Childhood is a critical period in the development of their central nervous system. Stressful life events in childhood may have both short-term and long-term impacts on their mental health. To cope with the COVID-19 epidemic, a series of policies have been adopted worldwide, such as the school closure and the social distancing, which have changed the children's psychosocial environment and are associated with an increased risk of mental health problems. This paper reviews the mental health problems that the children might face amid the COVID-19 epidemic, and discusses the countermeasures that the government, the society, and the family might take. Finally, suggestions are made to promote the psychological recovery of children after the epidemic.

The COVID-19 pandemic has severely affected people's daily life globally, especially for the physical and mental health of children and adolescents, the vulnerable group. This paper reviews the studies, up to August 24, 2020, focusing on the following four aspects. Firstly, the mental stressors among children and adolescents are discussed from national and society, school and community, family and individual perspectives, such as the social isolation, the health care facility closures, the school closures, the economic deterioration, the home quarantine, the domestic violence and abuse, the increased screen time, and others. Secondly, the main types of psychological problems in teenagers during the COVID-19 are discussed. Emotional problems mainly include the anxiety, the depression, the loneliness, the sleep problems, the psychosomatic problems and the stress-related problems. Behavioral problems mainly include:the internet addiction, the sexual abuse behaviors, the parent-child conflicts, and others. Finally, children and adolescents are divided into five categories according to different risks under the background of COVID-19:the ordinary children, the children living in high exposure risk areas, the children with their caregivers being affected or being frontline workers, the quarantined children, the children with other diseases and the infected children. And intervention recommendations include the health education, the epidemic prevention, the knowledge popularization, the parent accompaniment; the hospital 24-hour on-duty nursing system, the online consultation and the online pharmacy; the remote interactive online education, the remote psychiatry, the book therapy, the music therapy, the emotion-focused therapy (EFT), the parent-child interaction therapy (PCIT), the cognitive behavioral writing therapy(CBWT), the eye movement desensitization and reprocessing (EMDR) and the drug therapy.

This paper examines the overall effect of the online video group coaching for university students during the pandemic of COVID-19. 39 students in a university located in Beijing in 4 online groups (6 sessions of the online group coaching) are selected for 6 weeks from March to May 2020. The evaluation instruments include an psychological status questionnaire and a questionnaire of individual group effect assessment. The comparison of the scores based on the psychological status questionnaire before and after the 6-week group coaching shows a significant increase in the satisfaction of the group members with respect to the learning status and the special ability after the coaching, highly associated with the degree of the help provided by the online video group coaching and the appropriateness of evaluating the work of the group's mentors, the degree of the progress that the group members wished to make, and the degree of the support that the group members feel. The results are statistically significant. The online video group coaching during the pandemic of COVID-19 is effective, associated to the group development, the work of group instructors and the level of group members.

Children's mental disorder is a type of abnormal behavior and mental disorder in the childhood and the adolescence, with a high incidence rate, as one of the important problems all over the world. This paper reviews the genetics research progress of several common childhood mental disorders (attention deficit, hyperactivity disorder, autism, and others). Most childhood mental disorders have a high degree of heritability. Understanding the pathogenesis of childhood mental disorders from a genetic point of view, identifying the disease-related genetic loci, and further understanding the function of the genetic loci, will provide important basic data for the disease prevention, the diagnosis and the precision treatment. This paper discusses the main genetic research types and the related main results of several common childhood mental disorders, and on this basis, outlines the functional research methods and results after the identification of the genetic loci, and finally proposes some future directions for the genetic research of childhood mental disorders. The result will prouide inspiration for the future genetic research of childhood mental disorders.

Improving the mental well-being of children and adolescents is a significant component of the Healthy China 2030 Initiative, among which the mental health status of left-behind children in rural China deserves more attention. This paper systematically reviews the existing empirical studies of the general status and the influencing factors of the mental health among rural left-behind children, and the intervention studies for improving the mental well-being of this population. Evidences show that, despite of the previous theoretical and empirical work focusing on the mental health of left-behind children, further studies are still needed to set up a consistent concept of left-behind children, with the standard measuring tools of mental health, to carry out the longitudinal studies, to develop the cultural-specific intervention in Chinese rural communities and to facilitate the multidisciplinary collaborations.

The iron deficiency is the most common micro-nutrient deficiency in children, with a large number of children falling victims in China, especially infants, which are at a very high risk. The sleep plays an important part in the body's development, repair and adjustment, and is particularly important in the developing stage. It is revealed by increasing number of studies that the iron deficiency is probably associated with several common sleep disorders in children. This paper reviews the cutting-edge studies of iron deficiency-related sleep disorders in children, including the clinical characteristics, the possible pathological mechanism and the iron supplement therapy. The iron deficiency may lead to increased abnormal activities during sleep in children by causing disorders of neurotransmitters, altering the processes of the myelination and the formation of dendrites. The iron supplementation therapy was reported to improve the symptoms of sleep movements in some children.

The mental health is important in the development of adolescent's overall quality. In this paper, the genogram technology is used to evaluate the mental health status of adolescent cases, with the symptom self-rating scale and the family environment scale being taken to explore the effect of the genograms in the identification of adolescent mental health risks. It is shown that the family environment is an important factor affecting the adolescent mental health, the child attachment style can be used to predict the adolescent mental health status, and the cultural factors have a profound influence on the adolescent mental health. It is also shown that the genogram is an effective and practical means in the evaluation of the adolescent mental health. The method of the psychological assessment based on the genogram technology can be used both for the clinical assessment and for the questionnaire statistical assessment. This study clears the connotation of the psychological assessment methods, helps the application of the genograms in the qualitative research, and the results can be used in the future related researches.