The Roman high-avoidance (RHA) and low-avoidance (RLA) rat lines/strains were established in Rome through bidirectional selection of Wistar rats for rapid (RHA) or extremely poor (RLA) acquisition of a two-way active avoidance task. Relative to RHAs, RLA rats exhibit enhanced threat sensitivity, anxiety, fear and vulnerability to stress, a passive coping style and increased sensitivity to frustration. Thus, RLA rats’ phenotypic profile falls well within the “internalizing” behavior spectrum. Compared with RLAs and other rat strains/stocks, RHAs present increased impulsivity and reward sensitivity, deficits in social behavior and attentional/cognitive processes, novelty-induced hyper-locomotion and vulnerability to psychostimulant sensitization and drug addiction. Thus, RHA rats’ phenotypes are consistent with a “disinhibiting externalizing” profile. Many neurobiological/molecular traits differentiate both rat lines/strains. For example, relative to RLA rats, RHAs exhibit decreased function of the prefrontal cortex (PFC), hippocampus and amygdala, increased functional tone of the mesolimbic dopamine system, a deficit of central metabotropic glutamate-2 (mGlu2) receptors, increased density of serotonin 5-HT2A receptors in the PFC, impairment of GABAergic transmission in the PFC, alterations of several synaptic markers and increased density of pyramidal immature dendrític spines in the PFC. These characteristics suggest an immature brain of RHA rats and are reminiscent of schizophrenia features like hypofrontality and disruption of the excitation/inhibition cortical balance. We review evidence supporting RLA rats as a valid model of anxiety/fear, stress and frustration vulnerability, whereas RHA rats represent a promising translational model of neurodevelopmental alterations related to impulsivity, schizophrenia-relevant features and comorbidity with drug addiction vulnerability.

Peer victimization is a developmentally salient stressor that elevates adolescents’ risk for anxiety disorders. However, modifiable mechanisms that explain this link and can be targeted via therapeutic interventions remain poorly understood. Drawing from psychobiological models implicating aberrant threat sensitivity in the development and maintenance of psychopathology, the current study investigated sensitivity to peer-related social threats as a mechanism underlying the association between peer victimization and anxiety. A sample of 197 dyads of early adolescents (Mage = 12.02; 46% female) and parents/guardians (Mage = 41.46; 90% female) completed online surveys assessing peer victimization, sensitivity to potential (i.e., ambiguous) social threats, and anxiety. Controlling for potentially confounding demographic and psychosocial factors, both self- and parent-reported peer victimization were positively associated with adolescent anxiety symptoms. Additionally, there were significant indirect effects from self- and parent-reported peer victimization to anxiety via social threat sensitivity. Supplemental analyses indicated unique effects of covert, but not overt, peer victimization on social threat sensitivity and anxiety. The findings provide initial evidence that peer victimization experiences lower adolescents’ threshold for interpreting threats in ambiguous social situations, which contributes to heightened anxiety. These results implicate social threat sensitivity as a potential therapeutic target for interrupting links from peer victimization to psychological distress.

Research finds that the perception that immigrants are culturally and economically threatening is associated with negative attitudes toward immigration. In a largely separate body of work, psychophysiological predispositions toward threat sensitivity are connected to a range of political attitudes, including immigration. This article draws together these two literatures, using a lab experiment to explore psychophysiological threat sensitivity and immigration attitudes in the United States. Respondents with higher threat sensitivity, as measured by skin conductance responses to threatening images, tend to be less supportive of immigration. This finding builds on our understanding of the sources of anti-immigrant attitudes.