Publications by authors named "Ben Richardson"

64 Publications

Independent of differences in taste, B6N mice consume less alcohol than genetically similar B6J mice, and exhibit opposite polarity modulation of tonic GABAR currents by alcohol.

Neuropharmacology 2022 Mar 20;206:108934. Epub 2021 Dec 20.

Department of Integrative Physiology and Neuroscience, 1815 Ferdinands Lane, Washington State University, Pullman, WA, 99164-7620, USA. Electronic address:

Genetic differences in cerebellar sensitivity to alcohol (EtOH) influence EtOH consumption phenotype in animal models and contribute to risk for developing an alcohol use disorder in humans. We previously determined that EtOH enhances cerebellar granule cell (GC) tonic GABAR currents in low EtOH consuming rodent genotypes, but suppresses it in high EtOH consuming rodent genotypes. Moreover, pharmacologically counteracting EtOH suppression of GC tonic GABAR currents reduces EtOH consumption in high alcohol consuming C57BL/6J (B6J) mice, suggesting a causative role. In the low EtOH consuming rodent models tested to date, EtOH enhancement of GC tonic GABAR currents is mediated by inhibition of neuronal nitric oxide synthase (nNOS) which drives increased vesicular GABA release onto GCs and a consequent enhancement of tonic GABAR currents. Consequently, genetic variation in nNOS expression across rodent genotypes is a key determinant of whether EtOH enhances or suppresses tonic GABAR currents, and thus EtOH consumption. We used behavioral, electrophysiological, and immunocytochemical techniques to further explore the relationship between EtOH consumption and GC GABAR current responses in C57BL/6N (B6N) mice. B6N mice consume significantly less EtOH and achieve significantly lower blood EtOH concentrations than B6J mice, an outcome not mediated by differences in taste. In voltage-clamped GCs, EtOH enhanced the GC tonic current in B6N mice but suppressed it in B6J mice. Immunohistochemical and electrophysiological studies revealed significantly higher nNOS expression and function in the GC layer of B6N mice compared to B6Js. Collectively, our data demonstrate that despite being genetically similar, B6N mice consume significantly less EtOH than B6J mice, a behavioral difference paralleled by increased cerebellar nNOS expression and opposite EtOH action on GC tonic GABAR currents in each genotype.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.neuropharm.2021.108934DOI Listing
March 2022

AusTraits, a curated plant trait database for the Australian flora.

Sci Data 2021 09 30;8(1):254. Epub 2021 Sep 30.

James Cook University, Douglas, Australia.

We introduce the AusTraits database - a compilation of values of plant traits for taxa in the Australian flora (hereafter AusTraits). AusTraits synthesises data on 448 traits across 28,640 taxa from field campaigns, published literature, taxonomic monographs, and individual taxon descriptions. Traits vary in scope from physiological measures of performance (e.g. photosynthetic gas exchange, water-use efficiency) to morphological attributes (e.g. leaf area, seed mass, plant height) which link to aspects of ecological variation. AusTraits contains curated and harmonised individual- and species-level measurements coupled to, where available, contextual information on site properties and experimental conditions. This article provides information on version 3.0.2 of AusTraits which contains data for 997,808 trait-by-taxon combinations. We envision AusTraits as an ongoing collaborative initiative for easily archiving and sharing trait data, which also provides a template for other national or regional initiatives globally to fill persistent gaps in trait knowledge.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/s41597-021-01006-6DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8484355PMC
September 2021

Homologous organization of cerebellar pathways to sensory, motor, and associative forebrain.

Cell Rep 2021 09;36(12):109721

Neuroscience Institute, Washington Road, Princeton University, Princeton, NJ 08544, USA. Electronic address:

Cerebellar outputs take polysynaptic routes to reach the rest of the brain, impeding conventional tracing. Here, we quantify pathways between the cerebellum and forebrain by using transsynaptic tracing viruses and a whole-brain analysis pipeline. With retrograde tracing, we find that most descending paths originate from the somatomotor cortex. Anterograde tracing of ascending paths encompasses most thalamic nuclei, especially ventral posteromedial, lateral posterior, mediodorsal, and reticular nuclei. In the neocortex, sensorimotor regions contain the most labeled neurons, but we find higher densities in associative areas, including orbital, anterior cingulate, prelimbic, and infralimbic cortex. Patterns of ascending expression correlate with c-Fos expression after optogenetic inhibition of Purkinje cells. Our results reveal homologous networks linking single areas of the cerebellar cortex to diverse forebrain targets. We conclude that shared areas of the cerebellum are positioned to provide sensory-motor information to regions implicated in both movement and nonmotor function.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.celrep.2021.109721DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8506234PMC
September 2021

Exploring the features of an app-based just-in-time intervention for depression.

J Affect Disord 2021 08 24;291:279-287. Epub 2021 May 24.

School of Psychology, Deakin University, Australia. Electronic address:

Background: Technological advancements make it possible to deliver depression interventions via smartphone applications ("Apps"), including those that deliver content "just-in-time" (e.g., in response to acute negative mood states). This study examined whether an app-based just-in-time intervention (ImproveYourMood+) decreased depressive symptoms, and whether the following features were related to symptom improvement: micro-intervention content, mood monitoring, and just-in-time prompts to use content.

Methods: Participants (n = 235) from the general population who self-identified as wanting to improve their negative mood were randomised to a waitlist control group (n = 55) or one of three intervention groups: MoodTracker (monitoring-only, n = 58), ImproveYourMood (monitoring and content; n = 62), or ImproveYourMood+ (monitoring, content, and prompts; n = 60). The active intervention phase was 3 weeks. Depressive and anxiety symptoms, and negative automatic thoughts were assessed at baseline, immediately post-intervention, and one month following post-intervention.

Results: Linear mixed modelling revealed greater declines over time in depressive and anxiety symptoms and negative automatic thoughts for the ImproveYourMood group (standardized mean differences [SMDs] ranged from .32 to .40) and improves for the ImproveYourMood+ group for negative automatic thoughts (SMDs ≥ .37) compared to the waitlist control group. No between-group differences were observed between the MoodTracker and control groups (SMDs = .04-.23). User experience appeared to be superior in more comprehensive/multi-modal versions.

Limitations: The study employed a naturalistic design, whereby participants self-selected to utilise the program, did not complete eligibility assessments, and did not receive compensation. The study therefore attained considerable drop-out rate (~50% by the follow-up timepoints), potentially reflecting the usage patterns of real-world mental health apps.

Conclusions: The findings suggest that micro-interventions can be an effective way to reduce depressive symptoms both in the moment and 1-2 months later. Integration of micro-interventions with full treatment programs is a viable next step in micro-intervention research.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.jad.2021.05.021DOI Listing
August 2021

CB1 Receptor Signaling Modulates Amygdalar Plasticity during Context-Cocaine Memory Reconsolidation to Promote Subsequent Cocaine Seeking.

