• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.21 no.2
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• pp.116-122
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• 2011

Human occupational exposure to n-hexane has been associated with neurobehavioral symptoms such as depression, irritablity, acute irritation symptom, concentration disturbance and fatigue. Effects of monoamine oxidase (MAO) B and serotonin transporter receptor (5-HTTR) polymorphisms on the neurobehavioral symptoms were investigated in 70 male workers from TV and computer monitor manufacturing plants exposed to n-hexane. Neurobehavioral symptoms were assessed through a self-reported questionnaire and ambient level of n-hexane was measured by NIOSH method. Blood and urine were collected from each workers to determine the MAO(B), 5-HTTR and urinary 2,5-hexanedione(2,5-HD). The mean concentration of volatile n-hexane was $18.8{\pm}28.8ppm$ and that of urinary 2,5-HD was $1.07{\pm}1.47mg/g$ creatinine. Statistically significant associations with sexual disturbance were age and smoking. The frequencies of MAO(B) AA, AG and GG were 18.6%, 45.7% and 35.7%, respectively, and the frequencies of 5-HTTR ll, ls and ss genotype were 82.9%, 15.7% and 1.4%, respectively. MAO (B) gene polymorphisms had susceptibility to the neurobehavioral symptoms such as fatigue, concentration disturbance, irritability and acute irritation symptom and 5-HTTR gene polymorphism had susceptibility to the sleep disturbance and acute irritation symptom. On multiple logistic regression analysis for the neurobehavioral symptoms, memory disturbance was significantly associated with smoking(OR=6.752, 95% CI=37.46) and drinking(OR=4.033, 95% CI=1.252-12.98), emotional lability was MAO(B) genotype(OR=0.412, 95% CI=0.170-0.996), fatigue (OR=1.011, 95% CI=1.000-1.021) and acute irritation(OR=0.990, 95% CI=0.981-1.000) were working duration and sexual disturbance were significantly associated with age(OR=1.208, 95% CI=1.042-1.399), ambient n-hexane(OR=1.077, 95% CI=1.005-1.154) and 2,5-HD(OR=0.186, 95% CI=0.041-0.841). This finding implies that the MAO (B) and 5-HTTR polymorphisms may affect susceptibility for specific neurobehavioral symptoms associated with n-hexane exposure in workers.

• Korean Journal of Psychosomatic Medicine
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• v.4 no.2
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• pp.170-181
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• 1996

Objective : This study was tried to investigate the specific relationships among cognitve function, neurbehavioral symptoms, and daily living functions, as well as provide the guidline of more proper clinical approches for patients with subcortical cerebrovascular disease. Objects and Methods Subjects were 85 patients whose diagnosis was confirmed by brain CT or MRI and controls were 195 normal persons matched by educational level with the subjects. The cognitive functions were evaluated by BNA(Benton neuropsychiatric assessment), subjective neurobehavioral symptoms by SCL-90-R(Sympton Check List-90-Revised), objective neurobehavioral symptoms by NRS(Neurobehavioral Rating Scale), and daily living function symptoms by NRS(Neurobehavioral Rating Scale), and daily living function by GERRI(Geriatric Evaluation by Relative's Rating Instrument) and IADL(Instrumental Activities of Daily Living Scale). Results: 1) Subjects showed significantly lower cognitive functions than controls in all tests of BNA except Lt-Rt Orientation Test(p=0.09) and facial Recognition Test(p=0.186). 2) In subjective neurobehavioral symptoms, subjects showed significantly lower scores in all symptoms except anxiety(p=0.059), hostility(p=0.159), and phobic anxiety(p=0.849). But in objects neurobehavioral symptoms, subjects showed significantly higher in scores in psychoticism (p=0.000) and neuroticism(p=0.025) of NRS. 3) The score of social functioning of GERRI(p=0.000) and that of IADL(p=0.000) were significantly higher in subjects than in controls. 4) for correlation between cognitive and daily living functions, there were significant correlations between the scores of all items on BNA and the score of cognitive or social function of GERRI and the socre of MDL in corntrols, whereas in subjects, there were significant correlations only between the scores of BNA and the score of IADL. 5) for correlation between neuroehavioral symptoms and daily living functions, there were significant correlatons between the socre of subjective neurobehavioral symptoms and the scores of all subscales of GERRI and the score of MDL in controls. On the contrary, in subjects, there were significant correlations between the score of social function of GERRI and the score of objective neurobehavioral symptoms such as psychoticism, agitiation-hostility, and decrease d motivation-emotional withdrawl. Conclusion : Above results suggest that disturbances in specific function of brain may play a role as a predictor of impairments with specific daily living functions and also suggest that specific correlations among various functions may be useful as clinical parameters for setting of the treatment goal and for assessing the ongoing process in the treatment and rehavilitation of the patients with subcortical cerebrovascular disease.

