The brain maintains homeostasis and normal microenvironment through dynamic interactions of neurons and neuroglial cells to perform the proper information processing and normal cognitive functions. Recent post-mortem investigations and animal model studies demonstrated that the various brain areas such as cerebral cortex, hippocampus and amygdala have abnormalities in neuroglial numbers and functions in subjects with mental illnesses including schizophrenia, dementia and mood disorders like major depression and bipolar disorder. These findings highlight the putative role and involvement of neuroglial cells in mental disorders. Herein I discuss the physiological roles of neuroglial cells such as astrocytes, oligodendrocytes, and microglia in maintaining normal brain functions and their abnormalities in relation to mental disorders. Finally, all these findings could serve as a useful starting point for potential therapeutic concept and drug development to cure unnatural behaviors and abnormal cognitive functions observed in mental disorders.

Mood disorder is a common psychiatric illness with a high lifetime prevalence in the general population. A serious problem such as suicide is commonly occurring in the patients with depression. Till now, the monoamine hypothesis has been the most popular theory of pathogenesis for depression. However, the more specific pathophysiology of depression and cellular molecular mechanism underlying action of commercial antidepressants have not been clearly defined. Several recent studies demonstrated that glial cells, especially astrocytes, are a promising answer to the pathophysiology of depression. In this article, current understanding of biology and molecular mechanisms of glial cells in the pathology of mood disorder and new research on the pathophysiology of depression will be discussed.

Neuroglial cells are fundamental for brain homeostasis and defense to intrinsic or extrinsic changes. Loss of their function and over-reactivity to stimuli contribute to the aging of brain. Alzheimer's disease (AD) could be caused by more dramatic response in neuroglia associated with various chemokines and cytokines. Neuroglia of the AD brain shares some phenotypes with aging neuroglia. In addition, neuroglial activation and neuroinflammation are commonly showed in neurodegeneration. Thus neuroglia would be a promising target for therapeutics of AD.

In the past decade, structural, molecular, and functional changes in glial cells have become a major focus in the search for the neurobiological foundations of schizophrenia. Glial cells, consisting of oligodendrocytes, astrocytes, microglia, and nerve/glial antigen 2-positive cells, constitute a major cell population in the central nervous system. There is accumulating evidence of reduced numbers of oligodendrocytes and altered expression of myelin/oligodendrocyte-related genes that might explain the white matter abnormalities and altered inter- and intra-hemispheric connectivities that are characteristic signs of schizophrenia. Astrocytes play a key role in the synaptic metabolism of neurotransmitters ; thus, astrocyte dysfunction may contribute to certain aspects of altered neurotransmission in schizophrenia. Increased densities of microglial cells and aberrant expression of microglia-related surface markers in schizophrenia suggest that immunological/inflammatory factors are of considerable relevance to the pathophysiology of psychosis. This review describes current evidence for the multifaceted role of glial cells in schizophrenia and discusses efforts to develop glia-directed therapies for the treatment of the disease.

Objectives Social workers can suffer from occupational stress resulting from dealing with clients, which might lead to metal health problems. We aimed to investigate the association of duty-related traumatic experiences and stress coping strategies with post-traumatic stress symptoms among social workers in public sector. Methods A total of 110 social workers in public sector (men 30.9%, $36.5{\pm}7.6$ yrs) participated in this study. All subjects were evaluated the frequency and the impact of duty-related traumatic events. Additionally, they completed questionnaires including the Impact of Event Scale-Revised for post-traumatic stress symptoms, the Beck Depression Inventory-II for depressive symptoms, the Scale for Suicidal Ideation for suicide symptoms and the Ways of Coping Checklist for stress coping strategies. Results The most frequent traumatic events were "Violent or abusive language from a client" (95.0%) and "Client made a fuss" (94.5%). The most distressing traumatic event was "Seeing a dead body on duty" (7.6 out of 10), which predicted post-traumatic stress symptoms (odds ratio 4.04 ; 95% confidence interval, 1.79-9.11). Among 4 types of stress coping strategies, the emotion-focused coping was positively correlated with post-traumatic stress symptoms after controlling age and sex (${\beta}$ = 0.50, p < 0.001). Conclusions Social workers in public sector showed high level of post-traumatic stress symptoms. Duty-related traumatic events and the emotional-focused coping strategies were associated with the severity of post-traumatic stress symptoms. The modification of stress coping strategies would alleviate post-traumatic stress symptoms in social workers in public sector.

