Visual search in the real world: evidence for the formation of distractor representations

Visual search in the real world often requires that we search the same environment a number of times for different targets. What is the fate of information about fixated distractor objects during these searches? Here, participants searched the same array of real objects on a tabletop twice for two different targets successively whilst wearing a head-mounted eye-tracker. We found that fixating an object when it was a distractor in the first search facilitated search for that same object when it became the target in the second search. The results suggest that the location and identity of fixated distractor objects are represented to a level that guides subsequent searches, even when this information is not required at the time of fixation.     

Infant cognition: going full factorial with pupil dilation

The violation‐of‐expectation (VOE) paradigm and related methods are the main tools used to study high‐level cognition in preverbal infants. Infants’ differential looking to conceptually implausible/impossible events has been used as an index of early cognitive competence in many areas, including object knowledge, physics, language, and number. However, an event's plausibility is commonly confounded with its perceptual novelty or familiarity, leading to a variety of interpretations for looking time data ( Bogartz, Shinskey & Speaker, 1997 ). This illustrative study demonstrates the value of factorial designs, in which perceptual (novelty–familiarity) and conceptual (possible–impossible) variables are independently and jointly explored. It also introduces pupil dilation as a viable and complementary dependent measure to study infant cognition. We show that pupil data can assist in the interpretation of otherwise equivocal looking time data. The discussion focuses on methodological considerations in infancy research.     

The mechanism underlying inhibition of saccadic return

Human observers take longer to re-direct gaze to a previously fixated location. Although there has been some exploration of the characteristics of inhibition of saccadic return (ISR), the exact mechanisms by which ISR operates are currently unknown. In the framework of accumulation models of response times, in which evidence is integrated over time to a response threshold, ISR could reflect a reduction in the rate of accumulation for saccades to return locations or an increase in the effective criterion for response. In two experiments, participants generated sequences of three saccades, in response to a peripheral or a central cue. ISR occurred across these manipulations: saccade latency was consistently increased for movements to the immediately previously fixated location. Latency distributions from individual observers were fit with a Linear Ballistic Accumulator model. ISR was best accounted for as a change in the accumulation rate. We suggest this parameter represents the overall desirability of a particular course of action, the evidence for which may be derived from a variety of sensory and non-sensory sources.     

Body Composition And Human Sleep

It has been reported that fit atheletes have more slow wave sleep (SWS), sleep longer and have shorter sleep onset latencies than unfit individuals. However, we have shown that these differences are not a direct consequence of physical fitness. This suggests that the effect is due to more enduring characteristics of individuals. We report two experiments designed to test the hypothesis that individual differences in sleep are related to differences in body composition. The hypothesis was tested in two different experiments, each comparing independent groups of fit athletes with unfit non-athletes. In each experiment both sleep and a number of anthropometric variables were measured. Twenty-five fit and 22 unfit subjects were run in Experiment 1 and 17 fit and 17 unfit in Experiment 2. In Experiment 1 percentage fat was estimated from a skin fold method, while in Experiment 2 lean body mass (LBM) was estimated from 24 h. urinary creatinine. The results showed that percentage LBM was negatively related to SWS in fit subjects, while the amount of LBM and weight were negatively related in the unfit groups. When all subjects were combined within each experiment, significant negative correlations were found between SWS and both LBM and percentage LBM in Experiment 2. The results suggest that body composition influences SWS levels, but not other components of sleep.     

The relationship between collective efficacy and precompetitive affect in rugby players: testing Bandura's model of collective efficacy

This study extended research examining Bandura's (1997) proposed model of collective efficacy. Specifically, it examined the relationships between groups' collective efficacy and the precompetitive anxiety and affect they experienced. Prior to a competitive match 66 male Rugby Union footballers from 6 teams (2 university teams and 4 county league teams) completed a single-item measure of confidence in their team winning the forthcoming match, a 10-item measure of confidence in their team performing well in the forthcoming match, the modified Competitive State Anxiety Inventory-2, and the Positive and Negative Affect Schedule. Stepwise (forward) multiple regression analyses indicated that scores for collective efficacy accounted for only 6.3% of the variance in the intensities of cognitive state anxiety and only 22% of the variance in the positive affect experienced prior to the rugby match. The results indicate that concerns with the team's ability to win a match were associated with high cognitive state anxiety and that doubts regarding the team's ability to perform well were related to low positive affect. Given the magnitude of predicted variances, the findings seem to give some support to Bandura's proposal that the beliefs in collective efficacy of individuals engaged in a team task are related to precompetitive affective reactions and the experience of state anxiety.     

The influence of cognitive load on spatial search performance

During search, executive function enables individuals to direct attention to potential targets, remember locations visited, and inhibit distracting information. In the present study, we investigated these executive processes in large-scale search. In our tasks, participants searched a room containing an array of illuminated locations embedded in the floor. The participants’ task was to press the switches at the illuminated locations on the floor so as to locate a target that changed color when pressed. The perceptual salience of the search locations was manipulated by having some locations flashing and some static. Participants were more likely to search at flashing locations, even when they were explicitly informed that the target was equally likely to be at any location. In large-scale search, attention was captured by the perceptual salience of the flashing lights, leading to a bias to explore these targets. Despite this failure of inhibition, participants were able to restrict returns to previously visited locations, a measure of spatial memory performance. Participants were more able to inhibit exploration to flashing locations when they were not required to remember which locations had previously been visited. A concurrent digit-span memory task further disrupted inhibition during search, as did a concurrent auditory attention task. These experiments extend a load theory of attention to large-scale search, which relies on egocentric representations of space. High cognitive load on working memory leads to increased distractor interference, providing evidence for distinct roles for the executive subprocesses of memory and inhibition during large-scale search.     

Self and peer nominations of bullying: An analysis of incident rates,individual differences,and perceptions of the working environment

Within workplace bullying research, the use of different criteria to identify victim samples, and a tendency to rely on self-reported victimization without including reports from other stakeholders have been considered major methodological problems associated with incidence studies (Cowie, Naylor, Rivers, Smith, & Pereira, 2002; Hoel, Rayner, & Cooper, 1999; Randall, 2001). Using diverse criteria to identify victim and perpetrator samples (such as self report, peer report, and self- and peer report), this study found rates of victimization and bullying varied quite considerably. Rates for victims ranged from 3.9% to 39.6% and for perpetrators from 2.7% to 19.3%. Differences in personality and perceptions of the organizational environment were then examined between victim/bully groups and a control sample. Results indicated that all victim samples differed significantly from controls on stability. However, self- and peer-reported victims differed significantly from controls on both the poised and relaxed subscales, whereas self-reported victims only differed significantly on the relaxed subscale. Additionally, self- and peer-reported victims were the only group that significantly differed from controls in their views of the negative aspects of the work environment. The notion that victim and perpetrator samples are not homogenous groups and considerations of why this is the case are discussed.