The Effects of Acute Alcohol Intoxication and Self-Focused Rumination on Triggered Displaced Aggression

An experiment simultaneously examined the effects of acute alcohol intoxication and self-focused rumination on triggered displaced aggression. An ethnically diverse sample of 97 young adult participants (41 men, 56 women) were recruited from a university community and surrounding area. Participants were provoked by an experimenter, randomly assigned to a 2 (alcohol, sober)?×?2 (rumination, distraction)?×?2 (trigger, no trigger) between-participants design, and then given an opportunity to aggress against an undeserving other who was either completely innocent or slightly annoying. Self-focused rumination increased displaced aggression only when participants were triggered by the slightly annoying participant. Alcohol independently augmented aggression.     

The effects of alcohol and the salience of aggressive cues on triggered displaced aggression

Alcohol increases the aggression-augmenting effects of provocation. Theories of alcohol and aggression suggest that impaired cognitive processing induced by acute intoxication leads individuals to process aggression-inducing social cues differently depending on whether they are high or low in salience. We examined the effects of intoxication and aggressive cue salience within the triggered displaced aggression paradigm. An ethnically diverse sample of 74 primarily young adult participants (40 men and 34 women; M=23.28, SD=3.14 years) were recruited from the university community and surrounding area. All participants were provoked by an experimenter, randomly assigned to a 2 (alcohol condition: alcohol vs. placebo) x 2 (trigger salience: high vs. low salience) between-subjects design, and then given the opportunity to aggress against the undeserving triggering agent. As expected, intoxication combined with a salient triggering cue elicited the most displaced aggression among all conditions. These results provide the first evidence that the effect of alcohol on triggered displaced aggression is moderated by the salience of the triggering event.     

Effects of exposure of mice to hindlimb unloading on leukocyte subsets and sympathetic nervous system activity

The hindlimb unloading (HU) rodent model was developed to simulate some of the aspects of spaceflight conditions. Our previous studies showed that exposure to HU for 48 h (h) followed by bacterial challenge, reduces the ability of mice to resist infection. The purpose of this study was to investigate the physiological changes in mice during the 48 h of exposure to HU to understand the mechanisms involved in the increased susceptibility to infection observed in mice subjected to these conditions. Female Swiss Webster mice were hindlimb-unloaded during 48 h. Blood samples, spleen and peritoneal cells were removed before and after 18 or 48 h of HU-exposure. Leukocyte subset analysis was performed in spleen and peritoneal cells by flow cytometry, and catecholamine levels were measured in plasma and whole spleen by a catecholamine enzyme immunoassay. Catecholamine levels measured in plasma and spleen were significantly greater in mice exposed to HU compared to control. This increase coincided with significant reductions in spleen size in the HU group. Flow cytometric analyses showed a significant reduction of splenic CD19 + B-cells and NK1.1+ cells in mice exposed to HU with a concomitant increase in T-cells. These results suggest that exposure to HU increases the activity of the sympathetic nervous system (SNS) and induces lymphocyte sub-population changes that may contribute to the deregulation of immunity seen in mice exposed to HU and, more importantly may predispose the otherwise healthy host to the subsequent reduced ability to resist infections.