Psychometric assessment of the Mindful Attention Awareness Scale (MAAS) among Chinese adolescents

The Mindful Attention Awareness Scale (MAAS) has the longest empirical track record as a valid measure of trait mindfulness. Most of what is understood about trait mindfulness comes from administering the MAAS to relatively homogenous samples of Caucasian adults. This study rigorously evaluates the psychometric properties of the MAAS among Chinese adolescents attending high school in Chengdu, China. Classrooms from 24 schools were randomly selected to participate in the study. Three waves of longitudinal data (N = 5,287 students) were analyzed. MAAS construct, nomological, and incremental validity were evaluated as well as its measurement invariance across gender using latent factor analyses. Participants' mean age was 16.2 years (SD = 0.7), and 51% were male. The 15-item MAAS had adequate fit to the one-dimensional factor structure at Wave 1, and this factor structure was replicated at Wave 2. A 6-item short scale of the MAAS fit well to the data at Wave 3. The MAAS maintained reliability (Cronbach's α = .89-.93; test-restest r = .35-.52), convergent/discriminant validity, and explained additional variance in mental health measures beyond other psychosocial constructs. Both the 15- and 6-item MAAS scales displayed at least partial factorial invariance across gender. The findings suggest that the MAAS is a sound measure of trait mindfulness among Chinese adolescents. To reduce respondent burden, the MAAS 6-item short-scale provides an option to measure trait mindfulness.     

Adult mice maintained on a high-fat diet exhibit object location memory deficits and reduced hippocampal SIRT1 gene expression

Mounting evidence has established that diet-induced obesity (DIO) is associated with deficits in hippocampus-dependent memory. The bulk of research studies dealing with this topic have utilized rats fed a high-fat diet as an experimental model. To date, there has been a paucity of research studies that have established whether the memory deficits exhibited in DIO rats can be recapitulated in mice. Moreover, the majority of experiments that have evaluated memory performance in rodent models of DIO have utilized memory tests that are essentially aversive in nature (i.e., Morris water maze). The current study sought to fill an empirical void by determining if mice maintained on a high-fat diet exhibit deficits in two non-aversive memory paradigms: novel object recognition (NOR) and object location memory (OLM). Here we report that mice fed a high-fat diet over 23 weeks exhibit intact NOR, albeit a marked impairment in hippocampus-dependent OLM. We also determined the existence of corresponding aberrations in gene expression within the hippocampus of DIO mice. DIO mice exhibited significant reductions in both SIRT1 and PP1 mRNA within the hippocampus. Our data suggest that mice maintained on a high-fat diet present with impaired hippocampus-dependent spatial memory and a corresponding alteration in the expression of genes that have been implicated in memory consolidation.     

Learning strategy is influenced by trait anxiety and early rearing conditions in prepubertal male, but not prepubertal female rats

Rodents solve dual-solution tasks that require navigation to a goal by adopting either a hippocampus-dependent place strategy or a striatum-dependent stimulus-response strategy. A variety of factors, including biological sex and emotional status, influence the choice of learning strategy. In these experiments, we investigated the relationship between learning strategy and anxiety level in male and female rats prior to the onset of puberty, before the activational effects of gonadal hormones influence these processes. In the first experiment, prepubertal male rats categorized as high in trait anxiety at 26days of age exhibited a bias toward stimulus-response strategy at 28days of age, whereas age-matched females exhibited no preference in strategy regardless of anxiety level. In the second experiment, male and female rats were separated from their dams for either 15 or 180min per day during the first 2weeks of life and tested on a battery of anxiety and cognitive tasks between 25 and 29days of age. Prolonged maternal separations for 180min were associated with impaired spatial memory on a Y-maze task in both prepubertal males and females. Furthermore, prolonged maternal separations were linked to elevated anxiety and a bias for stimulus-response strategy in prepubertal males but not females. Alternatively, brief separations from dams for 15min were associated with intact spatial memory, lower levels of anxiety, and no preference for either learning strategy in both sexes. These results provide evidence of sex-specific effects of trait anxiety and early maternal separation on the choice of learning strategy used by prepubertal rodents.     

There’s an App for that: The Uses and Gratifications of Online Social Networks for Gay Men

This essay is an exploratory study of the uses and gratifications of social networking applications and sites widely utilized by gay men. Based on findings from six different focus groups and intercept interviews with gay and bisexual men, this essay explores the motivations and perceived benefits of social networking sites that allow for the creation of a virtual community of sexual minorities. This paper also considers these technological developments as part of a larger history of gay men communicating with other gay men within a culture where talk about homosexuality is closely policed and often restricted. Through a uses and gratifications approach, this essay discusses the needs and motivations that bring gay men online to social network sites, how they manage multiple identities online and the resulting gratifications of their online activity.     

Diagnosis of ADHD in Adults: What Is the Appropriate DSM-5 Symptom Threshold for Hyperactivity-Impulsivity?

Objective: To empirically identify the appropriate symptom threshold for hyperactivity-impulsivity for diagnosis of ADHD in adults. Method: Participants were 88 adults (M [SD] age = 41.69 [11.78] years, 66% female, 16% minority) meeting formal DSM-IV criteria for ADHD combined or predominantly inattentive subtypes based on a structured diagnostic interview keyed to DSM-IV (Conners' Adult ADHD Diagnostic Interview for DSM-IV [CAADID]). All participants also completed the Conners' Adult ADHD Rating Scale (CAARS), which was normed on the general adult population and includes subscales for DSM-IV inattentive and DSM-IV hyperactive-impulsive symptoms. A T-score threshold of 65 (at least 1.5 SD above population mean) on the CAARS DSM-IV hyperactive-impulsive dimension was used to identify participants with empirically elevated symptom severity. Results: Of 88 participating adults, 48 (55%) had a T-score of at least 65 (1.5 SD) on the CAARS DSM-IV Hyperactive-Impulsive scale. Of these, only 25 (52%) met the DSM-IV cutoff of six hyperactive-impulsive symptoms on the CAADID. Thus, approximately half of those who reported empirically elevated hyperactive-impulsive complaints on the CAARS did not concurrently meet the six-symptom DSM-IV cutoff on the CAADID. An alternative cutoff of four hyperactive-impulsive symptoms on the CAADID captured 39 (81%) cases identified by the CAARS. Conclusion: In adults, mandating at least six hyperactive-impulsive symptoms excludes a significant percentage (almost half) of adults who are at least 1.5 SD above the population mean on a dimensional measure of hyperactivity-impulsivity. These data provide a compelling basis for lowering the symptom threshold of hyperactivity-impulsivity for adults in the DSM-5.     

Hippocampal sequences link past, present, and future

Disrupting the reactivation of hippocampal neurons during sleep impairs memory consolidation in rats. However, the functional importance of reactivation during awake states is unknown. An experiment in which awake reactivation was disrupted suggests that this phenomenon could adaptively guide behavior by linking previous learning with the current state of the world.