The overall goal of the current study was to determine if perceptions of popular peers' relationally aggressive (PPSRA) and prosocial behaviors (PPSP) were related to engagement in these behaviors in a sample of emerging adults. This study also investigated if these associations were moderated by sympathetic nervous system (SNS) and parasympathetic nervous system (PNS) reactivity to peer stress and gender. Although a significant amount of research suggests that aggressive behaviors can be socialized by peers (e.g., Molano, Jones, Brown, & Aber, 2013), there is a dearth of work that has examined relational forms of aggression that tend to be more salient for females and more positive, prosocial behaviors. Further, given that some research suggests that perceptions about how peers behave, regardless of peers' actual behavior, influences individual behavior (e.g., Song et al., 2012), the current study investigated the impact of perceptions of peer behavior. Additionally, research suggests that some individuals are more susceptible to peer influence than others (e.g., Steinberg & Monahan, 2007). Biological Sensitivity to Context (BSC) has been offered as a potential explanation for this differential susceptibility to peer influence (e.g., Boyce & Ellis, 2005). BSC theory postulates that individuals with a heightened stress response are more malleable to environmental influence, for better or worse; therefore, the interaction between PNS reactivity to stress (measured by respiratory sinus arrhythmia [RSA-R]) and SNS reactivity (measured by skin conductance level [SCL-R]) to a relational stressor was examined as a moderator in the current study. Gender was also examined as a moderator. 200 emerging adults aged 18-23 years (70% female; Mage= 19.04) were recruited from introductory psychology courses at a Northeastern public university. Participants' SCL-R and RSA-R were assessed during a laboratory stress protocol during which they recounted an experience of relational stress. PPSRA, PPSP, and gender were gathered via self-report. Findings suggest that PPSRA was positively related to self-reported engagement in relational aggression and, similarly, PPSP was positively associated with self-reported engagement in prosocial behavior. However, neither interactions between RSA-R and SCL-R nor gender significantly moderated these relationships. Follow-up analyses indicated PPSP was significantly, negatively related to engagement in relational aggression for males only. Findings suggest that perceptions about the behavior of popular peers do have an important influence on college students' behavior and highlight future directions for research into the factors that may modify this relationship.

Risky alcohol use increases the risk of certain crimes such as drunk driving, spousal abuse and fighting. Around 60% of an individual’s alcohol use is attributable to genetic influences, however little is known regarding the specific genes that are involved in increasing the risk of risky alcohol use. Recent theories posit that some genes are so called susceptibility genes, meaning that carriers of certain genes or alleles are more susceptible both to positive and negative environments. The aim of the present study was to examine main and interaction effects of a possible susceptibility gene (ANKK1, which in previous research has been found to be related to risky alcohol use), and victimization as a negative environmental factor and parent-child relationship as a positive factor. Data were drawn from the RESUME project, and in the present study, 1.800 participants were included (47% males; 53% females; mean age of 22.15 years). Results showed no statistically significant main or interaction effect for ANKK1, but a statistically significant main effect was found for victimization and parent-child relationship. In conclusion, future research should include a larger sample size and use participants diagnosed with alcohol dependency. In addition, the susceptibility properties of ANKKI needs to be further examined, as the results from the present study indicate that ANKK1 is not a susceptibility gene. / Riskfylld alkoholkonsumtion kan öka risken för att vissa brott begås, såsom rattfylleri, partnervåld och slagsmål. Forskning har visat att omkring 60% av en individs alkoholkonsumtion kan förklaras av genetik, men det finns lite forskning kring just vilka gener som ökar risken för alkoholism. Nya teorier tror att vissa gener är så kallade sårbarhetsgener, vilket innebära att individer som bär på dessa gener eller särskilda alleler är mer sårbara för både positiva och negativa miljöfaktorer. Syftet med den nuvarande studien var att undersöka huvud-och interaktionseffekter av en potentiell sårbarhetsgen (ANKK1, som tidigare forskning visat har en påverkan på riskfylld alkoholkonsumtion), med utsatthet som den negativa faktorn och barn-föräldrarelation som den positiva faktorn. Data i form av enkätsvar och DNA prov från RESUME studien användes för den nuvarande studien, där 1,800 deltagare inkluderades (47% män; 53% av kvinnor; medelålder = 22.15). Resultaten visade inte på någon statistiskt signifikant huvud-eller interaktionseffekt för ANKKI, men det fanns en statistiskt signifikant huvudeffekt för utsatthet och barn-föräldrarelation. Slutsatsens som dras är att framtida studier bör fokusera på att ha ett större urval och använda sig av deltagare som är diagnosticerade med alkoholmissbruk. Utöver det bör framtida forskning fortsätta undersöka om ANKK1 är en sårbarhetsgen, eftersom resultaten från denna studie visar att den inte är en sårbarhetsgen.