Differential acquisition of lever pressing in inbred and outbred mice: comparison of one-lever and two-lever procedures and correlation with differences in locomotor activity

Recent progress in mouse genetics has led to an increased interest in developing procedures for assessing mouse behavior, but relatively few of the behavioral procedures developed involve positively reinforced operant behavior. When operant methods are used, nose poking, not lever pressing, is the target response. In the current study differential acquisition of milk-reinforced lever pressing was observed in five inbred strains (C57BL/6J, DBA/2J, 129X1/SvJ, C3H/HeJ, and BALB/cJ) and one outbred stock (CD-1) of mice. Regardless of whether one or two levers (an "operative" and "inoperative" lever) were in the operant chamber, a concomitant variable-time fixed-ratio schedule of milk reinforcement established lever pressing in the majority of mice within two 120-min sessions. Substantial differences in lever pressing were observed across mice and between procedures. Adding an inoperative lever retarded acquisition in C57BL/6J, DBA/2J, 129X1/SvJ, and C3H/HeJ mice, but not in CD-1 and BALB/cJ mice. Locomotor activity was positively correlated with number of lever presses in both procedures. Analyses of durations of the subcomponents (e.g., time to move from hopper to lever) of operant behavior revealed further differences among the six types of mice. Together, the data suggest that appetitively reinforced lever pressing can be acquired rapidly in mice and that a combination of procedural, behavioral, and genetic variables contributes to this acquisition.     

The Nature and Significance of Behavioural Genetic Information

In light of the human genome project, establishing the genetic aetiology of complex human diseases has become a research priority within Western medicine. However, in addition to the identification of disease genes, numerous research projects are also being undertaken to identify genes contributing to the development of human behavioural characteristics, such as cognitive ability and criminal tendency. The permissibility of this research is obviously controversial: will society benefit from this research, or will it adversely affect our conceptions of ourselves and each other? When assessing the permissibility of this research, it is important to consider the nature and deterministic significance of behavioural genetic information. Whilst todate there has been much discussion and debate about the properties of genetic information per se and genetic determinism, this has not been applied to behavioural genetic research and its ethical implications. Therefore, this paper elucidates how behavioural genetic information can be distinguished from other types of genetic and non-genetic information and also synthesises the determinative significance of genetic factors for the development of human behavioural traits. Undertaking this analysis enables the ethical issues raised by this research to be debated in an appropriate context and indicates that separate policy considerations are warranted.

     

人口逆淘汰及其预防

对人口逆淘汰必须全面、动态地加以认识.必须阻止人口逆淘汰,提高人口质量,变"人口"为"人力".教育是关键措施,医疗卫生和环境改善十分重要,但决不能鼓励高学历人口多生育而限制农村人口的出生.     

Metaphors in behavioral genetics

Behavioral geneticists sometimes use metaphorsto describe the role of genes in humanbehavior. In this paper, five sample texts areanalyzed: a popular book, a textbook, ascientific review article, and two originalscientific articles representing differentapproaches in behavioral genetics. Metaphorsare found in all the different kinds of sampletexts, not only in the popular book and thetextbook. This suggests that metaphors are usednot only for rhetorical or pedagogical purposesbut play a more fundamental role in scientificunderstanding. In the sample texts, themetaphors tend to be antideterministic, i.e.,they do not imply genetic determinism butstress the interaction of multiple genes andmultiple environmental factors. No conclusioncan be drawn, however, as to whetherantideterminism is representative ofpresent-day behavioral geneticists in general.Certain historically important metaphors thatmay imply genetic determinism are qualified,avoided, or explicitly rejected. There aretensions between some of the metaphors, makingthem difficult to combine. All the metaphorsthat are used appear empirically apt, howeversometimes only with certain qualifications.     

Molecular geneticists and moral responsibility: “maybe if we were working on the atom bomb I would have a different argument”

Senior molecular geneticists were interviewed about their perceptions of the ethical and social implications of genetic knowledge. Inductive analysis of these interviews identified a number of strategies through which the scientists negotiated their moral responsibilities as they participated in generating knowledge that presents difficult ethical questions. These strategies included: further analysis and application of scientific method; clarification of multiple roles; negotiation with the public through public debate, institutional processes of funding, ethics committees and legislation; and personal responsibility.     

Is variability in mate choice similar for intelligence and personality traits? Testing a hypothesis about the evolutionary genetics of personality

This study tests the hypothesis presented by Penke, Denissen, and Miller (2007a) that condition-dependent traits, including intelligence, attractiveness, and health, are universally and uniformly preferred as characteristics in a mate relative to traits that are less indicative of condition, including personality traits. We analyzed between-culture mean standard deviations of preference ratings and rankings provided by nearly 10,000 people in 37 cultures for 18 characteristics in a potential mate. Contrary to the hypothesis, preferences for traits indicating agreeableness and conscientiousness were not more variable than preferences for intelligence, and preferences for traits indicating low neuroticism were more uniform than preferences for intelligence. Discussion addresses implications of these results for hypotheses about the evolutionary genetics of intelligence and personality.     