J Neurosci 2021 01 30;41(4):613-629. Epub 2020 Nov 30.

Department of Integrative Physiology and Neuroscience, Washington State University College of Veterinary Medicine, Pullman, Washington 99164

Contextual drug-associated memories precipitate craving and relapse in cocaine users. Such associative memories can be weakened through interference with memory reconsolidation, a process by which memories are maintained following memory retrieval-induced destabilization. We hypothesized that cocaine-memory reconsolidation requires cannabinoid type 1 receptor (CB1R) signaling based on the fundamental role of the endocannabinoid system in synaptic plasticity and emotional memory processing. Using an instrumental model of cocaine relapse, we evaluated whether systemic CB1R antagonism (AM251; 3 mg/kg, i.p.) during memory reconsolidation altered (1) subsequent drug context-induced cocaine-seeking behavior as well as (2) cellular adaptations and (3) excitatory synaptic physiology in the basolateral amygdala (BLA) in male Sprague Dawley rats. Systemic CB1R antagonism, during, but not after, cocaine-memory reconsolidation reduced drug context-induced cocaine-seeking behavior 3 d, but not three weeks, later. CB1R antagonism also inhibited memory retrieval-associated increases in BLA zinc finger 268 (zif268) and activity regulated cytoskeletal-associated protein (Arc) immediate-early gene (IEG) expression and changes in BLA AMPA receptor (AMPAR) and NMDA receptor (NMDAR) subunit phosphorylation that likely contribute to increased receptor membrane trafficking and synaptic plasticity during memory reconsolidation. Furthermore, CB1R antagonism increased memory reconsolidation-associated spontaneous EPSC (sEPSC) frequency in BLA principal neurons during memory reconsolidation. Together, these findings suggest that CB1R signaling modulates cellular and synaptic mechanisms in the BLA that may facilitate cocaine-memory strength by enhancing reconsolidation or synaptic reentry reinforcement, or by inhibiting extinction-memory consolidation. These findings identify the CB1R as a potential therapeutic target for relapse prevention. Drug relapse can be triggered by the retrieval of context-drug memories on re-exposure to a drug-associated environment. Context-drug associative memories become destabilized on retrieval and must be reconsolidated into long-term memory stores to persist. Hence, targeted interference with memory reconsolidation can weaken maladaptive context-drug memories and reduce the propensity for drug relapse. Our findings indicate that cannabinoid type 1 receptor (CB1R) signaling is critical for context-cocaine memory reconsolidation and subsequent drug context-induced reinstatement of cocaine-seeking behavior. Furthermore, cocaine-memory reconsolidation is associated with CB1R-dependent immediate-early gene (IEG) expression and changes in excitatory synaptic proteins and physiology in the basolateral amygdala (BLA). Together, our findings provide initial support for CB1R as a potential therapeutic target for relapse prevention.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1523/JNEUROSCI.1390-20.2020DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7842758PMC
January 2021

The effects of fitspiration images on body attributes, mood and eating behaviors: An experimental Ecological Momentary Assessment study in females.

Body Image 2020 Dec 6;35:279-287. Epub 2020 Nov 6.

Melbourne School of Psychological Sciences, The University of Melbourne, Redmond Barry Building, Melbourne, VIC, 3010, Australia; Evolution and Ecology Research Centre, School of Biological, Earth and Environment Sciences, UNSW Sydney, Sydney, NSW, 2052, Australia. Electronic address:

Through an experimental Ecological Momentary Assessment (EMA) design, we assessed the effects of fitspiration images (relative to neutral) on body image, mood and disordered eating and whether trait body dissatisfaction, thin-ideal internalization and pressures from the media, family and peers moderated these effects. After completing trait-based measures, 85 women were prompted via a mobile application 6 times daily for 7 days to view an image (fitspiration or neutral) and report on state levels of perceived pressures to attain an idealized physique, satisfaction with various body attributes, mood and eating behavior. When participants were exposed to fitspiration images, their perceived pressure to attain an idealized physique was significantly higher than after exposure to the control images. This effect was most pronounced for women experiencing pressure from the media. Furthermore, fitspiration images lowered the extent to which women felt that idealized physiques were attainable, and decreased satisfaction with current fitness. There were no significant effects on mood and disordered eating. Exposure to fitspiration content predicted only a few adverse outcomes in terms of negative body attributes and perceived pressures to attain a similar physique, suggesting that its content is not as detrimental as initially believed, but further research is needed.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.bodyim.2020.09.011DOI Listing
December 2020

Redefining fatty liver disease: an international patient perspective.

Lancet Gastroenterol Hepatol 2021 01 5;6(1):73-79. Epub 2020 Oct 5.

Storr Liver Centre, Westmead Institute for Medical Research, Westmead Hospital and University of Sydney, Westmead, NSW, Australia. Electronic address:

Despite its increased recognition as a major health threat, fatty liver disease associated with metabolic dysfunction remains largely underdiagnosed and undertreated. An international consensus panel has called for the disease to be renamed from non-alcoholic fatty liver disease (NAFLD) to metabolic-associated fatty liver disease (MAFLD) and has suggested how the disease should be diagnosed. This Viewpoint explores the call from the perspective of patient advocacy groups. Patients are well aware of the negative consequences of the NAFLD acronym. This advocacy group enthusiastically endorses the call to reframe the disease, which we believe will ultimately have a positive effect on patient care and quality of life and, through this effect, will reduce the burden on health-care systems. For patients, policy makers, health planners, donors, and non-hepatologists, the new acronym MAFLD is clear, squarely placing the disease as a manifestation of metabolic dysfunction and improving understanding at a public health and patient level. The authors from representative patient groups are supportive of this change, particularly as the new acronym is meaningful to all citizens as well as governments and policy makers, and, above all, is devoid of any stigma.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/S2468-1253(20)30294-6DOI Listing
January 2021

The differential impact of viewing fitspiration and thinspiration images on men's body image concerns: An experimental ecological momentary assessment study.

Body Image 2020 Dec 22;35:96-107. Epub 2020 Sep 22.

