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Item The affective primacy hypothesis: Affective or cognitive processing of optimally and suboptimally presented primes?(Ubiquity Press, 1996) Kemps, Eva Bertha; Erauw, K; Vandierendonck, AndreThe aim of the present study was to pursue the research on the affective primacy hypothesis, which claims that positive and negative affective reactions can be evoked with minimal stimulus input and virtually no cognitive processing (Zajonc, 1980). In line with Murphy and Zajonc (1993) a priming paradigm was used. The present work is basically a replication of their study in which the effects of affective priming under very brief (suboptimal - 4 ms) and longer (optimal - 1000 ms) exposure durations were compared, but using two additional exposure durations: 30 ms and 100 ms. Like Murphy and Zajonc, facial expressions were used as affective primes in addition to pictures which portrayed scenes and situations of everyday life. These were obtained in a preliminary study. Contrary to Murphy and Zajonc's results, the affective primes only produced significant shifts in subjects' preferential judgements of novel stimuli at longer exposure durations. At suboptimal exposures the novel stimuli were not judged differentially when primed with positive or negative affect. This was true for both facial expressions and pictures. Facial expressions influenced the liking ratings of the ideographs only at exposure durations of 30 ms and longer; pictures not until they were exposed for at least 100 ms. Thus, pictures depicting daily events require longer exposure durations than facial expressions in order to elicit an affective reaction. These results however do not provide any clear-cut evidence in support of the affective primacy hypothesis. Instead, they seem to suggest that affective stimuli do not evoke an affective reaction without additional cognitive processing, a conclusion that is supported by LeDoux’s theory of affective-cognitive interaction in the brain.Item Apologies demanded yet devalued: Normative dilution in the age of apology(Elsevier, 2015-07) Okimoto, Tyler Gene; Wenzel, Michael; Hornsey, Matthew JDramatic increases in the issuance of political apologies over the last two decades mean that we now live in the “age of apology”. But what does this surge in frequency mean for the effectiveness of intergroup apologies in promoting forgiveness? In the current research we propose a paradoxical “normative dilution” effect whereby behavioral norms increase the perceived appropriateness of an action while at the same time reducing its symbolic value. We experimentally manipulated the salience of the age-of-apology norm prior to assessing participant (N=128) reactions to past unjust treatment of ingroup prisoners of war by the Japanese during World War II. The apologetic norm increased victim group members’ desire for an apology in response to the harm. However, after reading the actual apology, the invocation of the norm decreased perceived apology sincerity and subsequent willingness to forgive. Thus, although apologetic trends may suggest greater contemporary interest in seeking reconciliation and harmony, their inflationary use risks devaluing apologies and undermining their effectiveness.Item Approach bias for food cues in obese individuals(Taylor & Francis, 2014-11-03) Kemps, Eva Bertha; Tiggemann, MarikaThis study aimed to investigate the existence of an approach bias for food cues in obese individuals. A community sample of 56 obese women and 56 normal weight controls completed an approach–avoidance variant of the implicit association task. The obese participants were faster to respond to trials that paired food words with approach words, and trials that paired non-food words with avoid words, than the converse pairings, thus, demonstrating an approach bias for food. This bias was evident for both high caloric and low caloric food words, and was not attributable to a state of deprivation or feelings of hunger. By contrast, the normal weight controls did not show any such bias. The results are consistent with recent neurocognitive perspectives of obesity. At a practical level, approach biases for food may present a potential target for modifying (excessive) food intake.Item Association between dietary saccharide intake and self-reported memory performance in middle-aged adults(Cambridge University Press, 2009) Best, Talitha Marie; Kemps, Eva Bertha; Bryan, JanetThe aims of the present study were to assess dietary intake of saccharides in middle-aged adults, and to determine whether intakes of these sugar nutrients were related to self-reported memory performance. A population-based sample of 1183 men and women (aged 40-60 years) completed questionnaires assessing everyday memory function. Dietary intake status of saccharides was estimated using a self-completed, quantified FFQ. After controlling for demographic and health measures (for example, time spent exercising, smoking and alcohol consumption), saccharide intake was related to better self-reported memory functioning. Thus, longer-term intakes of saccharides through the usual diet may be positively related to perceived memory performance in mid-life.Item Asymmetric neural responses for facial expressions and anti-expressions(Elsevier, 