from 39 eligible studies; the summary effects (effect sizes) were calculated using a fixed-effect model. Various exposure agents showed different sensitivities to the seven subtests of NCTB. For mercury-exposure, the Benton Visual Retention was the most sensitive subtest, with an effect size (95% CI) of 6.0 (4.4–7.6). For lead-exposure, the most sensitive subtests were the Pursuit Aiming II and Profile of Mood States, with effect sizes (95% CI) of 11.3 (8.3–14.3) and 10.6 (7.5–13.7), respectively. For organic solvents-exposure, Digit Span, Pursuit Aiming II, and Digit Symbol were the most sensitive subtests, with effect sizes (95− CI) of 4.7 (3.3–6.1), 4.6 (3.1–6.1), and 4.1 (2.7–5.5), respectively.

Neurological disorders in workers with low levels of lead in the blood. II--Neuropsychological disorders

This is a cross-sectional study with a randomized choice of individuals aiming at studying the validity of the Brazilian biological exposure limits applied to lead level in the blood (PbB) and delta-aminolevulinic acid in the urine (ALAU), which are 60 mu/dl and 10 mg/g.creat., respectively. Thus, twenty workers, whose PbB and ALAU values have been below these limits over the past two years, were selected at random at a battery plant in the State of S. Paulo, Brazil. The workers were submitted to a variation of the WHO Neurobehavioral Core Test Battery. The results were compared with those obtained for workers of a control group also chosen at random. The lead workers showed memory, mood and motor coordination disorders. Comparing these results with those obtained from the control group, a significant difference was observed (p-value < 0.02). The results indicate that the Brazilian biological exposure limits above should be reconsidered.

Performances of the WHO Neurobehavioral Core Test Battery among Mal Workers Occupationally Non-exposed to Neurotoxic Agents

Performances of the WHO Neurobehavioral Core Test Battery among Mal Workers Occupationally Non-exposed to Neurotoxic Agents

Application of neurobehavioral tests in a manufacturing automotive parts factory

Three neurobehavioral tests and a profile of mood states (POMS) test, which are included in the WHO neurobehavioral core test battery, were applied to 106 workers engaged in manufacturing automotive parts, especially for the purpose of determining the presence or absence of a significant difference in the score between a group of sixty-one workers chronically exposed to organic solvents and a group of forty-five workers unexposed. The scores of both pursuit-aiming and digit-symbol substitution tests were lower (P < 0.02 and P < 0.01, respectively, in analysis of covariance) in the group of exposed workers than in the group of unexposed workers. Furthermore, in the group of exposed workers, the pursuit-aiming and digit-symbol substitution scores showed a positive correlation (P < 0.05 and P < 0.01, respectively) to the fatigue score in the POMS test. On the other hand, the score of the digit span test showed no significant difference between the two groups. No significant correlation was found between the urinary hippuric acid level and the score of each of the three neurobehavioral tests. Therefore, among the exposed workers, the perceptual motor function evaluated in pursuit-aiming and digit-symbol tests seems to be affected. The neurobehavioral tests administered in this study are limited in number and in function, however, the comparison of their scores between the exposed and unexposed workers may suggest the presence of adversive effects of chronic exposure to organic solvents.

Adaptation of the WHO NCTB for Use in Poland for Detection of Effects of Exposure to Neurotoxic Agents

The purpose of the project was an assessment of psychometric characteristics of the WHO Neurobehavioral Core Test Battery (NCTB) (in traditional version) and the Hanninen Subjective Symptom Questionnaire adapted for Poland. The subjects were 119 greenhouse workers, 65 of them were exposed to organophosphorous pesticides and 54 were nonexposed ones. To assess the reliability, all tests from NCTB were administered twice with a 4-month interval. The results obtained in the first examination were used to determine the effects of gender, age, and education on tests performance. To determine the underlying factor structure of the test battery, the factor analysis was performed on 45 variables. The test–retest reliability coefficients ranged from 0.33 to 0.91. The lowest correlations were found for the Aiming Test—sum of errors ( r = 0.33) and the Benton Test ( r = 0.34). Gender appeared to be the most modifying factor of test performance. The factor analysis yielded 11 factors with eigenvalues greater than 1.0 (78.4% of variance explained).

A Study on the Neurobehavioral Effects of Occupational Exposure to Organic Solvents in Korean Workers

In order to investigate the neurobehavioral effects in workers occupationally exposed to organic solvents in Korea using WHO neurobehavioral core test battery (NCTB), a cross-sectional study of 113 male car painters and printers and 81 controls was conducted. Among the seven tests of the NCTB, only four tests-simple reaction time, Santa Ana dexterity, digit symbol, and Benton visual retention tests-were administered to the subjects because of time limitations. Painters and printers were exposed mainly to toluene, xylenes, and methyl ethyl ketone and often to solvent mixtures. The range of the solvent exposure level was 0.10-2.29 of hygienic effect. Poorer performance of Benton visual retention in the exposed group when compared to the control group was found after controlling confounders. No exposure-dependent effect was found. Further investigation with a matched control group regarding confounding factors is required for conclusive results.

神経行動評価システム（ＮＥＳ）とＷＨＯ神経行動コアテストバッテリー（ＮＣＴＢ）の日本語版の開発と信頼性の検討

神経行動評価システム（ＮＥＳ）とＷＨＯ神経行動コアテストバッテリー（ＮＣＴＢ）の日本語版の開発と信頼性の検討