Melbourne School of Psychological Sciences, The University of Melbourne, Redmond Barry Building, Melbourne, VIC, 3010, Australia. Electronic address:

To date, little is known about the impact of fitspiration and thinspiration exposure on men, as previous studies on these social media trends were primarily conducted on women. Male participants (n = 223) completed baseline measures of trait body image, then used a smartphone application to complete up to six state-based assessments daily for seven days. In each assessment, participants were randomly assigned to one of three image conditions (fitspiration, thinspiration, or neutral). Before and after viewing each image, they reported state body fat dissatisfaction, muscularity dissatisfaction, negative mood, and urge to engage in behaviours to reduce body fat and increase muscularity. Multi-level analyses revealed that compared to viewing neutral images, viewing fitspiration images increased men's body dissatisfaction, whereas viewing thinspiration images decreased body dissatisfaction. Viewing either fit- or thinspiration images also led to lower mood and greater urges to increase muscularity, whereas only fitspiration images increased urges to reduce body fat. Men with greater baseline muscularity dissatisfaction and higher appearance comparison were most vulnerable to muscularity dissatisfaction after viewing fitspiration images. Findings suggest the importance of limiting exposure to fitspiration imagery and implementing social media literacy programmes for men and well as women.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.bodyim.2020.08.008DOI Listing
December 2020

Efficacy of a Smartphone App Intervention for Reducing Caregiver Stress: Randomized Controlled Trial.

JMIR Ment Health 2020 Jul 24;7(7):e17541. Epub 2020 Jul 24.

Deakin University, Geelong, Australia.

Background: Caregivers play a pivotal role in maintaining an economically viable health care system, yet they are characterized by low levels of psychological well-being and consistently report unmet needs for psychological support. Mobile app-based (mobile health [mHealth]) interventions present a novel approach to both reducing stress and improving well-being.

Objective: This study aims to evaluate the effectiveness of a self-guided mobile app-based psychological intervention for people providing care to family or friends with a physical or mental disability.

Methods: In a randomized, single-blind, controlled trial, 183 caregivers recruited through the web were randomly allocated to either an intervention (n=73) or active control (n=110) condition. The intervention app contained treatment modules combining daily self-monitoring with third-wave (mindfulness-based) cognitive-behavioral therapies, whereas the active control app contained only self-monitoring features. Both programs were completed over a 5-week period. It was hypothesized that intervention app exposure would be associated with decreases in depression, anxiety, and stress, and increases in well-being, self-esteem, optimism, primary and secondary control, and social support. Outcomes were assessed at baseline, postintervention, and 3-4 months postintervention. App quality was also assessed.

Results: In total, 25% (18/73) of the intervention participants were lost to follow-up at 3 months, and 30.9% (34/110) of the participants from the wait-list control group dropped out before the postintervention survey. The intervention group experienced reductions in stress (b=-2.07; P=.04) and depressive symptoms (b=-1.36; P=.05) from baseline to postintervention. These changes were further enhanced from postintervention to follow-up, with the intervention group continuing to report lower levels of depression (b=-1.82; P=.03) and higher levels of emotional well-being (b=6.13; P<.001), optimism (b=0.78; P=.007), self-esteem (b=-0.84; P=.005), support from family (b=2.15; P=.001), support from significant others (b=2.66; P<.001), and subjective well-being (b=4.82; P<.001). On average, participants completed 2.5 (SD 1.05) out of 5 treatment modules. The overall quality of the app was also rated highly, with a mean score of 3.94 out of a maximum score of 5 (SD 0.58).

Conclusions: This study demonstrates that mHealth psychological interventions are an effective treatment option for caregivers experiencing high levels of stress. Recommendations for improving mHealth interventions for caregivers include offering flexibility and customization in the treatment design.

Trial Registration: Australian New Zealand Clinical Trial Registry ACTRN12616000996460; https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=371170.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.2196/17541DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7414413PMC
July 2020

Are Fitbits implicated in body image concerns and disordered eating in women?

Health Psychol 2020 Oct 14;39(10):900-904. Epub 2020 May 14.

School of Psychological Sciences.

Objective: Using a daily monitoring framework, we examined the psychological consequences of Fitbit self-tracking on state body satisfaction, disordered eating (DE; i.e., binge eating and dietary restraint), levels of exercise engagement, and motivations (appearance vs. fitness/health) in adult women. A further aim within the Fitbit group was to assess whether the level of steps achieved on 1 day would be associated with the state-based outcome measures on the subsequent day.

Method: In total, 262 participants who had never used a wearable fitness self-tracking device were allocated to a Fitbit ( = 101) or control condition ( = 161). Participants provided baseline data on sociodemographics, eating pathology, and exercise and then completed a 10-day Ecological Momentary Assessment (EMA) protocol assessing exercise amount and motives, body satisfaction, and DE symptoms via a mobile application. Those in the Fitbit condition wore a Fitbit over the entire assessment period.

Results: The use of a Fitbit over a 10-day period had no significant effects on exercise behavior or body satisfaction compared to a control group. However, those in the Fitbit group were more likely to exercise to reach fitness goals and less likely to engage in dietary restraint and binge-eating behavior. Among participants in the Fitbit condition, steps achieved the previous day were not predictive of exercise engagement, body satisfaction, or DE symptoms on the subsequent day.

Conclusions: Our study failed to link fitness self-tracking to body dissatisfaction and DE, at least in the early stages of use. Future research directions regarding alternative pathways through which self-tracking devices may exert negative influences are discussed. (PsycInfo Database Record (c) 2020 APA, all rights reserved).
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1037/hea0000881DOI Listing
October 2020

A network analysis comparison of central determinants of body dissatisfaction among pregnant and non-pregnant women.

Body Image 2020 Mar 25;32:111-120. Epub 2019 Dec 25.

Monash Centre for Health Research and Implementation, Monash University, Australia.

The objective of the present study was to compare body dissatisfaction of pregnant (n = 1245 overall; n = 320 trimester 1, n = 497 trimester 2, n = 428 trimester 3) and non-pregnant (n = 547) women in terms of: (a) global dissatisfaction, (b) dissatisfaction with specific body parts/features, and (c) strength of inter-relation among these areas of dissatisfaction. While ANOVAs revealed small group differences in overall body dissatisfaction ratings for appearance and function, more sizable differences were observed at the item level. Network analysis showed that the dissatisfaction items clustered together in similar ways across groups, but that the relative importance of these items for the networks differed by group. In particular, dissatisfaction with chest was much less connected to other areas of dissatisfaction for pregnant women, whilst dissatisfaction with shape and/or weight were more strongly connected to other items for this group. Body function items were less important in the network for non-pregnant women. Findings support earlier qualitative findings suggesting that pregnant women are concerned with both appearance and functioning of their bodies. More broadly, information gleaned at the item level highlights the value in exploring areas of dissatisfaction that may increase understanding of global dissatisfaction ratings.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.bodyim.2019.12.001DOI Listing
March 2020

Ecological momentary assessment of drinking in young adults: An investigation into social context, affect and motives.

Addict Behav 2019 11 7;98:106019. Epub 2019 Jun 7.