2018-09-05) Gwinn, O Scott; Matera, Courtney N; O'Neil, Sean F; Webster, Michael AFace recognition requires identifying both the invariant characteristics that distinguish one individual from another and the variations within the individual that correspond to emotional expressions. Both have been postulated to be represented via a norm-based code, in which identity or expression are represented as deviations from an average or neutral prototype. We used Fast Periodic Visual Stimulation (FPVS) with electroencephalography (EEG) to compare neural responses for neutral faces, expressions and anti-expressions. Anti-expressions are created by projecting an expression (e.g. a happy face) through the neutral face to form the opposite facial shape (anti-happy). Thus expressions and anti-expressions differ from the norm by the same “configural” amount and thus have equivalent but opposite status with regard to their shape, but differ in their ecological validity. We examined whether neural responses to these complementary stimulus pairs were equivalent or asymmetric, and also tested for norm-based coding by comparing whether stronger responses are elicited by expressions and anti-expressions than neutral faces. Observers viewed 20 s sequences of 6 Hz alternations of neutral faces and expressions, neutral faces and anti-expressions, and expressions and anti-expressions. Responses were analyzed in the frequency domain. Significant responses at half the frequency of the presentation rate (3 Hz), indicating asymmetries in responses, were observed for all conditions. Inversion of the images reduced the size of this signal, indicating these asymmetries are not solely due to differences in the low-level properties of the images. While our results do not preclude a norm-based code for expressions, similar to identity, this representation (as measured by the FPVS EEG responses) may also include components sensitive to which configural distortions form meaningful expressions.Item Attentional bias modification encourages healthy eating(Elsevier, 2014-01) Kakoschke, Naomi; Kemps, Eva Bertha; Tiggemann, MarikaThe continual exposure to unhealthy food cues in the environment encourages poor dietary habits, in particular consuming too much fat and sugar, and not enough fruit and vegetables. According to Berridge’s (1996) model of food reward, unhealthy eating is a behavioural response to biased attentional processing. The present study used an established attentional bias modification paradigm to discourage the consumption of unhealthy food and instead promote healthy eating. Participants were 146 undergraduate women who were randomly assigned to two groups: one was trained to direct their attention toward pictures of healthy food (‘attend healthy’ group) and the other toward unhealthy food (‘attend unhealthy’ group). It was found that participants trained to attend to healthy food cues demonstrated an increased attentional bias for such cues and ate relatively more of the healthy than unhealthy snacks compared to the ‘attend unhealthy’ group. Theoretically, the results support the postulated link between biased attentional processing and consumption (Berridge, 2009). At a practical level, they offer potential scope for interventions that focus on eating well.Item Attentional Retraining Can Reduce Chocolate Consumption(American Psychological Association, 2014-03) Kemps, Eva Bertha; Tiggemann, Marika; Orr, Jenna; Grear, JustineThere is emerging evidence that attentional biases are related to the consumption of substances such as alcohol and tobacco, and that attentional bias modification can reduce unwanted consumption of these substances. We present evidence for the first time that the same logical argument applies in the food and eating domain. We conducted two experiments which used a modified dot probe paradigm to train undergraduate women to direct their attention toward (‘attend’) or away from (‘avoid’) food cues (i.e., pictures of chocolate). In Experiment 1, attentional bias for chocolate cues increased in the ‘attend’ group, and decreased in the ‘avoid’ group. Experiment 2 showed that these training effects generalised to novel, previously unseen, chocolate pictures. Importantly, attentional re-training affected chocolate consumption and craving. In both experiments, participants in the ‘avoid’ group ate less chocolate in a so-called taste test than did those in the ‘attend’ group. Additionally, in Experiment 2, but not in Experiment 1, the ‘attend’ group reported stronger chocolate cravings following training, whereas the ‘avoid’ group reported less intense cravings. The results support predictions of cognitive-motivational models of craving and consumption that attentional biases play a causal role in consumption behaviour. Furthermore, they present a promising avenue for tackling unwanted food cravings and (over)eating. Keywords: food cues; attentional bias modification; dot probe task; consumption; cravingItem Behavioural measurements of sleep onset: A comparison of two devices.