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The receptive field (RF) is the fundamental processing unit of human vision; both masking and crowding depend on its size. The RF has a psychophysical corresponding term, the perceptive field (PF); whereas the RF is measured physiologically, the PF is measured psychophysically (a perceptual response). We investigated how spatial (lateral interactions), temporal (the stimulus presentation time), and the procedure affect the PF size for both monocular and binocular viewing. The stimuli consisted of a central vertically oriented Gabor target and high-contrast Gabor flankers positioned in two configurations (orthogonal or collinear) with target-flanker separations of either 2 or 3 wavelengths (λ). We used two main methods to control the monocular and binocular vision: mono-optic glasses vs. stereo glasses. The presentation order was either mixed or non-mixed for the presentation time and the eye condition. We estimated the PF size for both monocular and binocular viewing at 4 different presentation times (40, 80,120, and 200 ms) with different orders of presentation in each experiment (mono-optic glasses vs. stereo glasses, utilizing the lateral masking paradigm). In each experiment we explored one variable: how changing one parameter would affect the PF size in both monocular and binocular viewing (the temporal duration, the testing order of conditions, and the spatial distance) while keeping the others constant. We found that both the monocular and binocular PF size were dynamic and were significantly affected by the presentation order, leading to reduced lateral suppression under the collinear 2λ condition. Hence, both the monocular and binocular PF size depended on the sequence of the stimulus presentation time and the testing order of the conditions. Furthermore, we found that the binocular PF size was significantly larger than the monocular PF size. [ABSTRACT FROM AUTHOR]

Previous studies have found that inhibitory control plays an important role in non-symbolic numerical processing. However, this role may be influenced by the visual cue control method or the stimulus' presentation time. We investigated these questions by conducting three experiments using a priming paradigm to compare the level of inhibitory control in a sequential dot comparison task with single-dimensional and multi-dimensional control of visual cues under two presentation time conditions (300 ms and 1500 ms). We found that neither the method of visual cue control nor the presentation time of dot arrays affected the level of inhibitory control in the dot comparison task. These results reveal a stable role of inhibitory control in non-symbolic numerical processing, providing further evidence for integrating numerical and visual information during non-symbolic numerical processing. • The visual cue control method does not affect the role of inhibitory control. • The dot presentation time does not affect the role of inhibitory control. • Inhibitory control remains relatively stable in non-symbolic numerical processing. [ABSTRACT FROM AUTHOR]

Objective: Greater time that patients take to present symptoms to health care providers (HCPs) increases the likelihood of later stage cancer, which increases mortality and morbidity in symptomatic cancers. The common-sense model (CSM) is used to understand time to first consultation with a healthcare provider, but inconsistencies exisy between its current use and important empirical findings.Method: To resolve inconsistencies, we conducted a qualitative examination to determine how the CSM could be revised to better account for these findings. We conducted in-depth interviews of a consecutive sample of 38 recently diagnosed patients who described events from first noticing symptoms to first consultation. Framework analysis was used to develop a theoretical model of processes leading to presentation or non-presentation.Results: Patients reported median presentation times of 3-4 weeks. Early presentation was facilitated by pre-symptomatic perceptions of vulnerability to serious illnesses and beliefs that early intervention could mitigate illness. These patients rarely tried to identify symptoms. They responded inductively, seeking help because symptoms were unusual. Where patients did not describe pre-symptom perceptions of vulnerability, many deductively tried to identify symptoms but misattributed them to minor conditions. Pre-symptomatic perceptions of vulnerability could also prolong presentation. When vulnerability was characterized by intense fears of cancer and cancer treatment, patients tended to avoid thinking about symptoms which extended presentation time.Conclusion: Risk perception theories explain how participants' pre-symptomatic perceptions of vulnerability and potential treatment outcomes influence presentation time. Incorporating risk perception perspectives into the CSM can improve its ability explain responses to ambiguous symptoms. [ABSTRACT FROM AUTHOR]