School of Psychology, Deakin University, Geelong, Australia; Centre for Drug Use, Addictive and Anti-social Behaviours Research (CEDAAR), Deakin University, Australia. Electronic address:

Introduction: Daily assessment studies have examined how day specific factors, such as affect, social context, and drinking motives, alongside dispositional drinking motives, predict young adults' drinking. However, these studies did not examine how the interplay between drinking motives (dispositional and day specific) and multiple features of the drinking situation predict drinking with respect to either the initial decision to drink or the quantity of alcohol consumed. Ecological momentary assessment (EMA) via smartphone technology, enables us to address this gap by evaluating to what extent dispositional drinking motives and day specific factors are associated with: a) the initiation of drinking episodes and; b) the quantity of alcohol consumed.

Methods: Participants were 83 young adults (63 female) aged 18 to 30 (M = 21.42, SD = 3.09) who resided in Australia and participated in an EMA study for 21 days via their smartphone. On a daily basis, participants received three random-interval prompts that measured momentary affect, drinking motives, social context (e.g., people present in the social context and if these individuals are drinking), and alcohol use.

Results: A multilevel hurdle analysis found that young adults were more likely to both initiate a drinking episode and consume a higher quantity of alcohol if they were surrounded by other people who were drinking and were motivated to drink to conform to the reference group.

Conclusions: This study is the first of its kind to demonstrate that different drinking behaviors (i.e., initiation and quantity of alcohol consumed) are associated with a similar set of predictors. Drinking-based interventions that address these risk factors could effectively reduce risky drinking as it would intervene on both the decision to initiate alcohol use, and the decision to continue drinking.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.addbeh.2019.06.008DOI Listing
November 2019

Delivering Personalized Protective Behavioral Drinking Strategies via a Smartphone Intervention: a Pilot Study.

Int J Behav Med 2019 Aug;26(4):401-414

Faculty of Health, School of Psychology, Deakin University, 221 Burwood Highway, Burwood, Victoria, 3125, Australia.

Background: Smartphone-based interventions are a potentially effective way to minimize alcohol-related harm in young adult, non-dependent drinkers. This pilot study is the first to evaluate the benefits and feasibility of a personalized alcohol harm-minimization intervention delivered via smartphones.

Methods: Within a single-blind, randomized controlled design, 45 young adults were randomly assigned to either the intervention app (n = 25; 18 females; M = 21.36 years, SD = 4.15 years) or the control app (n = 20; 18 females; M = 22.75; SD = 4.41). The two primary outcomes were frequency of risky drinking and drinking-related harms, and the secondary outcome was frequency of protective behavioral strategies (PBS) use. All outcomes were measured at baseline and immediately post-intervention. Using the Enlight framework [1], usability was evaluated via structured one-on-one phone interviews with a subgroup of six participants from the intervention group (3 females; M = 19.5 years, SD = 1.64).

Results: There was no significant reduction in the primary outcomes from baseline to post-intervention across the groups. For the secondary outcome, the application of PBS within drinking contexts increased at follow-up for those in the intervention group but not for control participants. End-users rated the app as highly usable but had some concerns with repetition of the app-recommended strategies.

Conclusions: This intervention, designed to reduce risky drinking behaviors among young adults, was rated as highly usable and was shown to increase the application of harm minimization strategies within drinking contexts. While the intervention and its delivery show promise, it did not appear to mitigate risky drinking behaviors. Implications of this research and future directions are discussed.

Trial Registration: This trial is registered at the Australian New Zealand Clinical Trials Registry: BLINDED.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s12529-019-09789-0DOI Listing
August 2019

Co-development of "BRAIN-TRK": Qualitative examination of acceptability, usability and feasibility of an App to support nurses' care for patients with behavioural and psychological symptoms of neurocognitive disorders in hospital.

J Clin Nurs 2019 Aug 21;28(15-16):2868-2879. Epub 2019 Apr 21.

School of Nursing and Midwifery, Deakin University, Geelong, Victoria, Australia.

Aims And Objectives: (a) Describe the co-development of a point-of-care App to promote uptake of best practice recommendations and consolidate nurses' knowledge for managing symptoms of neurocognitive disorders. (b) Report acceptability, usability and feasibility of the App to nurses for patient care in hospital.

Background: Strategies used in hospitals to reduce symptoms, risk of harm, or complications of behavioural and psychological symptoms associated with neurocognitive disorders are frequently inconsistent with best practice recommendations.

Design: Three-stage, mixed-methods, process and outcome evaluation.

Methods: The App was co-developed with experts, nurse end-users and a consumer. Evaluation data were collected from a convenience sample of nurses observed during delivery of 80.5 hr of care to 38 patients; the App (n = 32 patients); and individual and focus group interviews with nurses (n = 25). Reporting adhered to an adapted STROBE checklist.

Results: The App included three components: cognition and risk assessment; tailored evidence-based strategies; and monitoring and evaluation of effectiveness. Observation data captured nurses using the App with 44.7% (n = 17) of eligible inpatients. Cognitive screening was completed at least once for each patient, with 146 risk assessments recorded. Interview data indicated the App's acceptability was enhanced by familiarity and perceived benefits, but hindered by perceived increases in workload, inconsistent use, pressure to use the App and resistance to change. Feasibility and usability were enhanced by easy navigation, and clear and useful content, but hindered by unclear expectations, unfamiliarity and device-related factors.

Conclusions: The App provided an evidence-based tool that was, overall, considered feasible and acceptable to support best practice. Findings provide guidance to enhance usability for future implementation.

Relevance To Clinical Practice: Co-development using best evidence and key stakeholders enabled creation of a novel, feasible and acceptable technology. Real-time access to assessment tools and tailored knowledge supported nurses' clinical decision-making; workload and unfamiliarity were barriers to use.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1111/jocn.14874DOI Listing
August 2019

Appearance comparison and other appearance-related influences on body dissatisfaction in everyday life.

Body Image 2019 Mar 9;28:101-109. Epub 2019 Jan 9.

School of Psychology, Deakin University, Burwood, Victoria, 3125, Australia; Cairnmillar Institute, Hawthorn East, Victoria, 3123, Australia.

Although appearance comparisons, self-monitoring, and appearance-related comments have been linked to body dissatisfaction in prior studies, the combined and unique influences of these variables on state body dissatisfaction in daily life has yet to be explored. The present study addressed this gap, and also evaluated whether these state-based effects were stronger for individuals with trait-level body image disturbances (internalization and body dissatisfaction). Eighty-four women completed baseline measures of trait internalization and body dissatisfaction, and then reported momentary experiences of body dissatisfaction, appearance self-monitoring, appearance-related comments, and appearance-based comparisons at up to 10 random times daily for seven days. Multilevel analyses confirmed that both appearance comparisons and commentary (both negative and positive) were predictive of changes in state body dissatisfaction when modelled individually as well as in a combined (full) model. Appearance self-monitoring was not a significant predictor, either individually or in the full model. These within-person relationships were not moderated by individual differences in trait body dissatisfaction and internalization of appearance standards. Accordingly, experiences of body dissatisfaction in daily life may be a common reaction to negative appearance comments and unflattering comparisons, yet positive comments and/or efforts to avoid appearance-based comparisons may have a positive effect on one's body image.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.bodyim.2019.01.002DOI Listing
March 2019

A Mobile App-Based Intervention for Depression: End-User and Expert Usability Testing Study.