(20042004) Connelly, LiamDaytime fatigue as a result of reducing nocturnal sleep in order to work longer hours is a common problem in modem societies. Recent research has shown that a nap of 10 minutes in length can increase people's awareness and subsequent performance. However, the problem arises of how to undertake a 10 minute nap without over-sleeping. Behavioural measurements of sleep onset may provide the answer, as they are an inexpensive and convenient way to measure sleep onset. This study examined which out of a passive and active behavioural device was the best measure of sleep onset as defined by polysornnograhic sleep onset. The present study used a repeated measures design which involved six participants who were measured using both the active and passive devices, each for three days. On each occasion the participants were measured, they undertook a total of nine sleep onset sessions. Six of the sleep onset sessions involved participants falling asleep whilst using the device, while three sessions involved them falling asleep without the device (control condition). The results revealed no significant difference between the active and passive device both for their discrepancy magnitude from polysornnograhic sleep onset and for their discrepancy standard deviations. In addition there were no learning effects for the devices, and the devices did not prolong sleep onset compared to the control condition. The results obtained suggested that both devices were effective measures of sleep onset. However, further research will need to be undertaken to address the limitations of this study and provide a more detailed analysis of the two devices before the full extent of their effectiveness can be determined.Item Benchmarking Aided Decision Making in a Signal Detection Task(Sage, 2017-03-15) Bartlett, Megan; McCarley, Jason SObjective: A series of experiments examined human operators’ strategies for interacting with highly (93%) reliable automated decision aids in a binary signal detection task. Background: Operators often interact with automated decision aids in a suboptimal way, achieving performance levels lower than predicted by a statistically ideal model of information integration. To better understand operators’ inefficient use of decision aids, we compared participants’ automation-aided performance levels with the predictions of seven statistical models of collaborative decision making. Method: Participants performed a binary signal detection task that asked them to classify random dot images as either blue or orange dominant. They made their judgments either unaided or with assistance from a 93% reliable automated decision aid that provided either graded (Experiments 1 and 3) or binary (Experiment 2) cues. We compared automation-aided performance with the predictions of seven statistical models of collaborative decision making, including a statistically optimal model and Robinson and Sorkin’s contingent criterion model. Results and Conclusion: Automation-aided sensitivity hewed closest to the predictions of the two least efficient collaborative models, well short of statistically ideal levels. Performance was similar whether the aid provided graded or binary judgments. Model comparisons identified potential strategies by which participants integrated their judgments with the aid’s. Application: Results lend insight into participants’ automation-aided decision strategies and provide benchmarks for predicting automation-aided performance levels.Item Biased attentional processing of food cues and modification in obese individuals(American Psychology Association, 2014-11) Kemps, Eva Bertha; Tiggemann, Marika; Hollitt, Sarah JaneThis paper reports two experiments designed to investigate and modify biased attentional processing of food cues in obesity. Experiment 1: Experiment 1 used a dot probe task to show a food-related attentional bias in 58 obese women, relative to a comparison sample of normal weight controls. Experiment 2: Experiment 2 examined whether this bias can be modified. Using a modified dot probe task, 96 obese women were trained to attend to, or to avoid, food pictures. Attentional bias for food increased in the attend group, and decreased in the avoid group. The attentional retraining effects generalized to an independent measure of biased information processing, such that participants in the avoid group produced relatively fewer food than animal words on a subsequent word stem completion task than those in the attend group. Conclusion: The results extend the application of attentional bias modification from anxiety and addiction to obesity. They also offer potential scope for tackling pathological (over)eating.Item Biological and Psychosocial Processes in the Development of Children’s Appetitive Traits: Insights from Developmental Theory and Research(MDPI, 2018-05-29) Russell, Catherine G; Russell, AlanThere has been increasing concern expressed about children’s food intakes and dietary patterns. These are closely linked to children’s appetitive traits (such as disinhibited eating and food fussiness/neophobia). Research has examined both biological and psychosocial correlates or predictors of these traits. There has been less focus on possible processes or mechanisms associated with children’s development of these traits and research that links biological and psychosocial factors. There is an absence of research that links biological and psychosocial factors. In the present article, we outline a model intended to facilitate theory and research on the development