• Safety and Health at Work
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• v.4 no.3
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• pp.123-135
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• 2013

Exposure to manganese (Mn) is associated with neurobehavioral effects. There is disagreement on whether commonly occurring exposures in welding, ferroalloy, and other industrial processes produce neurologically significant neurobehavioral changes representing parkinsonism. A reviewof methodological issues in the human epidemiological literature onMnidentified: (1) studies focused on idiopathic Parkinson disease without considering manganism, a parkinsonian syndrome; (2) studies with healthy worker effect bias; (3) studies with problematic statistical modeling; and (4) studies arising from case series derived from litigation. Investigations with adequate study design and exposure assessment revealed consistent neurobehavioral effects and attributable subclinical and clinical signs and symptoms of impairment. Twenty-eight studies show an exposure-response relationship between Mn and neurobehavioral effects, including 11 with continuous exposure metrics and six with three or four levels of contrasted exposure. The effects of sustained low-concentration exposures to Mn are consistent with the manifestations of early manganism, i.e., consistent with parkinsonism. This is compelling evidence thatMnis a neurotoxic chemical and there is good evidence that Mn exposures far below the current US standard of $5.0mg/m^3$ are causing impairment.

• Sleep Medicine and Psychophysiology
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• v.3 no.1
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• pp.56-67
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• 1996

Objectives : This study was designed to find clinical factors that could be differentiated by the lateralization of lesion and also find clinical factors to predict the lateralization of lesion. Methods : The subjects were 65 cooperative inpatients and outpatients with non-traumatic subcortical cerebrovascular disease without neurologic and psychiatric history from January 1995 to September 1995 ; 48 patients in Kyung Hee University, Oriental Medicine Hospital, 35 patients in Anam Hospital, Korea University were examined as subjects, but authors excluded 20 patients whose data were incomplete or who had uncertain lesions on brain CT or MRI. The 65 patients were divided into three groups-group with left hemispheric lesion, group with right hemispheric lesion, group with both hemispheric lesion-according to the finding of brain imaging study. Their cognitive functions were evaluated by the Benton Neuropsychological Assessment(BNA), their subjective neurobehavioral symptoms by Symptom Check List-90-R(SCL-90-R), their objective neurobehavioral symptoms by Neurobehavioral Rating Scale, and their daily living functions by Geriatric Evaluation by Relative's Rating Instrument(GERRl) and Instrumental Activities of Daily Living Scale(IADLs). Results : The results were as follows : 1) The results of cognitive function test indicated that the group with right hemispheric lesion showed low functions in Tactile Form Perception(left), the group with left hemispheric lesion showed low functions in Finger localization(right), the group with right hemispheric lesion showed low functions in Finger Localization(left). 2) Though, there were little significant differences in subjective neurobehavioral symptoms, the group with right hemispheric lesion showed higher scores in all symptoms except hostility. 3) Though, there were little significant differences in objective neurobehavioral symptoms, the group with both hemispheric lesion showed higher scores in cognition, guilty/disinhibition, the group with left hemispheric lesion showed higher scores in lability of mood, the group with right hemispheric lesion showed highest scores in psychotism, neurotism, agitation-hostility and decreased motivation/emotional withdrawal. 4) There were little significant differences among three groups in Daily Living Functions, but the group with right hemispheric lesion showed the lowest functions in Instrumental Activities of Daily Living. 5) As a result of discriminant analysis on each factor's contribution to the prediction of lesion, Finger Localization(left), Phoneme Discrimination and Tactile Form Perception(right) showed that they had the potentiality to predict lesion. Conclusion : The results suggest that there are little significant differences among the groups of three non-traumatic subcortical cerebrovascular disease in cognitive functions, but the group with right hemispheric lesion showed more serious and various changes in subjective and objective neurobehavioral symptoms, and showed low functions in Instrumental Activities of Daily Living. This results suggest the possibility that the decline of the daily living function in the group with right hemispheric lesion were due to various symptoms, not due to cognitive dysfunction. The confirmation of the possibility should be worked out through the follow-up study of some groups containing cortical lesion. Apart from these findings, Finger Localization, Tactile Form Perception(right) and Phoneme Discrimination suggest that they can be used as clinically valuable cognitive parameters that predict the lateralization of lesion in non-traumatic cerebrovascular disease.