JMIR Ment Health 2018 Aug 23;5(3):e54. Epub 2018 Aug 23.

School of Psychology, Deakin University, Geelong, Australia.

Background: Despite the growing number of mental health apps available for smartphones, the perceived usability of these apps from the perspectives of end users or health care experts has rarely been reported. This information is vital, particularly for self-guided mHealth interventions, as perceptions of navigability and quality of content are likely to impact participant engagement and treatment compliance.

Objective: The aim of this study was to conduct a usability evaluation of a personalized, self-guided, app-based intervention for depression.

Methods: Participants were administered the System Usability Scale and open-ended questions as part of a semistructured interview. There were 15 participants equally divided into 3 groups: (1) individuals with clinical depression who were the target audience for the app, (2) mental health professionals, and (3) researchers who specialize in the area of eHealth interventions and/or depression research.

Results: The end-user group rated the app highly, both in quantitative and qualitative assessments. The 2 expert groups highlighted the self-monitoring features and range of established psychological treatment options (such as behavioral activation and cognitive restructuring) but had concerns that the amount and layout of content may be difficult for end users to navigate in a self-directed fashion. The end-user data did not confirm these concerns.

Conclusions: Encouraging participant engagement via self-monitoring and feedback, as well as personalized messaging, may be a viable way to maintain participation in self-guided interventions. Further evaluation is necessary to determine whether levels of engagement with these features enhance treatment effects.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.2196/mental.9445DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6127496PMC
August 2018

Motive- and appearance awareness-based explanations for body (dis)satisfaction following exercise in daily life.

Br J Health Psychol 2018 11 24;23(4):982-999. Epub 2018 Jul 24.

College of Medicine, Biology and Environment, Australian National University, Canberra, Australian Capital Territory, Australia.

Objective: Although exercise is typically found to improve body satisfaction, this effect may be reduced or even reversed for trait body-dissatisfied individuals. The reasons for this remain unclear. This study tested the possibility that these effects are due to appearance-related motives and/or increased appearance awareness post-exercise.

Method: Participants included 178 women who completed baseline measures of trait body dissatisfaction, and then completed an experience sampling phase in which they self-reported state body satisfaction and appearance awareness levels, and recent exercise experiences at six time-points daily for 10 days.

Results: Trait body-dissatisfied individuals were more likely to exercise for appearance-related reasons, and experienced less of an increase in state body satisfaction post-exercise. Appearance-motivated exercise also increased appearance awareness. After controlling for appearance motives, the moderating effect of trait body dissatisfaction on the exercise-state body satisfaction relationship reduced to non-significance.

Conclusions: Collectively, the present findings offer some support for both motive- and appearance awareness-based explanations for the reduced benefits of exercise on body satisfaction exhibited in individuals with trait body dissatisfaction. Targeting the reasons for exercise and what one focuses on during exercise may be viable ways to overcome potential negative impacts of exercise on body image for these individuals. Statement of contribution What is already known on this subject? While the physical and psychological benefits of exercise are well established, recent findings suggest that these benefits for body satisfaction may be reduced (and possibly reversed) for individuals with elevated trait body dissatisfaction. The reasons for this moderating effect remain unclear. What does this study add? Trait body-dissatisfied individuals more often engaged in exercise for appearance-related reasons. Appearance motives for exercise are associated with smaller body satisfaction gains post-exercise. Reduced body satisfaction was also linked to increased appearance awareness post-exercise.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1111/bjhp.12334DOI Listing
November 2018

The Cerebellar GABAR System as a Potential Target for Treating Alcohol Use Disorder.

Handb Exp Pharmacol 2018 ;248:113-156

Department of Integrative Physiology and Neuroscience, College of Veterinary Medicine, Washington State University, Pullman, WA, USA.

In the brain, fast inhibitory neurotransmission is mediated primarily by the ionotropic subtype of the gamma-aminobutyric acid (GABA) receptor subtype A (GABAR). It is well established that the brain's GABAR system mediates many aspects of neurobehavioral responses to alcohol (ethanol; EtOH). Accordingly, in both preclinical studies and some clinical scenarios, pharmacologically targeting the GABAR system can alter neurobehavioral responses to acute and chronic EtOH consumption. However, many of the well-established interactions of EtOH and the GABAR system have been identified at concentrations of EtOH ([EtOH]) that would only occur during abusive consumption of EtOH (≥40 mM), and there are still inadequate treatment options for prevention of or recovery from alcohol use disorder (AUD, including abuse and dependence). Accordingly, there is a general acknowledgement that more research is needed to identify and characterize: (1) neurobehavioral targets of lower [EtOH] and (2) associated brain structures that would involve such targets in a manner that may influence the development and maintenance of AUDs.Nearly 15 years ago it was discovered that the GABAR system of the cerebellum is highly sensitive to EtOH, responding to concentrations as low as 10 mM (as would occur in the blood of a typical adult human after consuming 1-2 standard units of EtOH). This high sensitivity to EtOH, which likely mediates the well-known motor impairing effects of EtOH, combined with recent advances in our understanding of the role of the cerebellum in non-motor, cognitive/emotive/reward processes has renewed interest in this system in the specific context of AUD. In this chapter we will describe recent advances in our understanding of cerebellar processing, actions of EtOH on the cerebellar GABAR system, and the potential relationship of such actions to the development of AUD. We will finish with speculation about how cerebellar specific GABAR ligands might be effective pharmacological agents for treating aspects of AUD.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/164_2018_109DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6222009PMC
June 2019

An ecological momentary assessment of the effect of fasting during Ramadan on disordered eating behaviors.

Appetite 2018 08 23;127:44-51. Epub 2018 Apr 23.

