Clarifying Heterogeneity of Daytime and Nighttime Symptoms of Posttraumatic Stress in Combat Veterans With Insomnia

Daytime and nighttime symptoms of posttraumatic stress disorder (PTSD) are common among combat veterans and military service members. However, there is a great deal of heterogeneity in how symptoms are expressed. Clarifying the heterogeneity of daytime and nighttime PTSD symptoms through exploratory clustering may generate hypotheses regarding ways to optimally match evidence-based treatments to PTSD symptom profiles. We used mixture modeling to reveal clusters based on 6 daytime and nighttime symptoms of 154 combat veterans with insomnia and varying levels of PTSD symptoms. Three clusters with increasing symptom severity were identified (n1 = 50, n2 = 70, n3 = 34). These results suggest that, among veterans with insomnia, PTSD symptoms tend to exist on a continuum of severity, rather than as a categorical PTSD diagnosis. Hypotheses regarding possible targeted treatment strategies for veterans within each identified cluster, as well as ways to generalize these methods to other groups within the military, are discussed.     

Validating age-related functional imaging changes in verbal working memory with acute stroke

Functional imaging studies consistently find that older adults recruit bilateral brain regions in cognitive tasks that are strongly lateralized in younger adults, a characterization known as the Hemispheric Asymmetry Reduction in Older Adults model. While functional imaging displays what brain areas are active during tasks, it cannot demonstrate what brain regions are necessary for task performance. We used behavioral data from acute stroke patients to test the hypothesis that older adults need both hemispheres for a verbal working memory task that is predominantly left-lateralized in younger adults. Right-handed younger (age ? 50, n = 7) and older adults (age > 50, n =21) with acute unilateral stroke, as well as younger (n =6) and older (n =13) transient ischemic attack (TIA) patients, performed a self-paced verbal item-recognition task. Older patients with stroke to either hemisphere had a higher frequency of deficits in the verbal working memory task compared to older TIA patients. Additionally, the deficits in older stroke patients were mainly in retrieval time while the deficits in younger stroke patients were mainly in accuracy. These data suggest that bihemispheric activity is necessary for older adults to successfully perform a verbal working memory task.     

Assessing the double phonemic representation in bilingual speakers of Spanish and English: an electrophysiological study

Event Related Potentials (ERPs) were recorded from Spanish-English bilinguals (N = 10) to test pre-attentive speech discrimination in two language contexts. ERPs were recorded while participants silently read magazines in English or Spanish. Two speech contrast conditions were recorded in each language context. In the phonemic in English condition, the speech sounds represented two different phonemic categories in English, but represented the same phonemic category in Spanish. In the phonemic in Spanish condition, the speech sounds represented two different phonemic categories in Spanish, but represented the same phonemic categories in English. Results showed pre-attentive discrimination when the acoustics/phonetics of the speech sounds match the language context (e.g., phonemic in English condition during the English language context). The results suggest that language contexts can affect pre-attentive auditory change detection. Specifically, bilinguals’ mental processing of stop consonants relies on contextual linguistic information.     

Depressive symptoms, cortisol, and cognition during human aging: the role of negative aging perceptions

Depressive symptoms and memory impairments are associated with heightened stress hormone levels during aging. A factor that is related to memory deficits during aging is internalized negative aging stereotypes; the idea people have about the process of aging. In this study, we assessed the associations between internalized negative aging stereotypes, depressive symptoms, subjective and objective memory assessments, and cortisol concentration among older adults. Forty older adults aged between 58 and 85 years (18 females and 22 males; mean age?±?SD: 71.25?±?8.80 years) were assessed in this study. Measures of internalized negative aging stereotypes, depressive symptoms, and both subjective and objective memory performance were assessed. Salivary samples were obtained for measurement of cortisol concentration. Stepwise linear regressions were executed in our main analyses. Internalized negative aging stereotypes were associated with increased depressive symptoms and subjective memory complaints. No significant differences were observed for objective memory performance, or cortisol concentration. Internalized negative aging stereotypes are associated with increased depressive symptomatology and subjective complaints of memory; however, they do not predict increased cortisol concentration nor objective memory performance during aging. These results indicate that the mechanism underlying the association between internalized negative aging stereotypes and cognitive impairments may not be related to dysregulations of cortisol secretion among older adults.     

Look who's talking: speech style and social context in language input to infants are linked to concurrent and future speech development

Language input is necessary for language learning, yet little is known about whether, in natural environments, the speech style and social context of language input to children impacts language development. In the present study we investigated the relationship between language input and language development, examining both the style of parental speech, comparing ‘parentese’ speech to standard speech, and the social context in which speech is directed to children, comparing one‐on‐one (1:1) to group social interactions. Importantly, the language input variables were assessed at home using digital first‐person perspective recordings of the infants' auditory environment as they went about their daily lives (N =26, 11‐ and 14‐months‐old). We measured language development using (a) concurrent speech utterances, and (b) word production at 24 months. Parentese speech in 1:1 contexts is positively correlated with both concurrent speech and later word production. Mediation analyses further show that the effect of parentese speech‐1:1 on infants' later language is mediated by concurrent speech. Our results suggest that both the social context and the style of speech in language addressed to children are strongly linked to a child's future language development.     

Nanoindentation study of size effects in nickel–graphene nanocomposites

Metal–graphene nanocomposites find applications in nanoscale devices, as functional materials and can serve as a test bed to gain insight into fundamental deformation mechanisms of metals under geometric confinement. Here, we report full atomistic nanoindentation simulations for nickel–graphene nanocomposites with varied numbers of layers of graphene sheets to investigate the size effects on the hardness, and to understand how emerging dislocation loops interact with the nickel–graphene interface under varied geometric confinements. A detailed analysis of the plastic deformation mechanism shows that as dislocation loops reach the nickel–graphene interface, the local bending of the graphene sheet is altered and further dislocation propagation is blocked. An increase in the number of graphene layers decreases the hardness, but increases the maximum elastic deformation of the nickel–graphene nanocomposites. These findings indicate that the mechanical properties of nickel–graphene nanocomposites can be engineered by controlling the thickness of nickel and graphene layers, respectively.     

Perpetrator and victim perceptions of perpetrator's masculinity as a risk factor for violence: A meta-ethnography synthesis

Men are over-represented as both perpetrators and victims of violence. The purpose of this systematic review was to examine the relationship between masculinity and violence from the perspectives of the perpetrators and victims. In order to provide the best available scientific evidence, four databases were searched and a Critical Appraisal Skills Programme tool was used to evaluate 10 studies. A meta-ethnography approach was also employed to synthesize the selected studies. The analysis revealed a number of reciprocal themes that act as risk factors for violence. This included a masculinization process, available resources, ethnic minority identification and alcohol and substance abuse. This review highlights the need for further research exploring different reciprocal themes and their association with masculinity and violence. Further research in this field could help clinicians improve their practice by helping clinicians widen their discussions about the violence committed by some males. Additional investigations could also improve offender treatment programs, which, in turn, could assist offenders by helping them challenge schemas and cognitive distortions that may precipitate their violence.     

Mental Health Issues of Breast Cancer Patients: The Kerala Context

The present study was a qualitative enquiry into the mental health issues of breast cancer patients in Kerala. The sample consisted of thirty mastectomy inpatients in the age range 20–60 years, undergoing chemotherapy/radiation therapy for the past 6 months to 1 year. The interview data were thematically analysed, and the major emergent themes elicited were psychopharmacological and socio-economic in nature. Treatment-related issues included dizziness and fatigue, whereas fear of death, fear of recurrence, discrimination, inability to take care of their children, and the escalating cost of treatment were the main psychological concerns.