Objectives The combination extract of four kinds of herbs, Gastrodia elata, Liriope platyphylla, Dimocarpus longan, and Salvia miltiorrhiza, has shown to have memory improving effects in mice. The aim of this study was to investigate the efficacy and safety of the herbal mixture for improving working memory as well as microstructural changes in white matter integrity in individuals with subjective memory complaints. Methods Seventy-five individuals with subjective memory complaints were assigned to receive either placebo (n = 15) or herbal mixture (low-dose group, n = 30 and high-dose group, n = 30) supplementation in an 8-week, randomized, double-blind, placebo-controlled clinical trial. Changes in working memory performance and fractional anisotropy (FA) values reflecting white matter integrity from baseline to 8-week endpoint were assessed. Results The herbal mixture group showed an increase in working memory performance compared to the placebo group (p for interaction = 0.001). In addition, the herbal mixture group showed an increase in FA values in the temporo-parietal regions (corrected p < 0.05), which are crucially involved in working memory function and are among the most affected regions in patients with cognitive impairments. Conclusions Findings from this study indicate that the herbal mixture may be a promising therapeutic option for individuals with subjective memory complaints.

Objectives Although ginseng has been reported to protect neuronal cells and improve various cognitive functions, relationship between ginseng supplementation and response inhibition, one of the important cognitive domains has not been explored. In addition, effects of ginseng on in vivo human brain have not been investigated using the diffusion tensor imaging (DTI). The purpose of the current study is to investigate changes in intrusion errors and white matter microstructure after Korean Red Ginseng supplementation using standardized neuropsychological tests and DTI. Methods Fifty-one healthy participants were randomly allocated to the Korean Red Ginseng (n = 26) or placebo (n = 25) groups for 8 weeks. The California Verbal Learning Test was used to assess the number of intrusion errors. Intelligence quotient (IQ) was measured with the Korean Wechsler Adult Intelligence Scale. Depressive and anxiety symptoms were evaluated using Hamilton Depression Rating Scale, Hamilton Anxiety Rating Scale, and Hopkins Symptom Checklist-25. The fractional anisotropy (FA) was measured from the brain DTI data. Results After the 8-week intervention, Korean Red Ginseng supplementation significantly reduced intrusion errors after adjusting age, sex, IQ, and baseline score of the intrusion errors (p for interaction = 0.005). Change in FA values in the left anterior corona radiata was greater in the Korean Red Ginseng group compared to the placebo group (t = 4.29, p = 0.04). Conclusions Korean Red Ginseng supplementation may be efficacious for improving response inhibition and white matter microstructure integrity in the prefrontal cortex.

Objectives The power spectral analysis of electroencephalogram has been widely used to reveal the pathophysiology of the alcoholic brain. However, the results were not consistent and the three dimensional study can be hardly found. The purpose of this study was to investigate characteristics of the three dimensional electroencephalographic (EEG) activity of alcohol dependent patients using standardized low resolution electromagnetic tomography (sLORETA). Methods The participants consisted of 30 alcohol dependent patients and 30 normal healthy controls. All the participants were males who had refrained from alcohol at least one month and were not taking any medications. Thirty two channel EEG data was collected in the resting state with eyes-closed condition during 30 seconds. The three dimensional data was compared between two groups using sLORETA for delta, theta, alpha, beta1, beta2, and beta3 frequency bands. Results sLORETA revealed significantly increased brain cortical activity in alpha, beta1, beta2, and beta3 bands each in alcohol dependent patients compared to normal controls. The voxels showing the maximum significance were in the left transverse temporal gyrus, left superior temporal gyrus, left anterior cingulate, and left fusiform gyrus in alpha, beta1, beta2, and beta3 bands respectively. Conclusions These results suggest that chronic alcohol intake may cause neurophysiological changes in cerebral activity. Therefore, the measuring of EEG can be helpful in understanding the pathophysiology of cognitive impairements in alcohol dependence.