Differential Genetic and Environmental Influences on Reactive and Proactive Aggression in Children

While significant heritability for childhood aggression has been claimed, it is not known whether there are differential genetic and environmental contributions to proactive and reactive forms of aggression in children. This study quantifies genetic and environmental contributions to these two forms of aggression in an ethnically diverse urban sample of 9–10 year old twins (N = 1219), and compares results across different informants (child self-report, mother, and teacher ratings) using the Reactive–Proactive Aggression Questionnaire (RPQ). Confirmatory factor analysis of RPQ items indicated a significant and strong fit for a two-factor proactive–reactive model which was significantly superior to a one-factor model and which replicated across gender as well as the three informant sources. Males scored significantly higher than females on both self-report reactive and proactive aggression, findings that replicated on mother and teacher versions of the RPQ. Asian–Americans scored lower than most ethnic groups on reactive aggression yet were equivalent to Caucasians on proactive aggression. African–Americans scored higher than other ethnic groups on all measures of aggression except caregiver reports. Heritable influences were found for both forms of aggression across informants, but while boys’ self-reports revealed genetic influences on proactive (50%) and reactive (38%) aggression, shared and non-shared environmental influences almost entirely accounted for girls’ self-report reactive and proactive aggression. Although genetic correlations between reactive and proactive aggression were significant across informants, there was evidence that the genetic correlation was less than unity in boys self reported aggression, indicating that genetic factors differ for proactive and reactive aggression. These findings provide the first evidence for varying genetic and environmental etiologies for reactive and proactive aggression across gender, and provide additional support for distinction between these two forms of aggression.     

Psychiatric Disorders in Clinical Genetics I: Addressing Family Histories of Psychiatric Illness

This is the first article of a two-part professional development series addressing genetic counseling for personal and family histories of psychiatric disorders. It is based on an Educational Breakout Session presented by the Psychiatric Special Interest Group of the National Society of Genetic Counselors at the 2006 Annual Education Conference. This article examines issues that arise in addressing family histories of psychiatric illness, while the second article in the series considers the generation and provision of individualized recurrence risks for psychiatric disorders. In this article we discuss the importance of managing uncertainty for affected individuals and their close family members who have been referred to genetics for a number of different indications. We then use four simulated cases to make recommendations about the scope and timing of discussions related to the psychiatric family history.     

Gene Concepts and Genethics: Beyond Exceptionalism

The discursive explosion that was provoked by the new genetics could support the impression that the ethical and social problems posed by the new genetics are somehow exceptional in their very nature. According to this view we are faced with special ethical and social problems that create a challenge so fundamental that the special label of genethics is needless to justify. The historical account regarding the evolution of the gene concepts could serve us to highlight the limits of what we know about genes and what we can do with genes. The widespread notion about the exceptionality of genetic knowledge and its applicative possibilities is hardly justifiable and leads to misunderstandings regarding the conceptualization of the ethical and social problems we might face. Following a more realistic interpretation of the role of genes in human life we might avoid a whole set of fictive dilemmas and counterproductive regulatory efforts in bioethics. Bioethical discourse should move from the gene-centered scientific discourse toward the more sophisticated and complex discourses where human development represented as a matter of complex interactions between genomes and environments, between genes, educational factors, nutritional regimes, and other different developmental resources. If a gene is seen as one among the different developmental resources that are shaping a given human trait then both genethics and genetic exceptionalism could hardly be represented as a justified approach in discussing the ethical and social problems of genetics.     

Code of Ethics of the National Society of Genetic Counselors: Explication of Revisions

The Code of Ethics (COE) of the National Society of Genetic Counselors (NSGC) was adopted in 1992. In 2004, the NSGC leadership appointed the Code of Ethics Work Group (COEWG) to consider revisions to the NSGC COE based on advice from the NSGC legal counsel, and to consider additional changes given growth in the scope of genetic counseling practice since the adoption of the original COE. After input from the NSGC membership, changes to the COE addressing the recommendations of the NSGC legal counsel were approved in December 2004. The COEWG then reviewed ethical codes and codes of professional conduct from 22 professional organizations, deemed to have similar goals and philosophies to the NSGC, searching for themes that encompassed genetic counseling practice that might not yet be addressed in the NSGC COE. Additional revisions to the COE were proposed, and after feedback from the NSGC membership, the revised COE was approved in January 2006 by majority vote of full members of the NSGC. The explications for the 2004 and 2006 revisions are presented.     