• Safety and Health at Work
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• v.15 no.1
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• pp.9-16
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• 2024

Background: E-waste workers in Hong Kong are handling an unprecedented amount of e-waste, which contains various neurotoxic chemicals. However, no study has been conducted to evaluate the neurological health status of e-waste workers in Hong Kong. This study aimed to evaluate the prevalence of neurobehavioral alterations and to identify the vulnerable groups among Hong Kong e-waste workers. Methods: We recruited 109 Hong Kong e-waste workers from June 2021 to September 2022. Participants completed standard questionnaires and wore a GENEActiv accelerometer for seven days. Pittsburgh Sleep Quality Index and Questionnaire 16/18 (Q16/18) were used to assess subjective neurobehavioral alterations. The GENEActiv data generated objective sleep and circadian rhythm variables. Workers were grouped based on job designation and entity type according to the presumed hazardous level. Unconditional logistic regression models measured the associations of occupational characteristics with neurobehavioral alterations after adjusting for confounders. Results: While dismantlers/repairers and the workers in entities not funded by the government were more likely to suffer from neurotoxic symptoms in Q18 (adjusted odds ratio: 3.18 [1.18-9.39] and 2.77 [1.10-7.46], respectively), the workers from self-sustained recycling facilities also have poor performances in circadian rhythm. Results also showed that the dismantlers/repairers working in entities not funded by the government had the highest risk of neurotoxic symptoms compared to the lowest-risk group (i.e., workers in government-funded companies with other job designations). Conclusion: This timely and valuable study emphasizes the importance of improving the working conditions for high-risk e-waste workers, especially the dismantlers or repairers working in facilities not funded by the government.

• Journal of Preventive Medicine and Public Health
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• v.27 no.3 s.47
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• pp.557-567
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• 1994

This study was conducted to examine the effect of chronic low dose organic solvent exposures in the industries towards then neurobehavioral functions of workers. Subjective symptoms on neurobehavioral function as well as a visual reaction time test (Flicker test) were administered to 94 exposed and 162 unexposed workers in a oil refinery and some other auto-repair shops. The results obtained were as follows : 1. Symptom complaints were higher and Flicker test values were lower in exposed workers than in unexposed workers. 2. Flicker valus were Inversely correlated with urinary Hippuric acid concentration in exposed workers(r=-0.26, p<0.05). 3. Flicker valus were inversely co..elated with Subjective symptom score(r=-0.15, p<0.05). Low Flicker value were also related with some subjetive symptoms such as 'Dimmed vision', 'Nightmare', 'Weakness on extrimity' in workers as a whole. While symptoms of 'Dimmed vision ', 'Nightmare' only observed among exposed workers.

