Would you be happier if you moved more? Physical activity focusing illusion

Current Psychology - Research shows that individuals who are more physically active also report greater happiness. However, subjective well-being is prone to cognitive biases. For instance, people...     

Depressive symptomatology during pregnancy: evidence for an association with decreased fetal growth in pregnancies of lower social class women.

The relationship between depressive symptom scores on the Center for Epidemiological Studies Depression Scale (CES-D; L. S. Radloff, 1977) at each trimester of pregnancy and a decrement in either fetal growth or gestational duration was evaluated among 666 pregnant women. There was no association overall, but among 222 women from lower occupational status households, each unit increase on the CES-D at 28 weeks gestation was associated with a reduction of 9.1 g (95% confidence interval [CI] = -16.0, -2.3) in gestational-age-adjusted birth weight. When missing data were multiply imputed, the estimate was -4.6 g (95% CI = - 10.7, 1.5). CES-D score was unrelated to fetal growth or gestational duration in analyses among other potentially high-risk subgroups: smokers, women with a history of adverse outcome, and women with social vulnerabilities. These results raise the possibility that among lower status women, depressive mood may be associated with restricted fetal growth.     

An Open Trial of an Acceptance-Based Behavioral Intervention for Weight Loss

Innovative approaches are urgently needed to improve behavioral treatment for weight loss. The weight regain that is so common after treatment may be a result of an environment that makes it challenging to adhere, long-term, to a dietary and physical activity regimen. This study was designed to test, via a 12-week open trial, the preliminary feasibility, acceptability, effectiveness, and possible mechanisms of action of a behavioral treatment that was modified to incorporate acceptance-based therapy components designed to (a) bolster participants’ commitment to behavior change, (b) build distress-tolerance skills, and (c) promote mindful awareness of eating behaviors and goals. Participants (n = 29) were overweight or obese women. Among completers (n = 19; 34% attrition), weight loss averaged 6.6% of body weight at posttreatment and 9.6% at 6-month follow-up (n = 14; 52% attrition). Intention-to-treat weight losses were 4.5% at posttreatment and 6.6% at 6-month follow-up. Psychological variables targeted by the intervention (e.g., cognitive restraint, disinhibition, urge-related eating behavior, emotional eating, eating-related experiential acceptance, mindfulness and motivation) changed in the expected directions, and many of these changes were consistent with decreases in weight loss. Moreover, despite the limitations of the single-group design, this pilot study demonstrated the preliminary feasibility, acceptability, and effectiveness of a novel, acceptance-based behavioral treatment for obesity. One potential implication is that behaviorally based weight loss interventions might be improved by overlaying an acceptance-based framework.     

Inspecting visual mental images: Can people “see” implicit properties as easily in imagery and perception?

Can people “see” previously unnoticed properties in objects that they visualize, or are they locked into the organization of the pattern that was encoded during perception? To answer this question, we first asked a group to describe letters of the alphabet and found that some properties (such as the presence of a diagonal line) are often mentioned, whereas others (such as symmetry) are rarely if ever mentioned. Then we showed not only that other participants could correctly detect both kinds of properties in visualized letters, but also that the relative differences in the ease of detecting these two types of properties are highly similar in perception (when the letters are actually visible) and imagery (when the letters are merely visualized). These findings provide support for the view that images can be reinterpreted in ways much like what occurs during perception and speak to the wider issue of the long-standing debate about the format of mental images.     

Leader emergence: the case of the narcissistic leader

These studies investigate whether individuals with high narcissism scores would be more likely to emerge as leaders during leaderless group discussions. The authors hypothesized that narcissists would emerge as group leaders. In three studies, participants completed personality questionnaires and engaged in four-person leaderless group discussions. Results from all three studies reveal a link between narcissism and leader emergence. Studies 1 and 2 further reveal that the power dimension of narcissism predicted reported leader emergence while controlling for sex, self-esteem, and the Big Five personality traits. Study 3 demonstrates an association between narcissism and expert ratings of leader emergence in a group of executives. The implications of the propensity of narcissists to emerge as leaders are discussed.     