of appetitive traits. It is based on scholarship from developmental theory and research and incorporates biological factors such as genetic predispositions and temperament as well as psychosocial factors in terms of parent cognitions, feeding styles and feeding practices. Particular attention is directed to aspects such as emotional eating and feeding, self-regulation of energy intake, and non-shared family environments. We highlight the opportunity for longitudinal research that examines bidirectional, transactional and cascade processes and uses a developmental framework. The model provides a basis for connecting the biological foundations of appetitive traits to system-level analysis in the family. Knowledge generated through the application of the model should lead to more effective prevention and intervention initiatives.Item Body checking induces an attentional bias for body-related cues(John Wiley and Sons, 2011-01) Smeets, Elke; Tiggemann, Marika; Kemps, Eva Bertha; Mills, Jennifer S; Hollitt, Sarah Jane; Roefs, A; Jansen, AObjective: Theoretical models suggest that body checking is linked to biased cognitive processing. However, this link has not been investigated in any systematic way. The present study examined the influence of body checking on attentional bias for body-related cues by manipulating body checking behaviours in non-clinical participants. Method: 66 women were randomly assigned to one of three conditions: body checking, body exposure, or control. A body visual search task was used to measure attentional bias. Results: Participants in the body checking condition showed speeded detection of body-related information compared to participants in the exposure and control conditions. No evidence was found for increased distraction by body-related information. Furthermore, participants in the body checking condition reported more body dissatisfaction after the manipulation than participants in the body exposure and control conditions. Conclusion: These results are the first to experimentally establish the link between body checking and attentional bias toward body-related cues.Item Can attentional bias modification inoculate people to withstand exposure to real-world food cues?(Elsevier, 2017-09-06) Kemps, Eva Bertha; Tiggemann, Marika; Stewart-Davis, EbonyTwo experiments investigated whether attentional bias modification can inoculate people to withstand exposure to real-world appetitive food cues, namely television advertisements for chocolate products. Using a modified dot probe task, undergraduate women were trained to direct their attention toward (attend) or away from (avoid) chocolate pictures. Experiment 1 (N = 178) consisted of one training session; Experiment 2 (N = 161) included 5 weekly sessions. Following training, participants viewed television advertisements of chocolate or control products. They then took part in a so-called taste test as a measure of chocolate consumption. Attentional bias for chocolate was measured before training and after viewing the advertisements, and in Experiment 2 also at 24-h and 1-week follow-up. In Experiment 2, but not Experiment 1, participants in the avoid condition showed a significant reduction in attentional bias for chocolate, regardless of whether they had been exposed to advertisements for chocolate or control products. However, this inoculation effect on attentional bias did not generalise to chocolate intake. Future research involving more extensive attentional re-training may be needed to ascertain whether the inoculation effect on attentional bias can extend to consumption, and thus help people withstand exposure to real-world palatable food cues.Item Can the Theory of Planned Behaviour improve our understanding of the influence of organisational factors on workers’ behaviour?(The Australian Psychological Society, 2007) Freeman, Toby; Roche, Ann Marie; Williamson, Paul; Pidd, Kenneth JohnUnderstanding and changing workers’ behaviour are key goals of Organisational Psychology. The Theory of Planned Behaviour has the potential to make an important contribution to our understanding of how organisational factors influence workers’ behaviour and of ways to achieve behaviour change with workers. According to the Theory of Planned Behaviour, intentions, attitudes, subjective norms, and perceived behavioural control are the most proximal predictors of behaviour. Any distal variables, such as organisational factors, only influence behaviour through the theoretical predictors. Though a substantial body of research has applied the Theory of Planned Behaviour to the organisational setting, no research to-date has examined whether the Theory of Planned Behaviour accounts for the influence of organisational variables on workers’ behaviour. This paper presents the results of a survey of 273 dental hygienists which applied the Theory of Planned Behaviour to the behaviour of assisting their patients to quit smoking. The findings indicated that organisational factors like the presence of a policy and education or training influenced behaviour only through subjective norms and perceived behavioural control. These results inform understanding of the pathways through which organisational factors influence workers’ behaviour. Practical implications of applying the theory