Content Analysis of Suicide Notes as a Test of the Motivational Component of the Existential‐Constructivist Model of Suicide

A sample of 40 suicide notes were analyzed for motivational content in relation to an existential‐constructivist theory of suicide. Results generally supported the 4 theoretical categories of somatic, relational, spiritual, and psychological motivations, with 39 notes having content that could be classified according to the aforementioned categories. Psychological motivations were found to be the most prevalent, followed by relational, spiritual, and somatic concerns. Notes of completed suicides included more relational motivations than did those of suicide attempters, and older writers of notes showed more psychological and fewer spiritual motivations than did younger writers. Recommendations are offered for revising the theory to provide a stronger meaning‐based understanding of suicidal behavior.     

Individual differences in executive function partially explain the socioeconomic gradient in middle‐school academic achievement

Children from families with low socioeconomic status (SES) earn lower grades, perform worse on achievement tests, and attain less education on average than their peers from higher‐SES families. We evaluated neurocognitive mediators of SES disparities in achievement in a diverse sample of youth whose data were linked to administrative records of performance on school‐administered tests of 7th grade reading and math proficiency (N = 203). We used structural equation modeling to evaluate whether associations between SES (measured at ages 8–9) and achievement (measured at age 13) are mediated by verbal ability and executive function (measured at age 10), a suite of top‐down mental processes that facilitate control of thinking and behavior. Children from relatively higher‐SES families performed better than their lower‐SES peers on all neurocognitive and achievement measures, and SES disparities in both reading and math achievement were partially mediated by variation in executive function, but not verbal ability. SES disparities in executive function explained approximately 37% of the SES gap in math achievement and 17% of the SES gap in reading achievement. Exploratory modeling suggests that SES‐related variation in working memory may play a particularly prominent role in mediation. We discuss potential implications of these findings for research, intervention programming, and classroom practice.     

Impact of perceived value on casual mobile game loyalty: The moderating effect of intensity of playing

The retention rate of mobile game players is one of the subjects that spark most interest in the industry, as many abandon the games only a few hours after downloading them. This study examines the antecedents of loyalty towards mobile games from the perspective of perceived value and explores the moderating effect of intensity of playing. The results revealed that hedonic value (i.e., perceived enjoyment and perceived attractiveness) and, to a lesser extent, utilitarian value (i.e., effort expectancy and perceived usefulness) are crucial in the loyalty that players feel towards mobile games. Intensity of playing weakens the relationship between perceived usefulness, perceived enjoyment and loyalty intention. Based on the findings, theoretical and practical implications are provided.     