Preliminary evaluation of an after-school resistance training program for improving physical fitness in middle school-age boys

Most after-school physical activity programs for youth focus on aerobic games and activities. The purpose of this study was to evaluate the efficacy of an after-school resistance training program on improving the physical fitness of middle school-age boys. 22 boys (M = 13.9 yr., SD = .4 yr.) participated in a periodized, multiple-set, 9-wk. (2x/week) resistance training program. All subjects were pre- and post-tested on their 10-repetition maximum squat, 10-repetition maximum bench press, vertical jump, medicine ball toss, flexibility, and also percentage of body fat and the progressive aerobic cardiovascular endurance run (PACER). Statistical analysis indicated that subjects significantly improved performance on the squat (19%), bench press (15%), flexibility (10%), vertical jump (5%), medicine ball toss (12%), and the PACER (36%). Although this design minus a control group limits interpretation, this after-school resistance-training program can improve muscular fitness and cardiovascular fitness in boys and should be replicated with appropriate experimental controls.     

Hierarchical, job content, and double plateaus: A mixed-method study of stress, depression and coping responses

Hierarchically, job content, and double plateaued employees from a variety of industries were surveyed regarding their experiences. Plateau-specific stress was higher than the stress experienced by the general population. Plateaued employees also reported more depression than the general population. Double plateaued employees reported higher depression than hierarchically plateaued employees. Content analysis revealed 27 distinct coping strategies reported by employees, representing 7 coping meta-themes. The most frequently occurring meta-themes were Discuss Problem, Job Withdrawal, and Mental Coping. Hierarchically plateaued employees reported slightly greater use of Mental Coping strategies than job content and double plateaued employees.     

Categorization and affect: evidence for intra-hemispheric interactions

Both emotional reactivity and categorization have long been studied within the framework of hemispheric asymmetry. However, little attempt has been made to integrate both research areas using any form of neuropsychological research, despite behavioral data suggesting a consistent relationship between affective and categorization processes. The primary goal of the current study was to examine the possibility of a laterally mediated interaction between emotional reactivity and the cognitive process of categorization. Using a split visual fields categorization task combined with affect inducing procedures, we hypothesized that the relationship between state affect and categorization would be dependent on the nature of state affect and on the hemisphere targeted. Results offered support for this hypothesis, showing that state affect related changes in categorization appeared only in the hemisphere commonly associated with both a specific affective state and categorization strategy employed. Findings are discussed in terms of possible evidence for a hemispheric arousal effect underlying the relationship between affect and categorization.     

Opposing actions of chronic Delta9-tetrahydrocannabinol and cannabinoid antagonists on hippocampal long-term potentiation

Memory deficits produced by marijuana arise partly via interaction of the psychoactive component, Delta(9)-tetrahydrocannabinol (Delta(9)-THC), with cannabinoid receptors in the hippocampus. Although cannabinoids acutely reduce glutamate release and block hippocampal long-term potentiation (LTP), a potential substrate for learning and memory, the consequences of prolonged exposure to Delta(9)-THC for hippocampal function are poorly understood. Rats were injected with Delta(9)-THC (10 mg/kg, i.p., q.d.) for 1, 3, or 7 d, and electrophysiological recordings were performed in hippocampal slices 1d after the final injection. At this time, Delta(9)-THC was undetectable in hippocampus using liquid chromatography-mass spectrometry (LC-MS). Hippocampal LTP generated using high-frequency (HFS) or theta burst stimulation was not observed in brain slices from the 7-d Delta(9)-THC-treated animals. Delta(9)-THC also blocked HFS-LTP after 3 d, but not 1 d of treatment. The complete blockade of LTP persisted for 3 d after the last Delta(9)-THC injection, and full reversal of the LTP deficit was not observed up to 14 d following Delta(9)-THC withdrawal. The cannabinoid antagonist AM251 (2 mg/kg), administered before each Delta(9)-THC injection prevented the blockade of LTP, and 7-d treatment with AM251 alone significantly increased the level of LTP. Chronic Delta(9)-THC also produced tolerance to the inhibition of synaptic GABA, but not glutamate release by the agonist WIN55,212-2. These data define consequences of repeated Delta(9)-THC exposure for synaptic plasticity in the hippocampus that may help explain memory impairments in humans following chronic marijuana use.