to a wide range of work behaviours are highlighted.Item Can We Predict Burnout among Student Nurses? An Exploration of the ICWR-1 Model of Individual Psychological Resilience(Frontiers Media, 2016) Rees, Clare S; Heritage, Brody; Osseiran-Moisson, Rebecca; Chamberlain, Diane Joy; Cusack, Lynette; Anderson, Judith; Terry, Victoria; Rogers, Cath; Hemsworth, David; Cross, Wendy; Hegney, DesleyThe nature of nursing work is demanding and can be stressful. Previous studies have shown a high rate of burnout among employed nurses. Recently, efforts have been made to understand the role of resilience in determining the psychological adjustment of employed nurses. A theoretical model of resilience was proposed recently that includes several constructs identified in the literature related to resilience and to psychological functioning. As nursing students are the future of the nursing workforce it is important to advance our understanding of the determinants of resilience in this population. Student nurses who had completed their final practicum were invited to participate in an online survey measuring the key constructs of the ICWR-1 model. 422 students from across Australia and Canada completed the survey between July 2014 and July 2015. As well as several key demographics, trait negative affect, mindfulness, self-efficacy, coping, resilience, and burnout were measured. We used structural equation modeling and found support for the major pathways of the model; namely that resilience had a significant influence on the relationship between mindfulness, self-efficacy and coping, and psychological adjustment (burnout scores). Furthermore, as predicted, Neuroticism moderated the relationship between coping and burnout. Results are discussed in terms of potential approaches to supporting nursing students who may be at risk of burnout.Item Changes in genetic and environmental influences on disordered eating between early and late adolescence: a longitudinal twin study(Cambridge University Press, 2015-07-02) Fairweather-Schmidt, Kate; Wade, Tracey DianeBackground: We investigated the genetic and environmental contributions to disordered eating (DE) between early and late adolescence in order to determine whether different sources of heritability and environmental risk contributed to these peak times of emergence of eating disorders. Methods: Adolescent female twins from the Australian Twin Registry were interviewed over the telephone with the Eating Disorder Examination (EDE). Data were collected at 12-15 and 16-19 years (Wave 1: N=699, 351 pairs; Wave 3: N=499, 247 pairs). Assessments also involved self-report measures related to negative life events and weight-related peer teasing. Results: Unstandardised estimates from the bivariate Cholesky decomposition model showed both genetic influences and non-shared environmental influences increased over adolescence, but shared environmental influences decreased. While non-shared environmental sources active at ages 12-15 continued to contribute at 16-19 years, new sources of both additive genetic and non-shared environmental risk were introduced at ages 16-19. Weight-related peer teasing in early-mid adolescence predicted increases of DE in later adolescence, while negative life events did not. Conclusions: Two-thirds of the heritable influence contributing to DE in late adolescence was unique to this age group. During late adolescence independent sources of genetic risk, as well as environmental influences are likely to be related in part to peer teasing, appear key antecedents in growth of DE. Key words: Global EDE, adolescents, twins, genetic, environmental, longitudinalItem Childhood maltreatment and the medical morbidity in bipolar disorder: a case–control study(Springer Open, 2017-09-07) Hosang, Georgina; Fisher, Helen L; Uher, Rudolf; Cohen-Woods, Sarah; Maughan, Barbara; McGuffin, Peter W; Farmer, Anne EBackground Childhood maltreatment (abuse and neglect) can have long-term deleterious consequences, including increased risk for medical and psychiatric illnesses, such as bipolar disorder in adulthood. Emerging evidence suggests that a history of childhood maltreatment is linked to the comorbidity between medical illnesses and mood disorders. However, existing studies on bipolar disorder have not yet explored the specific influence of child neglect and have not included comparisons with individuals without mood disorders (controls). This study aimed to extend the existing literature by examining the differential influence of child abuse and child neglect on medical morbidity in a sample of bipolar cases and controls. Methods The study included 72 participants with bipolar disorder and 354 psychiatrically healthy controls (average age of both groups was 48 years), who completed the Childhood Trauma Questionnaire, and were interviewed regarding various medical disorders. Results A history of any type of childhood maltreatment was significantly associated with a diagnosis of any medical illness (adjusted OR = 6.28, 95% confidence intervals 1.70–23.12, p = 0.006) and an increased number of medical illnesses (adjusted OR = 3.77, 95% confidence intervals 1.34–10.57, p = 0.012) among adults with bipolar disorder. Exposure to child abuse was more strongly associated with medical disorders than child