Extinction circuits for fear and addiction overlap in prefrontal cortex

Extinction is a form of inhibitory learning that suppresses a previously conditioned response. Both fear and drug seeking are conditioned responses that can lead to maladaptive behavior when expressed inappropriately, manifesting as anxiety disorders and addiction, respectively. Recent evidence indicates that the medial prefrontal cortex (mPFC) is critical for the extinction of both fear and drug-seeking behaviors. Moreover, a dorsal-ventral distinction is apparent within the mPFC, such that the prelimbic (PL-mPFC) cortex drives the expression of fear and drug seeking, whereas the infralimbic (IL-mPFC) cortex suppresses these behaviors after extinction. For conditioned fear, the dorsal-ventral dichotomy is accomplished via divergent projections to different subregions of the amygdala, whereas for drug seeking, it is accomplished via divergent projections to the subregions of the nucleus accumbens. Given that the mPFC represents a common node in the extinction circuit for these behaviors, treatments that target this region may help alleviate symptoms of both anxiety and addictive disorders by enhancing extinction memory.Emotional memories, both in the aversive and appetitive domains, are important for guiding behavior. Regulating the expression of these memories is critical for mental health. Extinction of classical conditioning is one form of emotion regulation that is easily modeled in animals. In the aversive domain, a conditioned stimulus (CS) is typically paired with a shock, while in the appetitive domain, a CS is paired with the availability of food or drug reward. Repeated presentation of the CS in the absence of the reinforcer leads to extinction of conditioned fear or drug-seeking behaviors. In recent years, there have been great advances in our understanding of the neural circuitry responsible for this form of inhibitory learning (for reviews, see Cammarota et al. 2005; Maren 2005; Myers and Davis 2007; Quirk and Mueller 2008). The prefrontal cortex has been strongly implicated in fear expression (Powell et al. 2001; Vidal-Gonzalez et al. 2006; Corcoran and Quirk 2007) and fear extinction (Herry and Garcia 2002; Milad and Quirk 2002; Gonzalez-Lima and Bruchey 2004; Hugues et al. 2004; Burgos-Robles et al. 2007; Hikind and Maroun 2008; Lin et al. 2008; Mueller et al. 2008; Sotres-Bayon et al. 2008), and more recently, in expression of drug seeking after extinction (Peters et al. 2008a,b). These findings are consistent with a well-documented role of the prefrontal cortex in executive function and emotional regulation (Miller 2000; Fuster 2002; Quirk and Beer 2006; Sotres-Bayon et al. 2006).In this review, we propose that the medial prefrontal cortex (mPFC) regulates the expression of both fear and drug memories after extinction, through divergent projections to the amygdala and nucleus accumbens, respectively. Extinction failure in the aversive domain can lead to anxiety disorders (Delgado et al. 2006; Milad et al. 2006), while extinction failure in the appetitive domain can lead to relapse in addicted subjects (Kalivas et al. 2005; Garavan and Hester 2007). A common neural circuit for extinction of fear and drug memories would suggest shared mechanisms and treatment strategies across both domains.     

Are dietary restraint scales valid measures of moderate- to long-term dietary restriction? Objective biological and behavioral data suggest not

Prospective studies indicate that elevated scores on dietary restraint scales predict bulimic symptom onset, but experiments indicate that assignment to dietary restriction interventions reduces bulimic symptoms. One possible explanation for the inconsistent findings is that the dietary restraint scales used in the former studies are not valid measures of dietary restriction. The authors previously found that dietary restraint scales were not inversely correlated with objective measures of short-term caloric intake (E. Stice, M. Fisher, & M. R. Lowe, 2004). In this follow-up report, 3 studies indicated that the Three-Factor Eating Questionnaire dietary restraint scale was not correlated with doubly labeled water estimated energy intake over 2-week periods or with observationally measured caloric intake over 3 months. Results from this study and others suggest that dietary restraint scales may not be valid measures of moderate- to long-term dietary restriction and imply the need to reinterpret findings from studies that have used dietary restraint scales.     

Support for hybrid models of the age of acquisition of English nouns

Age of acquisition (AoA) is a psycholinguistic construct that refers to the chronological age at which a given word is acquired. Contemporary theories of AoA have focused on lexical acquisition with respect to either the developing phonological or semantic systems. One way of testing the relative dominance of phonological or semantic contributions is through open-source psycholinguistic databases, whereby AoA may be correlated with other variables (e.g., morphology, semantics, phonology). We report two multiple regression analyses conducted on a corpus of English nouns with, respectively, subjective and objective AoA measures as the dependent variables and a combination of 10 predictors, including 2 semantic, 4 phonological, 2 morphological, and 2 lexical. This multivariate combination of predictors accounted for significant proportions of the variance of AoA in both analyses. We argue that this evidence supports hybrid models of language development that integrate multiple levels of processing—from sound to meaning.     

Efficacy of a program to encourage walking in VA elderly primary care patients: the role of pain

Pain may be a barrier or a negative outcome of initiating and maintaining an exercise program in elderly patients. The purpose of this study was to examine the role of pain in a program designed to increase walking for exercise in 181 veteran primary care patients (60 - 80 years). Self-reported physical activity (min-walked per week) and pain were assessed at baseline, 6, and 12 months. Walking for exercise increased over time without significant changes in pain. Analyses suggested that baseline pain was not a barrier to initiating or maintaining a walking exercise program, nor did increased walking influence reports of pain. These results suggest that patients can be encouraged to engage in physical activity, even if they are currently suffering from pain.