5-HTTLPR X Stress in Adolescent Depression: Moderation by MAOA and Gender

Depression surges in adolescence, especially among girls. Most evidence indicates that the short allele of a polymorphism in the promoter region of the serotonin transporter gene (5-HTTLPR) interacts with stress to influence the onset of depression. This effect appears to be less robust in adolescents, particularly among boys, and may be moderated by other genetic polymorphisms. Seeking to explain the adolescent gender difference in depression, this study examined the effects of 5-HTTLPR (rs25531), the monoamine oxidase A-upstream variable number tandem repeat (MAOA-uVNTR), and negative life events (NLE). A community-based longitudinal sample of 309 adolescents reported depressive symptoms and NLE at ages 11, 13, and 15. 5-HTTLPR and MAOA-uVNTR genotypes were ascertained via buccal swabs. A significant four-way interaction of 5-HTTLPR, MAOA-uVNTR, NLE at age 13, and gender predicted depressive symptoms at age 15. Girls were most likely to exhibit elevated depressive symptoms when experiencing NLE if they possessed low-expression MAOA-uVNTR alleles and short 5-HTTLPR alleles, whereas low-expression MAOA-uVNTR alleles but long 5-HTTLPR alleles were implicated in boys. The results indicate that the commonly reported 5-HTTLPR by stress interaction for depression may be limited to individuals with low-expression MAOA-uVNTR alleles. These data also provide new evidence that the short allele of 5-HTTLPR confers susceptibility to stress differently for females compared with males.     

The effects of feedback in psychophysical tasks

Previous results of the reinforcement effects of feedback in psychophysical tasks have been interpreted as changes in the S’s response bias in the uncertain sensory state. The present study varied the percentage of feedback in a two-altemative loud-soft recognition task. The values of the probability of correct feedback were 1, .8, .6, .4, .2, and 0. The results indicated that Ss learned to respond to agree with the experimental feedback rather than with the actual cue presented on a trial. The probability of a response on Trial n +1 was highly dependent upon the response and feedback of Trial n only when the two trials were the same. It was concluded that feedback must influence the response probability vector associated with a given detection state.     

An easily built and inexpensive apparatus for generating electroconvulsive shock

An easily constructed and inexpensive apparatus for generating electroconvulsive shock is described. The wide range of shock level adjustment and reliability of operation make it an excellent piece of equipment to have in laboratories using electroconvulsive shock as an experimental tool for research on memory and memory storage processes.     

The effect of Pavlovian stimuli on the acquisition of a new response

Three experiments explored the effects of response dependent stimuli which have had different types of contingent relationships with positive reinforcement. Results showed consistent differences in the effects of response dependent appetitive Pavlovian CS + s, CS ? s, and truly random control (TRC) stimuli on the acquisition of a new response. These differences were shown in both a free operant and a discrete-trial learning situation. Appetitive Pavlovian CS?s consistently produced lower levels of responding than did TRC stimuli, even in an experimental situation free of possible contrast effects. The results of these experiments extended a contingency analysis of acquired associations to appetitive conditioning and provided a clear demonstration of a conditioned reinforcement effect against a variety of control procedures.     

On being both with us and against us: a normative conflict model of dissent in social groups.

Although past research has demonstrated a positive relationship between collective identification and normative conformity, there may be circumstances in which strongly identified members do not conform but instead choose to challenge group norms. This article proposes a normative conflict model, which distinguishes between nonconformity due to dissent (challenging norms to change them) and nonconformity due to disengagement (distancing oneself from the group). The normative conflict model predicts that strongly identified members are likely to challenge group norms when they experience conflict between norms and important alternate standards for behavior, in particular when they perceive norms as being harmful to the group. Data in support of the model are reviewed, mechanisms by which external variables may influence dissent in social groups are elaborated, and the model is linked to contemporary perspectives on collective identity.     

Interactions between Callous Unemotional Behaviors and Executive Function in Early Childhood Predict later Aggression and Lower Peer-liking in Late-childhood

Callous unemotional (CU) behaviors are linked to aggression, behavior problems, and difficulties in peer relationships in children and adolescents. However, few studies have examined whether early childhood CU behaviors predict aggression or peer-rejection during late-childhood or potential moderation of this relationship by executive function. The current study examined whether the interaction of CU behaviors and executive function in early childhood predicted different forms of aggression in late-childhood, including proactive, reactive, and relational aggression, as well as how much children were liked by their peers. Data from cross-informant reports and multiple observational tasks were collected from a high-risk sample (N = 240; female = 118) at ages 3 and 10 years old. Parent reports of CU behaviors at age 3 predicted teacher reports of reactive, proactive, and relational aggression, as well as lower peer-liking at age 10. Moderation analysis showed that specifically at high levels of CU behaviors and low levels of observed executive function, children were reported by teachers as showing greater reactive and proactive aggression, and were less-liked by peers. Findings demonstrate that early childhood CU behaviors and executive function have unique main and interactive effects on both later aggression and lower peer-liking even when taking into account stability in behavior problems over time. By elucidating how CU behaviors and deficits in executive function potentiate each other during early childhood, we can better characterize the emergence of severe and persistent behavior and interpersonal difficulties across development.     

Does Acquisitive Self‐Presentation in Personality Self‐Ratings Enhance Validity? Evidence from two experimental field studies

The aim of the present research was to demonstrate that acquisitive self‐presentation in personality scales is not a barrier to their criterion‐related validities in human resource contexts, but rather a means to improve them. A pilot study (Study 1) with 96 job incumbents provided preliminary positive evidence. In Study 2, in the experimental group (n=99), the instructions asked job incumbents to work on a Big‐Five personality inventory (BFI‐K) as if they took part in a personnel selection procedure for a personally very attractive position. In the control group (n=93) of Study 2, job incumbents were asked to answer the inventory items honestly. As expected, the correlation between the self‐ratings of the motive to get along (i.e., which comprises emotional stability, conscientiousness, and agreeableness) and contextual performance assessments was significantly higher in the experimental group than in the control group in Study 2. Additionally, the correlation between the self‐ratings of the motive to get ahead (i.e., which comprises extraversion and openness to experience) and task performance and leadership assessments was significantly higher in the experimental group than in the control group in Study 2. It is proposed that responding to a personality inventory in a human resource decision situation should be conceptualized as a workplace simulation.