The Influence of Cancer-related Distress and Sense of Coherence on Anxiety and Depression in Patients with Hereditary Cancer

This study examines the association between Sense of Coherence and anxiety and depression amongst patients at risk of hereditary cancer receiving genetic counseling. When writing this article, 144 patients referred for genetic counseling due to a suspicion of hereditary cancer in the family were recruited for this multicentered longitudinal study on the psychosocial aspects of genetic counseling in Norway. A total of 96 (66%) patients responded to the follow-up survey distributed 6 months after genetic counseling. This survey included the Sense of Coherence-29 Scale, Impact of Event Scale, and Hospital Anxiety and Depression Scale. Multiple regression analyses were applied. Our results show association between cancer-related distress and symptoms of anxiety and depression. Sense of Coherence is significantly associated with both anxiety and depression. The hypothesis of Sense of Coherence buffering cancer-related distress and the possible impact of these findings for genetic counseling are discussed.     

Biotechnology,ethics and education

Fundamental differences between current and past knowledge in the field of biotechnology mean that we now have at our disposal the means to irreversibly change what is meant by ‘human nature’. This paper explores some of the ethical issues that accompany the (as yet tentative) attempt to increase scientific control over the human genetic code in what amounts to a diminishing of difference and the reduction of human life to scientific explanations at the expense of spiritual, cultural and communal considerations. Within such a limited view, the critical role of education is reduced in favour of promoting psychological efficiency, with the possibility of accelerating learning and increasing intellectual capacity through genetic manipulation. A major concern expressed in the paper is the fine line between corrective therapy and psychological enhancement: Who should be defining the normal range of human difference? And what degree of caution should be required in redesigning future generations? The unknown dangers inherent in the (perhaps irreversible) application of genetic technology to human life suggests that current precautions may not go far enough in recognising that education is a contestable field.     

试论心身疾病的中医病机

心身疾病是指那些心理一社会因素在疾病的发生和发展中起重要作用的躯体疾病。其概念决定了心身疾病不具有专业领域性,不同心身疾病有着不同的病理变化。发掘其病理共性、找寻规律性,对该学科发展的标准化方向至关重要。该文从中医基本病机层次,探讨了心身疾病的发生、发展与变化的机理,试图对科研与临床操作提供有益思路。     

Short-Term Memory Deficits Are Not Uniform in Down and Williams Syndromes

Neuropsychological investigation of the development of the mnesic function in mental retardation has primarily focused on evaluating short-term memory (STM). Studies have often documented a reduced verbal short-term memory span in individuals with mental retardation and with Down syndrome in particular, compared to groups of mental age-matched controls. However, recent evidence suggests that verbal short-term memory is not equally impaired in all individuals with mental retardation. Findings in children with Williams syndrome are particularly relevant in this regard. Also, data concerning STM for visual information suggest that visual-object and visual-spatial working memory may be differently compromised in people with mental retardation. In particular, individuals with Williams syndrome exhibit specific difficulties in visual-spatial but not in visual-object working memory tasks compared to typically-developing children matched for mental age. Instead, people with Down syndrome show reduced performance in both visual-spatial and visual-object tests. Taken together, these results reinforce the view that intellectual disability is not a unitary condition characterized by homogeneous slowness of cognitive development but a variety of conditions in which some cognitive functions may be more disrupted than others. The finding that the working memory deficit in individuals with Williams and Down syndrome may be qualitatively differentiated also supports the hypothesis that it is not simply a manifestation of general cognitive impairment but, rather, the expression of a specific deficit of a discrete cognitive ability.     

Animal foraging and the evolution of goal-directed cognition

Foraging- and feeding-related behaviors across eumetazoans share similar molecular mechanisms, suggesting the early evolution of an optimal foraging behavior called area-restricted search (ARS), involving mechanisms of dopamine and glutamate in the modulation of behavioral focus. Similar mechanisms in the vertebrate basal ganglia control motor behavior and cognition and reveal an evolutionary progression toward increasing internal connections between prefrontal cortex and striatum in moving from amphibian to primate. The basal ganglia in higher vertebrates show the ability to transfer dopaminergic activity from unconditioned stimuli to conditioned stimuli. The evolutionary role of dopamine in the modulation of goal-directed behavior and cognition is further supported by pathologies of human goal-directed cognition, which have motor and cognitive dysfunction and organize themselves, with respect to dopaminergic activity, along the gradient described by ARS, from perseverative to unfocused. The evidence strongly supports the evolution of goal-directed cognition out of mechanisms initially in control of spatial foraging but, through increasing cortical connections, eventually used to forage for information.