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  • Relative validity effects with either one or two more valid cues in Pavlovian and instrumental conditioning.

    7 March 2018

    Two experiments investigated the relative validity effect with either 1 or 2 continuously reinforced cues in Wistar rats using appetitive Pavlovian and instrumental preparations. Discrimination training involved 3 compound cues containing a common element (1AX: 1BX: 2CX). In the first true-discrimination group (TD-1), CX was followed by food, but AX and BX were not. In the second true-discrimination group (TD-2), AX and BX but not CX were followed by food. In the third, pseudodiscrimination group (PD), food followed 50% of each compound. Compared with the PD group, there were lower levels of responding to X in Groups TD-1 and TD-2, which did not differ. That is, both TD treatments showed equivalent relative validity effects. There was evidence for a relative validity effect on the context. The Rescorla-Wagner model incorrectly predicts a smaller relative validity effect after the TD-2 than the TD-1 treatment. Comparator theory predicts these results.

  • Rule learning by rats.

    28 January 2018

    Using rules extracted from experience to solve problems in novel situations involves cognitions such as analogical reasoning and language learning and is considered a keystone of humans' unique abilities. Nonprimates, it has been argued, lack such rule transfer. We report that Rattus norvegicus can learn simple rules and apply them to new situations. Rats learned that sequences of stimuli consistent with a rule (such as XYX) were different from other sequences (such as XXY or YXX). When novel stimuli were used to construct sequences that did or did not obey the previously learned rule, rats transferred their learning. Therefore, rats, like humans, can transfer structural knowledge from sequential experiences.

  • Negative Interpretation Bias and the Experience of Pain in Adolescents.

    28 January 2018

    UNLABELLED: Negative interpretation bias, the tendency to appraise ambiguous situations in a negative or threatening way, has been suggested to be important for the development of adult chronic pain. To our knowledge, this is the first study to examine the role of a negative interpretation bias in adolescent pain. We first developed and piloted a novel task that measures the tendency for adolescents to interpret ambiguous situations as indicative of pain and bodily threat. Using this task in a separate community sample of adolescents (N = 115), we then found that adolescents who catastrophize about pain, as well as those who reported more pain issues in the preceding 3 months, were more likely to endorse negative interpretations, and less likely to endorse benign interpretations, of ambiguous situations. This interpretation pattern was not, however, specific for situations regarding pain and bodily threat, but generalized across social situations as well. We also found that a negative interpretation bias, specifically in ambiguous situations that could indicate pain and bodily threat, mediated the association between pain catastrophizing and recent pain experiences. Findings may support one potential cognitive mechanism explaining why adolescents who catastrophize about pain often report more pain. PERSPECTIVE: This article presents a new adolescent measure of interpretation bias. We found that the tendency to interpret ambiguous situations as indicative of pain and bodily threat may be one potential cognitive mechanism explaining why adolescents who catastrophize about pain report more pain, thus indicating a potential novel intervention target.

  • Reply to Falcon.

    28 January 2018

  • Resource allocation and prioritization in auditory working memory.

    12 March 2018

    A prevalent view of working memory (WM) considers it to be capacity-limited, fixed to a set number of items. However, recent shared resource models of WM have challenged this “quantized” account using measures of recall precision. Although this conceptual framework can account for several features of visual WM, it remains to be established whether it also applies to auditory WM. We used a novel pitch-matching paradigm to probe participants' memory of pure tones in sequences of varying length, and measured their precision of recall. Crucially, this provides an index of the variability of memory representation around its true value, rather than a binary "yes/no" recall measure typically used in change detection paradigms. We show that precision of auditory WM varies with both memory load and serial order. Moreover, auditory WM resources can be prioritized to cued items, improving precision of recall, but with a concomitant cost to other items, consistent with a resource model account.

  • Motor phenotype and magnetic resonance measures of basal ganglia iron levels in Parkinson's disease.

