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.     

PUNISHMENT IN HUMAN CHOICE: DIRECT OR COMPETITIVE SUPPRESSION?

This investigation compared the predictions of two models describing the integration of reinforcement and punishment effects in operant choice. Deluty's (1976) competitive-suppression model (conceptually related to two-factor punishment theories) and de Villiers' (1980) direct-suppression model (conceptually related to one-factor punishment theories) have been tested previously in nonhumans but not at the individual level in humans. Mouse clicking by college students was maintained in a two-alternative concurrent schedule of variable-interval money reinforcement. Punishment consisted of variable-interval money losses. Experiment 1 verified that money loss was an effective punisher in this context. Experiment 2 consisted of qualitative model comparisons similar to those used in previous studies involving nonhumans. Following a no-punishment baseline, punishment was superimposed upon both response alternatives. Under schedule values for which the direct-suppression model, but not the competitive-suppression model, predicted distinct shifts from baseline performance, or vice versa, 12 of 14 individual-subject functions, generated by 7 subjects, supported the direct-suppression model. When the punishment models were converted to the form of the generalized matching law, least-squares linear regression fits for a direct-suppression model were superior to those of a competitive-suppression model for 6 of 7 subjects. In Experiment 3, a more thorough quantitative test of the modified models, fits for a direct-suppression model were superior in 11 of 13 cases. These results correspond well to those of investigations conducted with nonhumans and provide the first individual-subject evidence that a direct-suppression model, evaluated both qualitatively and quantitatively, describes human punishment better than a competitive-suppression model. We discuss implications for developing better punishment models and future investigations of punishment in human choice.     

The just world hypothesis as an argumentative resource in debates about unemployment benefits

The concept of the “just world” is established as a key explanation for how people make sense of inequality so that those deemed to score high in belief in a just world are more likely to hold prejudicial beliefs and to blame people in poverty for their situations. However, this is an inadequate explanation for such complicated and controversial issues. To better understand talk about the just world and the controversial issue of the distribution of unemployment benefits (an issue of inequality), a discursive psychological approach to the just world is used. Therefore, a discourse analysis focusses on 2 feature length British televised discussions about benefit claimants called “The Big Benefit Row: Live” (Channel 5 3/2/2014) and “Benefits Britain: the Debate” (Channel 4 17/2/2014). The analysis demonstrates that people draw on both just and unjust world arguments simultaneously and also topicalise what counts as just so as to support their positions on unemployment benefits, rather than in the consistent way that just world theory would predict. It is therefore argued that the just world should be recast as a cultural value that facilitates arguments about benefits, rather than an internally held belief.     

Belief in a just world, teacher justice, and bullying behavior

The relation between school students' belief in a just world (BJW) and their bullying behavior was investigated in a questionnaire study. The mediating role of teacher justice was also examined. Data were obtained from a total of N = 458 German and Indian high school students. Regression analyses revealed that the more strongly students believed in a personal just world and the more they evaluated their teachers' behavior toward them personally to be just, the less bullying behavior they reported. Moreover, students with a strong BJW tended to evaluate their teachers' behavior toward them personally to be more just, and the experience of teacher justice mediated the relation between BJW and less bullying perpetration. This pattern of results was as expected and consistent across different cultural contexts. It persisted when neuroticism, sex, and country were controlled. The adaptive functions of BJW and implications for future school research are discussed.     

Belief in a just world and wellbeing in Indian schools

This study investigates the meaning of belief in just world (BJW) for students' subjective justice experiences with their parents and teachers and for students' subjective well-being. The hypotheses tested were that the more strongly students endorse BJW, the less the distress at school and depressive symptoms they experience. Two dimensions of BJW were assessed: personal BJW, reflecting the belief that events in one's own life are generally just, and general BJW, reflecting the belief that the world is basically a just place. The participants were 278 Indian students attending ten 10th grade classes at two private English-medium schools. The results showed that only the personal BJW, not the general BJW, was important in explaining justice experiences and wellbeing. The more the students endorsed the belief in personal just world, the more they felt treated justly by their teachers and their parents alike, and the less distress at school and depressive symptoms they experienced. In addition, teacher justice, but not parent justice, explained distress at school. Finally, the effect of personal BJW on depressive symptoms was partly mediated by both teacher and parent justice. This pattern of results persisted when class effects were controlled. Overall, this pattern of results emphasizes the importance of the individual and subjective experience of justice of the teacher behavior for adolescent wellbeing. Implications for further studies on BJW and wellbeing at school are discussed.     