Melbourne School of Psychological Sciences, University of Melbourne, Victoria, 14-20 Blackwood Street, VIC 3010, Melbourne, Australia. Electronic address:

Dietary restriction contributes to disordered eating (DE) behaviors and associated cognitions. However, it is unclear how these outcomes are impacted by dietary restriction for religious purposes, such as fasting observed by Muslims during Ramadan. Using ecological momentary assessment, this study assessed the impact of Ramadan fasting on DE behaviors and correlates. Muslim participants fasting during Ramadan (n = 28) and a control group of non-fasting participants (n = 74) completed baseline measures assessing demographic characteristics and eating pathology. A mobile phone application then prompted participants six times per day for seven days to self-report on dietary restriction efforts, body satisfaction, temptation to eat unhealthily, feelings of guilt or shame following food, and DE behaviors including bingeing, vomiting, and other purging behaviors (use of laxatives, diuretics, or diet pills). After controlling for eating pathology, multilevel modeling indicated that, as expected, the Ramadan fasting group spent significantly more time restricting food intake than the non-fasting group. The Ramadan fasting group also experienced significantly greater temptation to eat unhealthily than their non-fasting counterparts. However, this difference disappeared once models were adjusted for differences in time spent restricting food intake. There were no other significant differences between the groups on any DE variables. These findings suggest that while dietary restriction for health or appearance-related reasons is a known contributor to DE, dietary restriction for religious purposes, such as that observed during the practice of Ramadan, may not confer increased risk of DE symptoms.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.appet.2018.04.017DOI Listing
August 2018

Do women with greater trait body dissatisfaction experience body dissatisfaction states differently? An experience sampling study.

Body Image 2018 Jun 2;25:1-8. Epub 2018 Feb 2.

School of Psychological Sciences, University of Melbourne, Victoria, 3010, Australia.

The present study evaluated the relation of key features of state body dissatisfaction experiences - inertia, instability from moment-to-moment, and average level across time-points - to trait body dissatisfaction and/or eating disorder risk. Participants included 161 women who completed measures of trait body dissatisfaction and disordered eating pathology, and then completed reported state body dissatisfaction and contextual influences (binge eating, dietary restraint, exercise, and appearance comparison behaviors) 6 times daily for 7 days. Results indicated that individuals with elevated trait body dissatisfaction were reliably different from those with healthier body image in terms of average state body dissatisfaction ratings, but not for inertia or instability. State mean and trait body dissatisfaction uniquely predicted eating pathology, although their predictive accuracy for clinical caseness was comparable. Cost vs. benefit of using state body image data for understanding trait body image and eating pathology is discussed.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.bodyim.2018.01.004DOI Listing
June 2018

The sigma-1 receptor modulates methamphetamine dysregulation of dopamine neurotransmission.

Nat Commun 2017 12 20;8(1):2228. Epub 2017 Dec 20.

Department of Neuroscience, University of Florida, Gainesville, FL, 32611, USA.

Dopamine neurotransmission is highly dysregulated by the psychostimulant methamphetamine, a substrate for the dopamine transporter (DAT). Through interactions with DAT, methamphetamine increases extracellular dopamine levels in the brain, leading to its rewarding and addictive properties. Methamphetamine also interacts with the sigma-1 receptor (σR), an inter-organelle signaling modulator. Using complementary strategies, we identified a novel mechanism for σR regulation of dopamine neurotransmission in response to methamphetamine. We found that σR activation prevents methamphetamine-induced, DAT-mediated increases in firing activity of dopamine neurons. In vitro and in vivo amperometric measurements revealed that σR activation decreases methamphetamine-stimulated dopamine efflux without affecting basal dopamine neurotransmission. Consistent with these findings, σR activation decreases methamphetamine-induced locomotion, motivated behavior, and enhancement of brain reward function. Notably, we revealed that the σR interacts with DAT at or near the plasma membrane and decreases methamphetamine-induced Ca signaling, providing potential mechanisms. Broadly, these data provide evidence for σR regulation of dopamine neurotransmission and support the σR as a putative target for the treatment of methamphetamine addiction.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/s41467-017-02087-xDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5738444PMC
December 2017

Transient Hypoxemia Chronically Disrupts Maturation of Preterm Fetal Ovine Subplate Neuron Arborization and Activity.

J Neurosci 2017 12 31;37(49):11912-11929. Epub 2017 Oct 31.

Department of Pediatrics and

Preterm infants are at risk for a broad spectrum of neurobehavioral disabilities associated with diffuse disturbances in cortical growth and development. During brain development, subplate neurons (SPNs) are a largely transient population that serves a critical role to establish functional cortical circuits. By dynamically integrating into developing cortical circuits, they assist in consolidation of intracortical and extracortical circuits. Although SPNs reside in close proximity to cerebral white matter, which is particularly vulnerable to oxidative stress, the susceptibility of SPNs remains controversial. We determined SPN responses to two common insults to the preterm brain: hypoxia-ischemia and hypoxia. We used a preterm fetal sheep model using both sexes that reproduces the spectrum of human cerebral injury and abnormal cortical growth. Unlike oligodendrocyte progenitors, SPNs displayed pronounced resistance to early or delayed cell death from hypoxia or hypoxia-ischemia. We thus explored an alternative hypothesis that these insults alter the maturational trajectory of SPNs. We used DiOlistic labeling to visualize the dendrites of SPNs selectively labeled for complexin-3. SPNs displayed reduced basal dendritic arbor complexity that was accompanied by chronic disturbances in SPN excitability and synaptic activity. SPN dysmaturation was significantly associated with the level of fetal hypoxemia and metabolic stress. Hence, despite the resistance of SPNs to insults that trigger white matter injury, transient hypoxemia disrupted SPN arborization and functional maturation during a critical window in cortical development. Strategies directed at limiting the duration or severity of hypoxemia during brain development may mitigate disturbances in cerebral growth and maturation related to SPN dysmaturation. The human preterm brain commonly sustains blood flow and oxygenation disturbances that impair cerebral cortex growth and cause life-long cognitive and learning disabilities. We investigated the fate of subplate neurons (SPNs), which are a master regulator of brain development that plays critical roles in establishing cortical connections to other brain regions. We used a preterm fetal sheep model that reproduces key features of brain injury in human preterm survivors. We analyzed the responses of fetal SPNs to transient disturbances in fetal oxygenation. We discovered that SPNs are surprisingly resistant to cell death from low oxygen states but acquire chronic structural and functional changes that suggest new strategies to prevent learning problems in children and adults that survive preterm birth.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1523/JNEUROSCI.2396-17.2017DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5719974PMC
December 2017

Dissociation between wanting and liking for alcohol and caffeine: A test of the Incentive Sensitisation Theory.

J Psychopharmacol 2017 07 19;31(7):927-933. Epub 2017 Jun 19.