Human values: Genetic and environmental effects on five lexically derived domains and their facets

Whereas a substantial genetic component of Conservatism and Religiosity is well documented, there is little evidence with respect to the behavior genetics of other aspects of human values. A sample of 157 monozygotic and 74 dizygotic twins reared together received the Austrian Value Questionnaire (AVQ), which measures a broad variety of value domains and their facets, found by the lexical approach in the German language. Family resemblance of Intellectualism, Harmony, Materialism, and Conservatism was best explained by additive or dominance genetic and non-shared environmental effects, whereas the influence of the environment shared by twins was negligible. In contrast, Religiosity was transmitted by additive genetic, shared and non-shared environmental influences. At the level of facets, the Intellectualism and Harmony showed a homogenous etiology while Religiosity, Materialism, and Conservatism were etiologically heterogeneous.     

The protective role of higher intellectual functioning on violence in the household population of Great Britain

Despite compelling evidence of the effect of intelligence on delinquency and violent crime, there is limited data on its impact on population violence. We aimed to determine the association of categories of intelligence with violent behaviors in the general population and the extent of the impact of social class on these associations. A randomly selected sample of 14,738 individuals was derived from 2 British national surveys of adults aged 16 years and older. We measured self-reported violent behavior in the past 5 years, including: repetition, injury, violence while intoxicated, familial and extra-familial victim types and intimate partner violence. We examined the moderating role of social class on all outcomes. The increased risk of violence among persons of below average IQ was explained by social class at population level. High IQ had an overall protective effect on all outcomes except violence towards family members, irrespective of socio-economic circumstances. Social class moderated the association of IQ with violence by decreasing its protective effect among those in the lowest socio-economic positions. Our findings suggest that the association of IQ and violence is not linear but protective on population level. Social class has both an explaining and a moderating role in this association.     

In Defense of “Denial”: Difficulty Knowing When Beliefs Are Unrealistic and Whether Unrealistic Beliefs Are Bad

Bioethicists often draw sharp distinctions between hope and states like denial, self-deception, and unrealistic optimism. But what, exactly, is the difference between hope and its more suspect cousins? One common way of drawing the distinction focuses on accuracy of belief about the desired outcome: Hope, though perhaps sometimes misplaced, does not involve inaccuracy in the way that these other states do. Because inaccurate beliefs are thought to compromise informed decision making, bioethicists have considered these states to be ones where intervention is needed either to correct the person’s mental state or to persuade the person to behave differently, or even to deny the person certain options (e.g., another round of chemotherapy). In this article, we argue that it is difficult to determine whether a patient is really in denial, self-deceived, or unrealistically optimistic. Moreover, even when we are confident that beliefs are unrealistic, they are not always as harmful as critics contend. As a result, we need to be more permissive in our approach to patients who we believe are unrealistically optimistic, in denial, or self-deceived—that is, unless patients significantly misunderstand their situation and thus make decisions that are clearly bad for them (especially in light of their own values and goals), we should not intervene by trying to change their mental states or persuade them to behave differently, or by paternalistically denying them certain options (e.g., a risky procedure).     

Knowledge and Concern about STIs/HIV and Sociodemographic Variables Associated with Getting Tested for HIV Among the General Population in Spain

HIV testing is important in terms of prevention and treatment. However, HIV testing rates in the Spanish general population remains low. Therefore, HIV testing promotion constitutes a key issue. A high level of knowledge about HIV/AIDS is associated with having been tested for HIV. The general aim of this study was to determine the prevalence of people who had ever been tested for HIV in Spain. The sample consisted of 1,106 participants from the general population — 60.0% females and 40.0% males — aged between 17 and 55 years old. The assessment instruments were a questionnaire on sociodemographic data and HIV testing, a scale of knowledge about STIs and HIV/AIDS, and a scale of concern about STIs/HIV. Results showed that greater knowledge about STIs and HIV was associated with a greater likelihood of being tested for HIV (OR = .77; 95.0% CI = .73–.82; p < .05). In addition, higher concern about HIV/AIDS decreased the likelihood of not having been tested for HIV (OR = .87; 95.0% CI = .83–.92; p < .05). In fact, the higher participants concern about STIs was, the lower their likelihood of not having been tested for HIV was (OR = .87; 95.0% CI = .83–.91; p < .05). It is necessary to promote HIV testing in the general population as well as to consider their socio-demographic and psychological characteristics.