Effects of Complexity on Visuo-spatial Working Memory

Author version made available in accordance with the publisher's policy.Four experiments are reported in which the effect of complexity on short-term retention of visuo-spatial material was explored. The determinants of complexity can be separated into a quantitative factor, which sets an upper bound on complexity, and a structural factor, which reduces complexity. Variants of the Corsi blocks task were administered across the various experiments. Quantitative complexity was manipulated through the number of blocks on the board. Structural complexity was induced through the positioning of the blocks. Visuo-spatial span was found to be susceptible to both measures of complexity. Performance was inversely related to the number of blocks. Recall was also better when the blocks were positioned in a matrix than in a random fashion. Moreover, the effect of complexity was shown to be moderated by an interaction between structure and amount of information presented. These results demonstrate that complexity is an important characteristic of visuo-spatial working memory. This phenomenon may be used to further explore the properties of the visuo-spatial sketch pad, and advance its theoretical development

Complexity effects in visuo-spatial working memory: Implications for the role of long-term memory

Author version made available in accordance with the publisher's policy.Several studies have shown that the capacity of visuo-spatial working memory is limited by complexity. Using a variant of the Corsi blocks task, this paper investigated the effect of complexity of the to-be-remembered path on visuo-spatial memory span. Redundancy was determined by three Gestalt principles: symmetry, repetition and continuation. Experiment 1 revealed an effect of path complexity. The subsequent experiments explored whether the superiority for recall of structured over complex paths can be attributed solely to the operation of visuo-spatial working memory, or whether it also reflects the use of long-term knowledge. Experiment 2 demonstrated that the effect of complexity remained, even when the mechanisms for visuo-spatial coding were removed by a secondary visuo-spatial task. In Experiments 3 and 4 subjects were trained in the recall of complex paths. This led to the creation of long-term memory representations for these paths, as shown by an improvement in their span, and a concomitant lack of transfer to new paths. Finally, Experiment 5 showed that one prior repetition of a complex path was sufficient to produce specific and long-term learning effects. These results point to the involvement of long-term memory processes in the temporary retention of visuo-spatial material for which representations exist in long-term memory. They also suggest that the effect of complexity may provide a tractable technique for investigating the mechanisms underlying the limits of visuo-spatial short-term storage

Approach bias for food cues in obese individuals

This 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

Olfactory stimulation curbs food cravings

Author version made available in accordance with the publisher's policy for non-mandated open access submission. Under Elsevier's copyright, non-mandated authors are permitted to make work available in an institutional repository.Based on the logic of mutual competition between cravings and odours for limited-capacity resources, this study investigated whether a simple olfactory task, involving a brief odour exposure, could reduce food cravings. In support, Experiment 1 showed that smelling a neutral unfamiliar odorant reduced cravings for highly desired food items, relative to a comparison auditory task and a no-task control condition. Experiment 2 replicated these findings specifically for chocolate cravings, which can be particularly problematic. Thus olfactory stimulation offers potential scope for curbing unwanted food cravings. Keywords: craving; food; odour; craving reductio

Hand-held dynamic visual noise reduces naturally occurring food cravings and craving-related consumption

Author version made available in accordance with the publisher's policy for non-mandated open access submission. Under Elsevier's copyright, non-mandated authors are permitted to make work available in an institutional repository.This study demonstrated the applicability of the well-established laboratory task, dynamic visual noise, as a technique for reducing naturally occurring food cravings and subsequent food intake. Dynamic visual noise was delivered on a hand-held computer device. Its effects were assessed within the context of a diary study. Over a 4-week period, 48 undergraduate women recorded their food cravings and consumption. Following a 2-week baseline, half the participants watched the dynamic visual noise display whenever they experienced a food craving. Compared to a control group, these participants reported less intense cravings. They were also less likely to eat following a craving and consequently consumed fewer total calories following craving. These findings hold promise for curbing unwanted food cravings and craving-driven consumption in real-world settings

A Cognitive Experimental Approach to Understanding and Reducing Food Cravings

Author version made available in accordance with the publisher's policy.Food cravings are a common everyday experience. Yet, they can pose significant health risks for some people. Following initial investigations into the phenomenology, antecedents and consequences of food cravings, recent scientific interest has turned to the underpinnings of the actual craving experience itself. In this article, we outline a conceptual framework for studying food cravings that is grounded in cognitive experimental psychology, along with our corresponding program of research. In particular, we present converging evidence from a number of seemingly disparate lines of research into the cognitive processes that underlie food cravings with a view to developing a craving-reduction technique

External eating mediates the relationship between impulsivity and unhealthy food intake

Recent evidence from the eating domain shows a link between impulsivity and unhealthy food intake. However, the mechanism underlying this relationship remains unclear. One possibility is an external eating style, which has been linked to both impulsivity and food intake. The current study investigated the potential mediating role of external eating in the relationship between impulsivity and food intake. Participants were 146 undergraduate women who completed measures of impulsivity and external eating, and took part in a laboratory taste test as a behavioural index of unhealthy snack food intake. It was found that attentional and motor impulsivity interacted in predicting sweet food intake, but only motor impulsivity predicted both external eating and sweet food intake. Furthermore, the relationship between motor impulsivity and food intake was mediated by external eating. These findings support the development of interventions aimed at targeting specific aspects of impulsivity in order to reduce unhealthy eating behaviour.This research was supported under the Australian Research Council's Discovery Project funding scheme (project number DP130103092)

Sustained effects of attentional re-training on chocolate consumption

Background and objectives Accumulating evidence shows that cognitive bias modification produces immediate changes in attentional bias for, and consumption of, rewarding substances including food. This study examined the longevity of these attentional bias modification effects. Methods A modified dot probe paradigm was used to determine whether alterations in biased attentional processing of food cues, and subsequent effects on consumption, were maintained at 24-h and one-week follow-up. One hundred and forty-nine undergraduate women were trained to direct their attention toward (‘attend’) or away from (‘avoid’) food cues (i.e., pictures of chocolate). Within each group, half received a single training session, the other half completed 5 weekly training sessions. Results Attentional bias for chocolate cues increased in the ‘attend’ group, and decreased in the ‘avoid’ group immediately post training. Participants in the ‘avoid’ group also ate disproportionately less of a chocolate food product in a so-called taste test than did those in the ‘attend’ group. Importantly, the observed re-training effects were maintained 24 h later and also one week later, but only following multiple training sessions. Limitations There are a number of limitations that could be addressed in future research: (a) the inclusion of a no-training control group, (b) the inclusion of a suspicion probe to detect awareness of the purpose of the taste test, and (c) the use of different tasks to assess and re-train attentional bias. Conclusions The results showed sustained effects of attentional re-training on attentional bias and consumption. They further demonstrate the importance of administering multiple re-training sessions in attentional bias modification protocols.This research was supported under the Australian Research Council's Discovery Project funding scheme (project number DP130103092)

The affective primacy hypothesis: Affective or cognitive processing of optimally and suboptimally presented primes?

Copyright 1996 Psychologica Belgica. Author version of the paper reproduced here with permission from the publisher.The 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

Attentional bias modification encourages healthy eating

This article appeared in a journal published by Elsevier Ltd. Under Elsevier's copyright, mandated authors are not permitted to make work available in an institutional repository.The 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