1 Faculty of Health, School of Psychology, Deakin University, Melbourne, VIC, Australia.

Limited human studies have directly tested the dissociation between wanting and liking with human substance users, a core tenet of the Incentive Sensitisation Theory (IST). The aim of this study is to test the dissociation between wanting and liking in humans across two commonly used licit substances, alcohol and caffeine. The STRAP-R (Sensitivity To Reinforcement of Addictive and other Primary Rewards) questionnaire was administered to 285 alcohol users (mean age=33.30, SD= 8.83) and 134 coffee users (mean age=33.05, SD=8.10) ranging in their levels of substance use to assess wanting and liking. Findings showed that in high risk alcohol users wanting may drive alcohol consumption more so than liking, compared with low risk alcohol users. However, wanting and liking did not significantly dissociate as alcohol consumption increased. These findings partially support IST. Additionally, IST was not supported in coffee users. It is possible that caffeine functions differently at the neurological level compared with alcohol, perhaps explaining the lack of dissociation emerging in coffee users as caffeine use increased. Nevertheless, the current study makes several contributions to IST research. Future studies should focus on utilising the STRAP-R with a clinically dependent sample to test the dissociation between wanting and liking.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1177/0269881117711711DOI Listing
July 2017

Regression tree analysis of ecological momentary assessment data.

Health Psychol Rev 2017 09 6;11(3):235-241. Epub 2017 Jul 6.

a eMental Health Unit , School of Psychology, Deakin University , Burwood , Australia.

An increasingly popular form of data collection in health psychology research is Ecological Momentary Assessment (EMA); that is, using diaries or smartphones to collect intensive longitudinal data. This method is increasingly applied to the study of relationships between state-based aspects of individuals' functioning and health outcomes (e.g., binge eating, alcohol use). Analysis of such data is challenging and regression tree modelling (RTM) may be a useful alternative to multilevel modelling for investigating the association between a set of explanatory variables and a continuous outcome. Furthermore, RTM outputs 'decision trees' that could be used by health practitioners to guide assessment and tailor intervention. In contrast to regression, RTM is able to easily accommodate many complex, higher-order interactions between predictor variables (without the need to create explicit interaction terms). These benefits make the technique useful for those interested in monitoring and intervening upon health and psychological outcomes (e.g., mood, eating behaviour, risky alcohol use, and treatment adherence). Using real data, this paper demonstrates both the benefits and limitations of RTM and how to extend these models to accommodate analysis of nested data; that is, data that arise from EMA where repeated observations are nested within individuals.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1080/17437199.2017.1343677DOI Listing
September 2017

Impact of Roux-en-Y gastric bypass surgery on appetite, alcohol intake behaviors, and midbrain ghrelin signaling in the rat.

Obesity (Silver Spring) 2017 07 12;25(7):1228-1236. Epub 2017 May 12.

Department of Integrative Physiology and Neuroscience, Washington State University, Pullman, Washington, USA.

Objective: Roux-en-Y gastric bypass (RYGB) surgery reduces appetite and stimulates new onset alcohol misuse; however, the genesis of these behavioral changes is unclear. This study is hypothesized that new onset alcohol intake is a behavioral adaptation that occurs secondary to reduced appetite and correlates with altered central ghrelin signaling.

Methods: Hedonic high-fat diet (HFD) intake was evaluated prior to the assessment of alcohol intake behaviors in RYGB and control rats. Measurements were also taken of circulating ghrelin and ghrelin receptor (GHSR) regulation of neuronal firing in ventral tegmental area (VTA) dopamine (DA) neurons.

Results: RYGB rats displayed reduced HFD intake relative to controls. Sham and RYGB rats consumed more alcohol and preferred lower concentrations of alcohol, whereas only RYGB rats escalated alcohol intake during acute withdrawal. Remarkably, GHSR activity, independent of peripheral ghrelin release, set the tonic firing of VTA DA neurons, a response selectively diminished in RYGB rats.

Conclusions: This study indicates that gut manipulations lead to increased alcohol intake, whereas RYGB promotes behaviors that may maintain alcohol misuse. Reductions in hedonic feeding and diminished GHSR control of VTA firing further distinguish gut manipulation from complete bypass and present a potential mechanism linking reduced appetite with alcohol misuse after RYGB surgery.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1002/oby.21839DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6029700PMC
July 2017

Recreational concentrations of alcohol enhance synaptic inhibition of cerebellar unipolar brush cells via pre- and postsynaptic mechanisms.

J Neurophysiol 2017 07 5;118(1):267-279. Epub 2017 Apr 5.

Department of Integrative Physiology and Neuroscience, College of Veterinary Medicine, Washington State University, Pullman, Washington; and

Variation in cerebellar sensitivity to alcohol/ethanol (EtOH) is a heritable trait associated with alcohol use disorder in humans and high EtOH consumption in rodents, but the underlying mechanisms are poorly understood. A recently identified cellular substrate of cerebellar sensitivity to EtOH, the GABAergic system of cerebellar granule cells (GCs), shows divergent responses to EtOH paralleling EtOH consumption and motor impairment phenotype. Although GCs are the dominant afferent integrator in the cerebellum, such integration is shared by unipolar brush cells (UBCs) in vestibulocerebellar lobes. UBCs receive both GABAergic and glycinergic inhibition, both of which may mediate diverse neurological effects of EtOH. Therefore, the impact of recreational concentrations of EtOH (~10-50 mM) on GABA receptor (GABAR)- and glycine receptor (GlyR)-mediated spontaneous inhibitory postsynaptic currents (sIPSCs) of UBCs in cerebellar slices was characterized. Sprague-Dawley rat (SDR) UBCs exhibited sIPSCs mediated by GABARs, GlyRs, or both, and EtOH dose-dependently (10, 26, 52 mM) increased their frequency and amplitude. EtOH increased the frequency of glycinergic and GABAergic sIPSCs and selectively enhanced the amplitude of glycinergic sIPSCs. This GlyR-specific enhancement of sIPSC amplitude resulted from EtOH actions at presynaptic Golgi cells and via protein kinase C-dependent direct actions on postsynaptic GlyRs. The magnitude of EtOH-induced increases in UBC sIPSC activity varied across SDRs and two lines of mice, in parallel with their respective alcohol consumption/motor impairment phenotypes. These data indicate that Golgi cell-to-UBC inhibitory synapses are targets of EtOH, which acts at pre- and postsynaptic sites, via Golgi cell excitation and direct GlyR enhancement. Genetic variability in cerebellar alcohol/ethanol sensitivity (ethanol-induced ataxia) predicts ethanol consumption phenotype in rodents and humans, but the cellular and molecular mechanisms underlying genetic differences are largely unknown. Here it is demonstrated that recreational concentrations of alcohol (10-30 mM) enhance glycinergic and GABAergic inhibition of unipolar brush cells through increases in glycine/GABA release and postsynaptic enhancement of glycine receptor-mediated responses. Ethanol effects varied across rodent genotypes parallel to ethanol consumption and motor sensitivity phenotype.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1152/jn.00963.2016DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5498730PMC
July 2017

The pleasure of making a difference: Perceived social contribution explains the relation between extraverted behavior and positive affect.

