Children's memory and suggestibility about a distressing event: the role of children's and parents' attachment.

Our goal was to identify individual difference predictors of children's memory and suggestibility for distressing personally experienced events. Specifically, we examined children's and parents' attachment orientations and children's observable levels of distress, as well as other individual difference factors, as predictors of children's memory and suggestibility. Children (N=91) aged 3 to 6years were interviewed about inoculations received at medical clinics. For children whose parents scored as more avoidant, higher distress levels during the inoculations predicted less accuracy, whereas for children whose parents scored as less avoidant, higher distress levels predicted greater accuracy. Children with more rather than less positive representations of parents and older rather than younger children answered memory questions more accurately. Two children provided false reports of child sexual abuse. Implications for theory, research, and practice are discussed.

Learning to obtain reward, but not avoid punishment, is affected by presence of PTSD symptoms in male veterans: empirical data and computational model.

Post-traumatic stress disorder (PTSD) symptoms include behavioral avoidance which is acquired and tends to increase with time. This avoidance may represent a general learning bias; indeed, individuals with PTSD are often faster than controls on acquiring conditioned responses based on physiologically-aversive feedback. However, it is not clear whether this learning bias extends to cognitive feedback, or to learning from both reward and punishment. Here, male veterans with self-reported current, severe PTSD symptoms (PTSS group) or with few or no PTSD symptoms (control group) completed a probabilistic classification task that included both reward-based and punishment-based trials, where feedback could take the form of reward, punishment, or an ambiguous "no-feedback" outcome that could signal either successful avoidance of punishment or failure to obtain reward. The PTSS group outperformed the control group in total points obtained; the PTSS group specifically performed better than the control group on reward-based trials, with no difference on punishment-based trials. To better understand possible mechanisms underlying observed performance, we used a reinforcement learning model of the task, and applied maximum likelihood estimation techniques to derive estimated parameters describing individual participants' behavior. Estimations of the reinforcement value of the no-feedback outcome were significantly greater in the control group than the PTSS group, suggesting that the control group was more likely to value this outcome as positively reinforcing (i.e., signaling successful avoidance of punishment). This is consistent with the control group's generally poorer performance on reward trials, where reward feedback was to be obtained in preference to the no-feedback outcome. Differences in the interpretation of ambiguous feedback may contribute to the facilitated reinforcement learning often observed in PTSD patients, and may in turn provide new insight into how pathological behaviors are acquired and maintained in PTSD.

Respiratory and Cardiovascular Response during Electronic Control Device Exposure in Law Enforcement Trainees.

OBJECTIVE: Law enforcement represents a large population of workers who may be exposed to electronic control devices (ECDs). Little is known about the potential effect of exposure to these devices on respiration or cardiovascular response during current discharge. METHODS: Participants (N = 23) were trainees exposed to 5 s of an ECD (Taser X26(®)) as a component of training. Trainees were asked to volitionally inhale during exposure. Respiratory recordings involved a continuous waveform recorded throughout the session including during the exposure period. Heart rate was calculated from a continuous pulse oximetry recording. RESULTS: The exposure period resulted in the cessation of normal breathing patterns in all participants and in particular a decrease in inspiratory activity. No significant changes in heart rate during ECD exposure were found. CONCLUSION: This is the first study to examine breathing patterns during ECD exposure with the resolution to detect changes over this discrete period of time. In contrast to reports suggesting respiration is unaffected by ECDs, present evidence suggests that voluntary inspiration is severely compromised. There is no evidence of cardiac disruption during ECD exposure.

Behavioral inhibition and PTSD symptoms in veterans.

