Revisiting places passed: sensitization of exploratory activity in rats with hippocampal lesions

We examined the involvement of the hippocampus in short-term changes in exploratory behaviour in an open field (Experiment 1) and experimental contexts (Experiment 2). In Experiment 1, rats with excitotoxic lesions of the hippocampus were more likely to revisit recently visited zones within the open field than were control rats. Similarly, in Experiment 2 rats with hippocampal lesions showed greater exploration of a context that they had recently explored than a context that they had less recently explored. This short-term sensitization effect was not evident in control rats. These findings are consistent with the suggestion that the recent presentation of a stimulus has two opposing effects on behaviour, sensitization, and habituation, and that hippocampal lesions disrupt the short-term process responsible for habituation, but not that responsible for sensitization.     

Beyond Compliance: Mother–Child Joint Action During a “Do” Task

Much of the literature on parent-toddler interactions does not account for the lack of independence in data. This investigation used a theory and method appropriate for examining the moment-to-moment patterns of joint actions between mothers and toddlers during a “do” task. Using contextual action theory to guide a mixture of methods, we observed and described the joint goal-directed series of actions of mothers and their toddlers as well as mothers’ intentions, meanings, and emotions they ascribed to their actions. Additionally, the associations between the patterns of joint mother-toddler actions and children’s negative emotionality were examined. Thirty mothers and their children participated in the study. Data collection included video-recorded activity, video recall interviews, and self-report questionnaires. Quantitative and qualitative analysis of the data revealed that (a) children were mostly engaged in the task alongside with their mothers’ on-going involvement; (b) mothers attributed a range of meanings to their interactions with their children; and (c) mothers’ perceptions of their toddlers’ dimensions of emotional negativity were associated with the organization of dyads’ joint goal directed actions—both when children were engaged in the task or self-focused.     

Precipitating Circumstances of Suicide among Active Duty U.S. Army Personnel Versus U.S. Civilians, 2005–2010

To help understand suicide among soldiers, we compared suicide events between active duty U.S. Army versus civilian decedents to identify differences and inform military prevention efforts. We linked 141 Army suicide records from 2005 to 2010 to National Violent Death Reporting System (NVDRS) data. We described the decedents’ military background and compared their precipitators of death captured in NVDRS to those of demographically matched civilian suicide decedents. Both groups commonly had mental health and intimate partner precipitating circumstances, but soldier decedents less commonly disclosed suicide intent.     

An Analysis of Intrinsicality

The leading account of intrinsicality over the last thirty years has arguably been David Lewis's account in terms of perfect naturalness. Lewis's account, however, has three serious problems: i) it cannot allow necessarily coextensive properties to differ in whether they are intrinsic; ii) it falsely classifies non‐qualitative properties like being Obama as non‐intrinsic; and iii) it is incompatible with a number of metaphysical theories that posit irreducibly non‐categorical properties. I argue that, as a result of these problems, Lewis's account should be rejected and replaced with an alternative account, which also analyses intrinsicality in terms of perfect naturalness, but which avoids these problems.     

Effects of Weight Cue Reactivity on Self-Report Measures of Body Dissatisfaction

Research has shown that answers on self-report measures can be influenced by a participant’s awareness of information regarding the study (“reactivity”). There exists a gap in the literature regarding weight cue reactivity on self-report measures of body dissatisfaction (BD). This type of reactivity involves exposing participants to information regarding their height, weight, or body mass index (BMI). Ninety-Nine participants (45.5 % female, mean age = 20.17, SD = 3.08) were randomly assigned to one of three conditions: proximal weight cue (being weighed before completing measures); distal weight cue (knowledge of impending measurement following questionnaire completion); and no weight cues (control), all before measures of BD. Perceived body size and BD were measured using the Stunkard Figure Rating Scale. Two separate ANCOVAs revealed a significant main effect for condition on self-reported perceived body size F [2,92] = 5.22, p = 0.01, η2 = 0.10, as well as on BD, F [2,92] = 9.46, p < 0.001, η2 = 0.17, while controlling for BMI. Both proximal and distal cues elicited elevated BD; only proximal cues elicited self-reported perceived body size. These results quantify the impact of weight cue reactivity effects on self-report measures and suggest that researchers and/or clinicians collect answers on such measures prior to anthropometric data.