    20 March 2018

    BACKGROUND: In Parkinson's disease the degree of motor impairment can be classified with respect to tremor dominant and akinetic rigid features. While tremor dominance and akinetic rigidity might represent two ends of a continuum rather than discrete entities, it would be important to have non-invasive markers of any biological differences between them in vivo, to assess disease trajectories and response to treatment, as well as providing insights into the underlying mechanisms contributing to heterogeneity within the Parkinson's disease population. METHODS: Here, we used magnetic resonance imaging to examine whether Parkinson's disease patients exhibit structural changes within the basal ganglia that might relate to motor phenotype. Specifically, we examined volumes of basal ganglia regions, as well as transverse relaxation rate (a putative marker of iron load) and magnetization transfer saturation (considered to index structural integrity) within these regions in 40 individuals. RESULTS: We found decreased volume and reduced magnetization transfer within the substantia nigra in Parkinson's disease patients compared to healthy controls. Importantly, there was a positive correlation between tremulous motor phenotype and transverse relaxation rate (reflecting iron load) within the putamen, caudate and thalamus. CONCLUSIONS: Our findings suggest that akinetic rigid and tremor dominant symptoms of Parkinson's disease might be differentiated on the basis of the transverse relaxation rate within specific basal ganglia structures. Moreover, they suggest that iron load within the basal ganglia makes an important contribution to motor phenotype, a key prognostic indicator of disease progression in Parkinson's disease.

  • At the edge of consciousness: automatic motor activation and voluntary control.

    6 March 2018

    Conventionally, voluntary conscious acts and automatic behavior have been considered to be mediated by separate processes-and by separate brain structures. In this review, the authors consider the evidence that this might not be the case. First, they draw together disparate lines of evidence showing that visual stimuli cause automatic and unconscious motor activation. They briefly discuss the visual grasp reflex (automatic orienting of gaze to a salient visual stimulus), subliminal priming, and object affordances in healthy individuals. They also consider cases where inhibition of such reflexive behavior may be disrupted following brain lesions, as in patients demonstrating alien limb syndrome and utilization behavior. The authors argue that automatic motor activation forms an intrinsic part of all behavior, rather than being categorically different from voluntary actions. A crucial issue is how such automatic mechanisms are controlled so that the most appropriate responses are made and unwanted responses inhibited. The authors discuss some of the brain areas involved, including the supplementary motor area and the parietal cortex. Last, they review evidence that some control may actually be achieved by automatically triggered inhibition as well as modulation of unconscious processes by attention and task goals.

  • Short test of semantic and phonological fluency: normal performance, validity and test-retest reliability.

    6 February 2018

    Tests of verbal fluency, whether of Semantic Fluency (SF) or Phonological Fluency (PF), are often used as a standard method of neuropsychological assessment. However, very little normative data, standardized on a UK sample, is available, and little is known about the utility of popularly used 'short-forms' of these tasks. Additionally, very little is known about verbal fluency test-retest reliability. In this report we describe the performance of N = 365 normal participants on a version of SF requiring the generation of exemplars of the category 'animals' and a version of the PF task requiring participants to generate words beginning with the letter 'B'. From this data we have derived a percentile distribution for both tasks. We also addressed the impact of sex, age, years of education and IQ upon both SF and PF performance. No sex differences were found on either the PF or the SF tasks. A significant but small correlation between age and SF, but not PF, was observed. Modest correlations between both years of education and IQ and PF and SF performance were also seen. We also report test-retest reliability scores for performance on both SF and PF tasks. Performance on the longer 'FAS' version was found to correlate highly with scores obtained using just the letter 'B'. This suggests that little additional advantage obtains from administering three-letter versions of PF. An extremely high degree of correlation between SF tasks in which participants are given 1 minute and scores obtained when participants are given 1 minute 30 seconds was also observed. Finally, in order to assist users in deciding whether a changed retest score is due to error measurement or a real effect, we calculated Standard Error of Prediction (SEP) scores.