• Clinical and Experimental Pediatrics
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• v.51 no.9
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• pp.935-943
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• 2008

Attention deficit hyperactivity disorder (ADHD) is a neurobehavioral developmental disorder characterized by a persistent pattern of inattention and/or hyperactivity, as well as forgetfulness, poor impulse control or impulsivity, and distractibility. The recommended evaluation includes documenting the type and severity of ADHD symptoms, verifying the presence of normal vision and hearing, screening for comorbid psychological conditions, reviewing the child's developmental history and school performance, and applying objective measures of cognitive function. Prevailing opinion characterizes ADHD as a disorder of executive function attributable to abnormal dopamine transmission in the frontal lobes and frontostriatal circuitry. A clearly defined etiology remains unknown, but studies suggest a strong genetic link. The aim of treatment is to decrease symptoms, enhance functionality, and improve well-being for the child and his or her close contacts. Stimulants remain the pharmacological agents of first choice for the management of ADHD, and psychosocial, behavioral and educational strategies that enhance specific behaviors may improve educational and social functioning in children with ADHD.

• Biomolecules & Therapeutics
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• v.27 no.4
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• pp.349-356
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• 2019

Behavioral analysis in mice provided important contributions in helping understand and treat numerous neurobehavioral and neuropsychiatric disorders. The behavioral performance of animals and humans is widely different among individuals but the neurobehavioral mechanism of the innate difference is seldom investigated. Many neurologic conditions share comorbid symptoms that may have common pathophysiology and therapeutic strategy. The forced swim test (FST) has been commonly used to evaluate the "antidepressant" properties of drugs yet the individual difference analysis of this test was left scantly investigated along with the possible connection among other behavioral domains. This study conducted an FST-screening in outbred CD-1 male mice and segregated them into three groups: high performers (HP) or the active swimmers, middle performers (MP), and low performers (LP) or floaters. After which, a series of behavioral experiments were performed to measure their behavioral responses in the open field, elevated plus maze, Y maze, three-chamber social assay, novel object recognition, delay discounting task, and cliff avoidance reaction. The behavioral tests battery revealed that the three groups displayed seemingly correlated differences in locomotor activity and novel object recognition but not in other behaviors. This study suggests that the HP group in FST has higher locomotor activity and novelty-seeking tendencies compared to the other groups. These results may have important implications in creating behavior database in animal models that could be used for predicting interconnections of various behavioral domains, which eventually helps to understand the neurobiological mechanism controlling the behaviors in individual subjects.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• v.22 no.2
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• pp.74-80
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• 2011

Attention-deficit hyperactivity disorder (ADHD) is a neurobehavioral disorder with an onset of symptoms before 7 years of age, often starting as early as the preschool years. The off-label use of methylphenidate (MPH) for 3- to 6-year-old preschool children with ADHD is being more common, although MPH is not licensed for use in children younger than age 6 years, in most countries. Despite the limited data, the review of the literature suggests that MPH meets evidence based criteria as beneficial and safe for carefully diagnosed ADHD preschool children. Carefully monitored administration of evidence-based psychotropic medication in preschool children with ADHD may be indicated if psychosocial treatments are ineffective.

• Korean Journal of Psychosomatic Medicine
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• v.12 no.2
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• pp.103-121
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• 2004

Conversion disorder and factitious disorder should be ruled out before making diagnosis of malingering. For this work, inspection of patient's behavior along with complete neurological examinations, psychological tests, and meticulous psychiatric interview are necessary. Facial expression test, thermography, dynamometry were failed differentiating conversion disorders to the malingered pain and motor symptoms, however, controlled diagnostic block showed positive result partly in patients with regional or cervical pain syndrome. Chronic pain patients who are related to the process of litigation encounter stressful life situations which lead them into various neurobehavioral and psychosocial complications. Most of suspected malingered patients would not revealed pure form rather mixed with factitious and/or conversion features. At the time of increasing number of chronic patients associated with traffic accidents or industrial injuries who are involved in litigation, psychiatrist are needed sharp eyes and tenacity for evaluating malingering or medically unexplained symptoms.