neglect. No association between childhood maltreatment and medical morbidity was detected among controls. Conclusions To summarise, individuals with bipolar disorder who reported experiencing maltreatment during childhood, especially abuse, were at increased risk of suffering from medical illnesses and warrant greater clinical attention.Item Chronotype differences in circadian rhythms of temperature, melatonin, and sleepiness as measured in a modified constant routine protocol(Dove Press, 2009) Lack, Leon Colburn; Bailey, Michelle E; Lovato, Nicole; Wright, Helen RuthEvening chronotypes typically have sleep patterns timed 2–3 hours later than morning chronotypes. Ambulatory studies have suggested that differences in the timing of underlying circadian rhythms are a cause of the sleep period differences. However, differences in endogenous circadian rhythms are best explored in laboratory protocols such as the constant routine. We used a 27-hour modified constant routine to measure the endogenous core temperature and melatonin circadian rhythms as well as subjective and objective sleepiness from hourly 15-minute sleep opportunities. Ten (8f) morning type individuals were compared with 12 (8f) evening types. All were young, healthy, good sleepers. The typical sleep onset, arising times, circadian phase markers for temperature and melatonin and objective sleepiness were all 2–3 hours later for the evening types than morning types. However, consistent with past studies the differences for the subjective sleepiness rhythms were much greater (5–9 hours). Therefore, the present study supports the important role of subjective alertness/sleepiness in determining the sleep period differences between morning and evening types and the possible vulnerability of evening types to delayed sleep phase disorder.Item Cigarette cravings impair mock jurors' recall of trial evidence(Taylor & Francis, 2014-11-19) Zuj, Daniel V; Palmer, Matthew Aquinas; Kemps, Eva BerthaPrior research has demonstrated that cravings for substances, such as cigarettes and food, impair performance on basic cognitive tasks. This experiment examined whether these effects translate to impaired cognition on an important task in an applied setting: jury duty. Forty-six smokers were randomly allocated to a high-craving or control condition of an in vivo procedure designed to invoke cigarette cravings. Participants were then asked to act as mock jurors and read a written legal transcript based on evidence presented in an actual civil case. Later, participants were tested on their recall and recognition of information from the transcript. Participants in the high-craving condition recalled fewer correct facts from the transcript than participants in the control condition, but cravings did not significantly affect the recognition of trial information. These results are consistent with cognitive models of cravings, highlight the importance of providing jurors with sufficient breaks, and suggest that cravings may impair cognition in a variety of important applied settings.Item Co-expression network analysis of peripheral blood transcriptome identifies dysregulated protein processing in endoplasmic reticulum and immune response in recurrent MDD in older adults(Elsevier, 2018-10-01) Ciobanu, Liliana G; Sachdev, Perminder; Trollor, Julian N; Reppermund, Simone; Thalamuthu, Anbupalam; Mather, Karen A; Cohen-Woods, Sarah; Stacey, David; Toben, Catherine; Schubert, Klaus Oliver; Baune, Bernhard TThe molecular factors involved in the pathophysiology of major depressive disorder (MDD) remain poorly understood. One approach to examine the molecular basis of MDD is co-expression network analysis, which facilitates the examination of complex interactions between expression levels of individual genes and how they influence biological pathways affected in MDD. Here, we applied an unsupervised gene-network based approach to a prospective experimental design using microarray genome-wide gene expression from the peripheral whole blood of older adults. We utilised the Sydney Memory and Ageing Study (sMAS, N = 521) and the Older Australian Twins Study (OATS, N = 186) as discovery and replication cohorts, respectively. We constructed networks using Weighted Gene Co-expression Network Analysis (WGCNA), and correlated identified modules with four subtypes of depression: single episode, current, recurrent, and lifetime MDD. Four modules of highly co-expressed genes were associated with recurrent MDD (N = 27) in our discovery cohort (FDR<0.2), with no significant findings for a single episode, current or lifetime MDD. Functional characterisation of these modules revealed a complex interplay between dysregulated protein processing in the endoplasmic reticulum (ER), and innate and adaptive immune response signalling, with possible involvement of pathogen-related pathways. We were underpowered to replicate findings at the network level in an independent cohort (OATS), however; we found a significant overlap for 9 individual genes with similar co-expression and dysregulation patterns associated with recurrent MDD in both cohorts. Overall, our findings support other reports on dysregulated immune response and protein processing in the ER in MDD and provide novel insights into the pathophysiology of depression.