  • Positive and negative asymmetry of intergroup contact: A dynamic approach

    21 December 2015

    Whilst intergroup contact can be positive (e.g., having outgroup friends) it can also be negative (e.g., being bullied by an ethnic outgroup member). Diverse settings (e.g., schools, neighbourhoods) could potentially have unintended consequences of actually increasing prejudice because they may expose people to greater frequency of both positive and negative contact (which may undermine positive effects of contact). This project asks: What is the net effect on outgroup attitudes of a mix of both positive and negative contact; how and when do such effects arise dyadically, in social networks, and at the context-level; and what possible consequences might result from their interplay? Preliminary correlational evidence indicates that negative contact has stronger effects on attitudes than positive contact does (although positive contact is more common); we refer to this effect as a Positive-Negative Asymmetry of Contact (PNAC) effect. The broad objectives of the research are to explore the independent and combined consequences of positive and negative contact at interpersonal, network, and context levels, integrating both social-psychological and sociological approaches. We focus on dynamic effects to provide insights into the short- and long-term consequences of having both positive and negative contact with diverse outgroup members. We use a mixed-methods approach complementing laboratory experiments with a diary study, longitudinal surveys, and social networks surveys, using sample populations from three different countries. This allows us to exploit the strengths of different approaches in terms of internal and external validity, and to increase the generalizability of our results. We will also evaluate the dynamic interplay of positive and negative contact in a large-scale social intervention aimed at improving intergroup relations. The proposed research has 5 main aims, using various theoretical and methodological perspectives, spanning sociology and social psychology, and encompassing a variety of research designs: 1. To assess the extent to which negative contact effects threaten the efficacy of positive contact to reduce prejudice, across multiple paradigms (experiments, social networks, longitudinal surveys, intervention-evaluation). 2. To investigate dynamic PNAC effects over time. 3. To test whether PNAC effects are mediated by category salience and moderated by intensity, consistency, order of valenced contact, and majority-minority status. 4. To investigate evidence for buffering, augmentation and poisoning effects at interpersonal-, network- and context-levels. 5. To simultaneously examine the interdependent formation and dynamics of positive and negative contact by testing (a) how positive contact influences negative contact and vice versa and (b) how positive and negative contact influence attitudes.

  • Making Words Stick: Lexical Consolidation Effects in Learning to Read

    24 July 2015

    To become skilled readers, children need to move from sounding words out to recognising them rapidly via access to rich, long-term memory representations. Little is known about how this transition is achieved, and why some children have difficulty. This project will address these questions in a set of learning studies with typically-developing and reading-impaired children, focussing particularly on the long-term consolidation of word representations. We will explore the role of sleep in promoting the consolidation process, in both children and adults. The findings will directly inform theory and practice in reading acquisition and enhance the treatment of reading difficulties.

  • Nurturing a Lexical Legacy: Understanding the Transition From Novice-to-Expert in Children's reading Development

    24 July 2015

    How do children move from slow and effortful reading, where they "sound-out" words and struggle with fluency, to develop the fast, efficient and effective word recognition system that characterises skilled visual word recognition? Our new programme of research, funded by the Economic and Social Research Council, will help us answer this question.

  • Eye Movements and Literary Reading

    24 July 2015

    This project explores the utility of eye-tracking in the study of literary devices characteristic of both Modernist literature and the popular crime/thriller genre. Experimenters typically use simple texts of only a sentence or two rather than real literary texts. Our studies will increase scientific understanding of how authentic literary texts are read, as well as demonstrate the value of complementing theoretical claims about literary devices with empirical testing.

  • Archive

    30 September 2015

    Presentations given by members of the Project Team at earlier stages of the Wellcome Language and Reading Project

  • Useful resources

    30 September 2015

    Project newsletters and updates

  • Case studies

    30 September 2015

    Two cases studies featuring children involved in the project

  • Project overview

    30 September 2015

  • Research Impact

    23 August 2017

    The societal and economic impact of medical research is fast becoming an integral part of research assessment. Here you can explore some of the recent impact case studies from Experimental Psychology researchers.