Background A number of studies have investigated the effect of presentation time on the outcome of patients presenting following trauma. However, it is uncertain whether there is a difference in the incidence of missed injuries between patients presenting during ‘office hours’ to those presenting in the ‘after-hours’ period. Materials and methods We analysed all patients recorded in the Trauma Registry of Royal Perth Hospital (a Level I Trauma Centre for adults in Western Australia) between 2003 and 2013. Patients were divided into 3 groups i.e. those presenting during office hours, those presenting ‘after-hours’ on a weekday and those presenting on a weekend. In 2008, the State Major Trauma Unit (SMTU) at RPH was initiated following which in-hospital cover by the Trauma Fellows was extended to 11 PM on weekdays. The study was therefore divided into two time periods i.e. pre-SMTU (2003–2007) and post-SMTU (2008–2013). Results 53,030 patients were recorded in the Trauma Registry in the 10-year period (major and minor trauma). There were 2519 missed injuries in 1262 patients (2.4%). Of these, 2.2% patients presented during office hours, 2.6% ‘after-hours on a weekday’ and 2.5% on weekends. The odds of missing an injury were 1.2 times higher if the patient presented after-hours ( p = 0.048). Missed injury rates were found to have increased over the past 10 years ( p = 0.0179). The odds of missing an injury in 2013 were 1.34 times higher than in 2003. Most of the missed injuries were AIS 1 and 2 (19.8 and 59%) and 55% had no clinical impact on the patients. Thoracic Spine and abdominal injuries were most commonly missed. The only region to show a significant difference between the 3 groups of patients studied was the abdomen (5.3% vs 11.1% vs 6.3%; p = 0.004). It was also seen that a larger number of hollow viscus abdominal injuries (5.2%) were missed when compared to solid organs (3.2%; p < 0.001). Conclusion Injuries in patients sustaining trauma are more likely to be missed ‘after-hours’ than during ‘office hours’. T-spine and abdominal injuries are more likely to be missed when compared to other anatomical regions of the body. [ABSTRACT FROM AUTHOR]

Abstract: A leftward spatial bias has been observed with visuospatial attention tasks, including line bisection and the greyscales task. Upper and lower visual field differences have been observed on various tasks, with a lower visual field advantage occurring for motion, global processing and coordinate spatial judgments. Upper visual field advantages occur for visual search, local processing and categorical judgments. In perceptual asymmetries research, upper and lower visual field differences have not typically been scored separately, as most presentations have been central. Mixed results have made it difficult to determine whether lateral biases are stronger in the upper or the lower visual field. As length of presentation time differed in prior studies, this factor was examined to determine whether it would lead differential biases to emerge in each visual field. The greyscales task was used to investigate the interaction of visual field and presentation time within subjects (N =43). Eye tracking was used during the task and supported the hypothesis of a stronger left bias in the lower visual field. Presentation time and visual field interacted to influence performance. Prolonged presentation led to a stronger leftward bias in the lower visual field whereas the leftward bias was stronger in the upper visual field during brief presentation. Results showed a relation between the lower and left visual fields and the upper and right visual fields, which has not previously been shown in perceptual asymmetries. Further, it is suggested that functional differences between the visual streams could underlie the visual field differences in perceptual asymmetries. [Copyright &y& Elsevier]

Abstract: Functional magnetic resonance imaging (fMRI) was used in 14 healthy subjects to measure brain activation, while response shifting was performed. In the activation phase, subjects were asked to shift their attention between two different types of visually presented stimuli. In the baseline phase, subjects were required to attend to one stimulus type only. Subjects responded by pressing a left or right key according to the side of presentation of the target stimuli. In a verbal task, subjects were required to switch between letters and numbers. In a figural task, subjects reacted to round and square shapes. Stimuli were presented for 750 or 1500 ms. Response shifting revealed significantly increased activation compared to non-switching in the bilateral superior parietal cortex, right occipital cortex, left inferior frontal cortex, left and right striatum, and bilateral dorsolateral prefrontal cortex (DLPFC). Superior parietal and occipital cortex activation may be due to spatial analysis during response shifting. Subvocal rehearsal of the task instructions may have led to activation in the left inferior frontal cortex. Activation in the striatum was related to prefrontal activation and may represent the association between basal ganglia and prefrontal activation during executive control. However, the most important brain region involved in the execution of response shifting was the bilateral DLPFC. Higher task speed increased executive top–down attentional control and, therefore, significantly increased activity in the bilateral DLPFC. Brain activation did not differ significantly between verbal and figural stimulus material. This result suggests that brain activation in the present study illustrates the brain regions involved in the basic cognitive mechanisms of response shifting. [Copyright &y& Elsevier]