Behavioral inhibition (BI), a temperamental bias to respond to novel stimuli with avoidance behaviors, is a risk factor for posttraumatic stress disorder (PTSD). It is unclear whether BI accounts for additional variance in PTSD symptom severity beyond that accounted for by general anxiety. Here, 109 veterans (mean age 50.4 years, 9.2% female) provided self-assessment of PTSD symptoms, state and trait anxiety, combat exposure, and current (adult) and retrospective (childhood) BI. Adult BI was correlated with anxiety and PTSD symptom severity, especially cluster C (avoidance) symptoms, but not with combat exposure. A regression model including adult BI, state and trait anxiety, and combat exposure was able to correctly classify over 80% of participants according to presence or absence of severe PTSD symptoms. Because avoidance behaviors are a core component of PTSD, self-assessments of BI may be an important tool in understanding PTSD and potentially assessing vulnerability to the disorder.

Behaviorally inhibited temperament is associated with severity of post-traumatic stress disorder symptoms and faster eyeblink conditioning in veterans.

Prior studies have sometimes demonstrated facilitated acquisition of classically conditioned responses and/or resistance to extinction in post-traumatic stress disorder (PTSD). However, it is unclear whether these behaviors are acquired as a result of PTSD or exposure to trauma, or reflect preexisting risk factors that confer vulnerability for PTSD. Here, we examined classical eyeblink conditioning and extinction in veterans self-assessed for current PTSD symptoms, exposure to combat, and the personality trait of behavioral inhibition (BI), a risk factor for PTSD. A total of 128 veterans were recruited (mean age 51.2 years; 13.3% female); 126 completed self-assessment, with 25.4% reporting a history of exposure to combat and 30.9% reporting current, severe PTSD symptoms (PTSS). The severity of PTSS was correlated with current BI (R(2) = 0.497) and PTSS status could be predicted based on current BI and combat history (80.2% correct classification). A subset of the veterans (n = 87) also completed the eyeblink conditioning study. Among veterans without PTSS, childhood BI was associated with faster acquisition; veterans with PTSS showed delayed extinction, under some conditions. These data demonstrate a relationship between current BI and PTSS, and indicate that the facilitated conditioning sometimes observed in patients with PTSD may partially reflect personality traits such as childhood BI that pre-date and contribute to vulnerability for PTSD.

Cardiovascular evaluation of electronic control device exposure in law enforcement trainees: a multisite study.

OBJECTIVE: Occupational health risk with regard to training exercises is a relatively under studied domain for law enforcement officers. One potential health risk is exposure to electronic control devices (ECDs). METHODS: Seven different training facilities in six states participated. Law enforcement trainees (N = 118) were exposed to Taser International's (Scottsdale, AZ) X26 for up to 5 seconds. RESULTS: There was no evidence of cardiac or skeletal muscle breakdown. Exposure did not adversely affect electrocardiogram (ECG) morphology obtained 24 hours after exposure in 99 trainees. For two trainees with preexisting ECG abnormalities, ECG morphology differed in the post-ECD samples. CONCLUSIONS: The results from this large, multisite study suggest that, for most trainees, ECD exposure does not represent a significant health risk. Further investigation is warranted for cardiac vulnerability and potential interactions with ECD exposure.

Children's narratives and patterns of cardiac reactivity.

The present study examines the associations between narrative processing, narrative production, and cardiac rate and variability in children. Heart period (HP) and vagal tone (VT) were computed for fifty-eight 7-year-olds (29 males) during a resting baseline and during epochs in which the children listened to and completed a selected set of story-stems from the MacArthur Story-Stem Battery (I. Bretherton, D. Oppenheim, H. Buchsbaum, R. N. Emde, & the MacArthur Narrative Group, 1990). Significant decreases in HP and VT were observed between a resting baseline and epochs of story-stem presentation by the experimenter. In addition, HP was shorter and VT lower during children's narrative production to emotionally laden story-stems compared with narration to a neutral story-stem. Furthermore, narrative and cardiac responses to stories containing separation-reunion themes reflected increased emotional and cognitive load compared with responses to stories that did not contain such themes. Finally, children who showed VT suppression in response to emotion-laden stories produced more coherent and adaptive narratives compared to those of children who did not show VT suppression. The findings suggest interplay between the cognitive-emotional processes associated with narrative processing and production and cardiac activation patterns.