Objective Prior research indicates that different types of childhood maltreatment frequently co-occur and confer risk for adulthood intimate partner violence (IPV). However, it is unknown whether the risk of IPV is due to specific type(s) of maltreatment or to their shared association or both. Although these competing explanations have different implications for intervention, they have never been evaluated empirically. Method Data were drawn from a nationally representative survey of 34,653 US adults, the 2004–2005 National Epidemiologic Survey on Alcohol and Related Conditions (NESARC). Structural equation modeling was used to simultaneously examine the shared and specific effects of five types of childhood maltreatment (i.e., sexual abuse, physical and emotional abuse and neglect) on the risk of different IPV behaviors (i.e., perpetration, victimization and reciprocal violence). Analyses were stratified by sex and adjusted for sociodemographic characteristics (i.e., age, personal income, educational background and race/ethnicity). Results Most types of childhood maltreatment increased the risk of victimization, perpetration and reciprocal violence. Effects of maltreatment types on each IPV behavior were exerted mostly through a latent factor representing the shared effect across all different types of maltreatment in both sexes (CFI=0.990, TLI=0.990, RMSEA=0.023), although sexual abuse had an additional effect on victimization. Conclusions Because childhood maltreatment types increase the risk of each intimate partner violence behavior mainly through a general maltreatment dimension, underlying biological and developmental-ecological mechanisms should be considered important targets of prevention for both victimization and perpetration of abuse in adult relationships.

Empathy and vicarious learning of fear are increasingly understood as separate phenomena, but the interaction between the two remains poorly understood. We investigated how social (vicarious) fear learning is affected by empathic appraisals by asking participants to either enhance or decrease their empathic responses to another individual (the demonstrator), who received electric shocks paired with a predictive conditioned stimulus. A third group of participants received no appraisal instructions and responded naturally to the demonstrator. During a later test, participants who had enhanced their empathy evinced the strongest vicarious fear learning as measured by skin conductance responses to the conditioned stimulus in the absence of the demonstrator. Moreover, this effect was augmented in observers high in trait empathy. Our results suggest that a demonstrator's expression can serve as a "social" unconditioned stimulus (US), similar to a personally experienced US in Pavlovian fear conditioning, and that learning from a social US depends on both empathic appraisals and the observers' stable traits.

Treponema denticola and Porphyromonas gingivalis have been associated with human adult severe periodontitis. In this study, we quantified these putative pathogens in subgingival plaque samples collected from 74 Fijians, 74 Colombians and 73 U.S. Americans stationed at the Multinational Force and Observers encampment in the Sinai Desert, Egypt. A contingency table of T. denticola and P. gingivalis frequency revealed a highly significant synergistic relationship. We discovered that the occurrence of T. denticola apparently requires the presence of P. gingivalis. This represents the first observation of a synergistic relationship between these putative oral pathogens associated with adult severe periodontal disease.

Prior research indicates that childhood maltreatment and impulsivity increase the risk for different types of violence, including violent behaviors directed toward the self and others. However, it is not known whether childhood maltreatment and impulsivity have independent effects on different violent behaviors. Therefore, this study examined the differential effects of childhood maltreatment and impulsivity on interpersonal violence, suicide attempts, and self-injury. Data were drawn from a nationally representative survey of 34,653 US adults, the 2004-2005 National Epidemiologic Survey on Alcohol and Related Conditions (NESARC). Structural equation modeling was used to simultaneously examine the shared and specific effects of five types of childhood maltreatment and impulsivity on the risk of different violent behaviors (i.e. interpersonal violence, suicide attempts, and self-injury). Analyses were stratified by gender and adjusted for age and ethnicity. Impulsivity and childhood maltreatment independently increased the risk of suicide attempt, self-injury, and interpersonal violence. Childhood maltreatment had stronger effects on violence directed towards the self than on interpersonal violence in both genders, while impulsivity had a stronger effect on self-injury than on suicide attempt or interpersonal violence in men. These findings indicate that childhood maltreatment and impulsivity relate differently to the risk of different types of violence.