Commentary on “Mediation analysis and categorical variables: The final frontier” by Dawn Iacobucci

The commentary discusses several topics in Dr. Iacobucci's article on mediation analysis with categorical variables including the lack of equivalency of mediated effect measures, ab, and c–c′, that are algebraically equivalent in ordinary least squares regression models. The commentary raises the issue of correlated mediation coefficients and presents formulas to include the correlation in the test of significance. References to new developments in causal mediation analysis for categorical variables are given and the importance of programs of research to establish a mediation theory is emphasized.     

Prior Trauma Exposure for Youth in Treatment Foster Care

Very little research has focused on rates of trauma exposure for youth in treatment foster care (TFC). Available research has utilized record review for assessing exposure, which presents limitations for the range of trauma types examined, as records are predominantly focused on abuse and neglect. The current study examines exposure rates and association with emotional and behavioral outcomes for 229 youth in 46 TFC agencies. The youth in this study had exceptionally high rates of trauma exposure by foster parent report, similar to youth in traditional foster care, with nearly half of the sample exposed to four or more types of traumatic events. A composite child abuse and neglect exposure variable was associated with child and adolescent emotional and behavioral outcomes. Implications for services provided as part of TFC are discussed.     

Attachment Theory and Mindfulness

We initiate a dialog between two central areas in the field of psychology today: attachment theory/research and mindfulness studies. The impact of the early mother-infant relationship on child development has been well established in the literature, with attachment theorists having focused on the correlation between a mother’s capacity for self-regulation and connection (e.g., attunement) with children’s health and developmental outcomes. Because the transition to parenthood is often a stressful one, research has also focused on the importance of the mother’s external and internal support (e.g., self-awareness, recognition of needs) in promoting healthy mother-infant relationships. One promising field in relation to increased internal support is mindfulness, a practice shown to increase emotional regulation while decreasing stress and anxiety. Described as non-judgmental, present-moment awareness, mindfulness has received significant empirical attention over the past three decades and has recently been theorized as an important contributing factor in healthy mother–child relationships. Recognizing the potentially beneficial effects of mindfulness training on healthy attachment, this article reviews relevant literature in presenting a case for exploratory and empirical research into the dynamic relationship between mindfulness, attachment style, maternal health, and children’s development. Grounds for this convergence, as well as suggestions for future research, are presented.     

Parental Divorce, Familial Risk for Depression, and Psychopathology in Offspring: A Three-Generation Study

Research suggests a link between parental divorce and negative child outcomes; however, the presence of parental depression may confound this relationship. Studies exploring the simultaneous effects of depression and parents’ divorce on the adjustment of their children are scarce and rarely have a longitudinal design. This is the first three-generation study of the relative effects of depression and divorce on offspring psychopathology, based on data from a 25-year longitudinal study with families at high and low risk for depression. One hundred seventy-eight grandchildren (mean age?=?13.9?years) of depressed and nondepressed parents and grandparents were evaluated by raters blind to their parents’ and grandparents’ clinical status. We found that in both low and high-risk children, divorce had a limited impact on child adjustment over and above familial risk for depression. Divorce had a significant effect on child outcomes only among high-risk grandchildren with a depressed grandparent and non-depressed parents, with this group showing a threefold risk for anxiety disorders. Results support previous findings suggesting that familial risk for depression largely overshadows the effect of parental divorce on child psychopathology. Possible reasons for the lack of association between divorce and child psychopathology among low-risk offspring are discussed.     

Is academic buoyancy anything more than adaptive coping?

Academic buoyancy refers to a positive, constructive, and adaptive response to the types of challenges and setbacks experienced in a typical and everyday academic setting. In this project we examined whether academic buoyancy explained any additional variance in test anxiety over and above that explained by coping. Two hundred and ninety-eight students in their final two years of compulsory schooling completed self-report measures of academic buoyancy, coping, and test anxiety. Results suggested that buoyancy was inversely related to test anxiety and unrelated to coping. With the exception of test-irrelevant thoughts, test anxiety was positively related to avoidance coping and social support. Test-irrelevant thoughts were inversely related to task focus, unrelated to social support, and positively related to avoidance. A hierarchical regression analysis showed that academic buoyancy explained a significant additional proportion of variance in test anxiety when the variance for coping had already been accounted for. These findings suggest that academic buoyancy can be considered as a distinct construct from that of adaptive coping.     

Can you McGurk yourself? Self-face and self-voice in audiovisual speech

We are constantly exposed to our own face and voice, and we identify our own faces and voices as familiar. However, the influence of self-identity upon self-speech perception is still uncertain. Speech perception is a synthesis of both auditory and visual inputs; although we hear our own voice when we speak, we rarely see the dynamic movements of our own face. If visual speech and identity are processed independently, no processing advantage would obtain in viewing one’s own highly familiar face. In the present experiment, the relative contributions of facial and vocal inputs to speech perception were evaluated with an audiovisual illusion. Our results indicate that auditory self-speech conveys a processing advantage, whereas visual self-speech does not. The data thereby support a model of visual speech as dynamic movement processed separately from speaker recognition.     

The Three Domains of Disgust Scale: factor structure, psychometric properties, and conceptual limitations

This investigation examined the measurement properties of the Three Domains of Disgust Scale (TDDS). Principal components analysis in Study 1 (n = 206) revealed three factors of Pathogen, Sexual, and Moral Disgust that demonstrated excellent reliability, including test-retest over 12 weeks. Confirmatory factor analyses in Study 2 (n = 406) supported the three factors. Supportive evidence for the validity of the Pathogen and Sexual Disgust subscales was found in Study 1 and Study 2 with strong associations with disgust/contamination and weak associations with negative affect. However, the validity of the Moral Disgust subscale was limited. Study 3 (n = 200) showed that the TDDS subscales differentially related to personality traits. Study 4 (n = 47) provided evidence for the validity of the TDDS subscales in relation to multiple indices of disgust/contamination aversion in a select sample. Study 5 (n = 70) further highlighted limitations of the Moral Disgust subscale given the lack of a theoretically consistent association with moral attitudes. Lastly, Study 6 (n = 178) showed that responses on the Moral Disgust scale were more intense when anger was the response option compared with when disgust was the response option. The implications of these findings for the assessment of disgust are discussed.     

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.