Bion’s discovery of alpha function: Thinking under fire on the battlefield and in the consulting room

This paper has traced Bion’s discovery of alpha function and its subsequent elaboration. His traumatic experiences as a young tank commander in World War I (overlaid on, and intertwined with, childhood conflicts) gave him firsthand exposure to very painful emotions that tested his capacity to manage. Later, in the 1950s, after his analysis with Melanie Klein and marriage to Francesca Bion, he undertook the analysis of psychotic patients and learned how they disassembled their ability to know reality as a defense against unbearable emotional truths in their lives. This led Bion to identify an aspect of dreaming that was necessary in order for reality experience to be given personal meaning so that one may learn from experience. Simultaneous with working out this new theory of dreaming, Bion also revisited his World War I experiences that had remained undigested and all these elements coalesced into a selected fact – his discovery of alpha function. In subsequent writings, Bion explored the constituent factors of alpha function, including the container/contained relationship, the PS?D balance, reverie, tolerated doubt and other factors which I have termed the ‘Constellation for Thinking’.     

Perceptions of personal sex discrimination: the role of belief in a just world and situational ambiguity

The roles of belief in a just world (BJW) and discrimination against ones' group in perceptions of personal discrimination were examined. Female participants (n = 63) were personally discriminated against in a laboratory setting. We manipulated whether the experimenter appeared to discriminate against other participants, which presumably made the presence of personal discrimination less ambiguous, or did not appear to discriminate against others, which presumably made personal discrimination more ambiguous. In the no group discrimination condition, but not in the group discrimination condition, participants' perceptions of being personally discriminated against depended on individual differences in BJW: Women with a strong BJW perceived less personal discrimination than those with a weak BJW. Also, strong BJW women in the group discrimination condition perceived less personal discrimination than strong BJW women in the no group discrimination condition.     

Just world beliefs, causal beliefs, and acquaintance: Associations with stigma toward eating disorders and obesity

The current study investigated the relationship between just world beliefs and stigmatizing attitudes toward eating disorders and obesity. Further, the associations between stigma and causal beliefs, and between stigma and acquaintance with these conditions, were examined. Participants (n = 447) read four vignettes describing an individual with anorexia nervosa, bulimia nervosa, binge eating disorder, or obesity. After each vignette, participants completed questionnaires assessing stigmatizing attitudes, just world beliefs, causal beliefs, and acquaintance with the condition depicted in the vignette. Stronger just world beliefs were associated with greater stigma toward all three eating disorders, as well as obesity (rs ranging from −.11 to −.18). More stigmatizing attitudes were associated with greater attribution of individual responsibility for the development of the disorder. However, participants with personal experience or who knew someone with the depicted problem did not have lower stigma scores than those who did not. The current study suggests that justification ideologies such as just world beliefs and controllability beliefs may underlie the stigmatization of eating disorders and obesity. These findings provide support for stigma reduction efforts aimed at targeting justification ideologies and altering causal beliefs.     

Thyme to touch: Infants possess strategies that protect them from dangers posed by plants

Plants have been central to human life as sources of food and raw materials for artifact construction over evolutionary time. But plants also have chemical and physical defenses (such as harmful toxins and thorns) that provide protection from herbivores. The presence of these defenses has shaped the behavioral strategies of non-human animals. Here we report evidence that human infants possess strategies that would serve to protect them from dangers posed by plants. Across two experiments, infants as young as eight months exhibit greater reluctance to manually explore plants compared to other entities. These results expand the growing literature showing that infants are sensitive to certain ancestrally recurrent dangers, and provide a basis for further exploration.