Emotion 2017 08 13;17(5):794-810. Epub 2017 Feb 13.

Melbourne School of Psychological Sciences, The University of Melbourne.

Why are trait extraversion and extraverted behaviors both associated with greater positive affect? Across 3 studies, we examined whether 2 aspects of social experience-perceived social contribution and social power-mediate the relation between extraversion and positive affect. Study 1 (N = 205) showed that trait measures of social contribution and power mediated the relation between trait extraversion and trait positive affect. Study 2 (N = 78) showed that state social contribution and power helped to explain the greater levels of state positive affect reported by participants who were instructed to enact extraverted behaviors. Finally, Study 3 (N = 62) showed that social contribution and power mediated the relation between natural fluctuations in extraverted behavior and positive affect states in daily life. In all 3 studies, multiple-mediator models showed that social contribution, but not power, independently mediated the relations that trait and state extraversion had with positive affect. This suggests that perceptions of positive influence-more so than a general sense of power-help to explain why extraverts and extraverted moments are happier. We link these findings to emerging trends in the study of personality dynamics and the potential benefits of acting "out of character." (PsycINFO Database Record
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1037/emo0000273DOI Listing
August 2017

A Person-by-Situation Account of Why Some People More Frequently Engage in Upward Appearance Comparison Behaviors in Everyday Life.

Behav Ther 2017 01 8;48(1):19-28. Epub 2016 Oct 8.

Deakin University.

Although the influence of stable, trait-like factors (such as trait body dissatisfaction and appearance internalization) on instances of appearance comparison has been well documented, the additive and interactive influence of contextual factors (such as one's current body satisfaction) on comparison behaviors is unknown. Therefore, the present study tested a Person×Situation model in which both state and trait body image variables interacted to predict engagement in various forms of comparison (upward, downward, and lateral). Participants included 161 women who completed a baseline measure of trait body dissatisfaction and internalization, and then completed, via an iPhone app, an ecological momentary assessment phase in which they reported momentary experiences of mood and comparison behaviors at up to 6 random times per day for 7days. Multilevel analyses revealed that upward comparisons (comparisons against more attractive people) were more likely for individuals with heightened trait and/or state negative body image, but these predictive effects of state and trait on appearance comparisons appear largely independent of each other. Furthermore, neither state nor trait body image variables were related to the other forms of comparison, and time lag at the state-level between predictor and outcome did not seem to influence the strength of these associations. Present findings are consistent with the notion that how an individual feels in the moment about their appearance may influence engagement in deleterious appearance behaviors. However, further testing is needed to confirm these causal hypotheses.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.beth.2016.09.007DOI Listing
January 2017

Using dynamic factor analysis to provide insights into data reliability in experience sampling studies.

Psychol Assess 2017 Sep 7;29(9):1120-1128. Epub 2016 Nov 7.

School of Psychology, Deakin University.

The past 2 decades have seen increasing use of experience sampling methods (ESMs) to gain insights into the daily experience of affective states (e.g., its variability, as well as antecedents and consequences of temporary shifts in affect). Much less attention has been given to methodological challenges, such as how to ensure reliability of test scores obtained using ESM. The present study demonstrates the use of dynamic factor analysis (DFA) to quantify reliability of test scores in ESM contexts, evaluates the potential impact of unreliable test scores, and seeks to identify characteristics of individuals that may account for their unreliable test scores. One hundred twenty-seven participants completed baseline measures (demographics and personality traits), followed by a 7-day ESM phase in which positive and negative state affect were measured up to 6 times per day. Analyses showed that although at the sample level, scores on these affect measures exhibited adequate levels of reliability, up to one third of participants failed to meet conventional standards of reliability. Where these low reliability estimates were not significantly associated with personality factors, they could-in some cases-be explained by model misspecification where a meaningful alternative structure was available. Despite these potential differences in factor structure across participants, subsequent modeling with and without these "unreliable" cases showed similar substantive results. Hence, the present findings suggest typical analyses based on ESM data may be robust to individual differences in data structure and/or quality. Ways to augment the DFA approach to better understand unreliable cases are discussed. (PsycINFO Database Record
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1037/pas0000411DOI Listing
September 2017

Responses to Predictable versus Random Temporally Complex Stimuli from Single Units in Auditory Thalamus: Impact of Aging and Anesthesia.

J Neurosci 2016 10;36(41):10696-10706

Southern Illinois University School of Medicine, Department of Pharmacology, Springfield, Illinois 62794

Human aging studies suggest that an increased use of top-down knowledge-based resources would compensate for degraded upstream acoustic information to accurately identify important temporally rich signals. Sinusoidal amplitude-modulated (SAM) stimuli have been used to mimic the fast-changing temporal features in speech and species-specific vocalizations. Single units were recorded from auditory thalamus [medial geniculate body (MGB)] of young awake, aged awake, young anesthetized, and aged anesthetized rats. SAM stimuli were modulated between 2 and 1024 Hz with the modulation frequency (fm) changed randomly (RAN) across trials or sequentially (SEQ) after several repeated trials. Units were found to be RAN-preferring, SEQ-preferring, or nonselective based on total firing rate. Significant anesthesia and age effects were found. The majority (86%) of young anesthetized units preferred RAN SAM stimuli; significantly fewer young awake units (51%, p < 0.0001) preferred RAN SAM signals with 16% preferring SEQ SAM. Compared with young awake units, there was a significant increase of aged awake units preferring SEQ SAM (30%, p < 0.05). We examined RAN versus SEQ differences across fms by measuring selective fm areas under the rate modulation transfer function curve. The largest age-related differences from awake animals were found for mid-to-high fms in MGB units, with young units preferring RAN SAM while aged units showed a greater preference for SEQ-presented SAM. Together, these findings suggest that aged MGB units/animals employ increased top-down mediated stimulus context to enhance processing of "expected" temporally rich stimuli, especially at more challenging higher fms.

Significance Statement: Older individuals compensate for impaired ascending acoustic information by increasing use of cortical cognitive and attentional resources. The interplay between ascending and descending influences in the thalamus may serve to enhance the salience of speech signals that are degraded as they ascend to the cortex. The present findings demonstrate that medial geniculate body units from awake rats show an age-related preference for predictable modulated signals relative to randomly presented signals, especially at higher, more challenging modulation frequencies. Conversely, units from anesthetized animals, with little top-down influences, strongly preferred randomly presented modulated sequences. These results suggest a neuronal substrate for an age-related increase in experience/attentional-based influences in processing temporally complex auditory information in the auditory thalamus.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1523/JNEUROSCI.1454-16.2016DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5059434PMC
October 2016
-->