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Binocular vision may serve as a good model for research on awareness. Binocular summation (BS) can be defined as the superiority of binocular over monocular visual performance. Early studies of BS found an improvement of a factor of about 1.4 (empirically), leading to models suggesting a quadratic summation of the two monocular inputs (√2). Neural interaction modulates a target's visibility within the same eye or between eyes (facilitation or suppression). Recent results indicated that at a closely flanked stimulus, BS is characterized by instability; it relies on the specific order in which the stimulus condition is displayed. Otherwise, BS is stable. These results were revealed in experiments where the tested eye was open, whereas the other eye was occluded (mono-optic glasses, blocked presentation); thus, the participants were aware of the tested eye. Therefore, in this study, we repeated the same experiments but utilized stereoscopic glasses (intermixed at random presentation) to control the monocular and binocular vision, thus potentially eliminating awareness of the tested condition. 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 two or three wavelengths (λ), presented at four different presentation times (40, 80, 120, and 200 ms). The results indicate that when utilizing stereoscopic glasses and mixing the testing conditions, the BS is normal, raising the possibility that awareness may be involved. [ABSTRACT FROM AUTHOR]

According to the attentional boost effect (ABE), detecting a target in a dual-task paradigm can facilitate memory encoding of concurrently presented stimuli, but the detection stimuli always appears transiently (only for 100 ms). In order to gain deeper insights into the mechanisms behind ABE, it is crucial to investigate whether the brief presentation of the detection stimulus is a necessary prerequisite for generating ABE. To address this issue, the present study manipulated the presentation time of the detection stimulus (500-ms vs. 100 ms) and controlled the study-testing time interval (immediate test vs. 24 h test). It turned out that, the short-duration (100 ms) detection condition produced an ABE similar to that of the long-duration (500 ms) condition at the immediate test, but only the ABE produced by the short-duration condition could be continued until the 24 h test (Experiments 1), and the ABE produced by the long-duration condition disappeared in the 24 h test. Nonetheless, when a retrieval practice session was introduced before the 24 h test, the ABE generated by the long-duration condition also extended to the 24 h test (Experiment 2). Regarding ERP components, the short-duration detection condition elicited a more negative mean amplitude in the 500–700 ms time window compared to the long detection-duration condition (Experiment 3). This implies that the duration of the detection stimulus likely plays a central role in influencing ABE through its effect on engram stability, with the short-duration condition potentially leading to a more stable engram compared to the long-duration condition. [ABSTRACT FROM AUTHOR]

Abstract Purpose The few studies that have explored self-harm presentation times at hospital emergency departments (EDs) – an important factor that can determine if a patient receives a mental health assessment – primarily focus on adult samples. This study examined the times of self-harm presentations to EDs, self-harm methods used, mental health assessments, and admission data across different age-groups. Methods Using data from the National Self-Harm Registry Ireland over a 13-year timeframe (2007–2019), this study compared times, days, seasons, methods of self-harm, and admission data for children (8–12 years), adolescents (13–17 years), young adults (18–25 years) and adults (> 25 years). Results The majority of the 152,474 self-harm presentations (78.6%) for all ages occurred out-of-hours (outside the standard working hours or in-hours times of 09:00–17:00, Monday-Friday). The four hours before midnight had the highest proportions of self-harm presentations for adolescents (27.9%) and adults (23.1%), whereas the four hours after midnight had the highest proportion of self-harm presentations for young adults (22.9%). The 16:00-midnight timeframe had highest proportion of self-harm presentations in children (52.3%). Higher proportions of patients received a mental health assessment in-hours compared to out-of-hours among young adults (78.2% vs. 73.3%) and adults (76.1% vs. 72.0%). Self-harm presentations were lowest during summer months in children and adolescents. Discussion Hospitals should ensure that adequate resources are available for individuals presenting with self-harm, especially in the case of overcrowded EDs, and protocols need to be designed for those presenting with self-harm due to intoxication. In line with national policy, protocols for patients presenting during out-of-hours should be designed that can incorporate services from allied health multidisciplinary teams, social work, addiction services and counselling organisations. Given the lower rates of self-harm during school holidays for children and adolescents, the school environment must be considered in the context of mental health and self-harm public health prevention interventions.

Purpose: The few studies that have explored self-harm presentation times at hospital emergency departments (EDs) – an important factor that can determine if a patient receives a mental health assessment – primarily focus on adult samples. This study examined the times of self-harm presentations to EDs, self-harm methods used, mental health assessments, and admission data across different age-groups. Methods: Using data from the National Self-Harm Registry Ireland over a 13-year timeframe (2007–2019), this study compared times, days, seasons, methods of self-harm, and admission data for children (8–12 years), adolescents (13–17 years), young adults (18–25 years) and adults (> 25 years). Results: The majority of the 152,474 self-harm presentations (78.6%) for all ages occurred out-of-hours (outside the standard working hours or in-hours times of 09:00–17:00, Monday-Friday). The four hours before midnight had the highest proportions of self-harm presentations for adolescents (27.9%) and adults (23.1%), whereas the four hours after midnight had the highest proportion of self-harm presentations for young adults (22.9%). The 16:00-midnight timeframe had highest proportion of self-harm presentations in children (52.3%). Higher proportions of patients received a mental health assessment in-hours compared to out-of-hours among young adults (78.2% vs. 73.3%) and adults (76.1% vs. 72.0%). Self-harm presentations were lowest during summer months in children and adolescents. Discussion: Hospitals should ensure that adequate resources are available for individuals presenting with self-harm, especially in the case of overcrowded EDs, and protocols need to be designed for those presenting with self-harm due to intoxication. In line with national policy, protocols for patients presenting during out-of-hours should be designed that can incorporate services from allied health multidisciplinary teams, social work, addiction services and counselling organisations. Given the lower rates of self-harm during school holidays for children and adolescents, the school environment must be considered in the context of mental health and self-harm public health prevention interventions. [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.

Combining data-sharing models and algorithm technologies has led to new data flow structures and usage patterns. In this context, the presentation time of shared low-sensitivity information across platforms has become a crucial factor that affects user perception and privacy-regulation behavior. However, previous studies have not conducted an in-depth exploration of this issue. Based on privacy process theory, this study discusses the impact and potential mechanism of the presentation time (immediate or delayed) of shared low-sensitivity information across platforms on privacy-regulation behavior. Through a pre-study and two online survey experimental studies, which included 379 participants in total, we verified that the immediate information presentation time has a significantly higher impact on online vigilance and privacy-regulation behavior than the delayed condition, βdirect = 0.5960, 95% CI 0.2402 to 0.9518; βindirect = 0.1765, 95% CI 0.0326 to 0.3397, and users' perceived control as the moderating role influences online vigilance and privacy-regulation behaviors (preventive or corrective), βpreventive = −0.0562, 95% CI −0.1435 to −0.0063; βcorrective = −0.0581, 95% CI −0.1402 to −0.0065. Based on these results, we suggest that the presentation time of using shared low-sensitivity information across platforms should be concerned by companies' recommendation algorithms to reduce users' negative perceptions and privacy behaviors and improve user experience. [ABSTRACT FROM AUTHOR]

Reacting to a moving object requires an ability to estimate when a moving object reaches its destination, also referred to as the time-to-contact (TTC) estimation. Although the TTC estimation of threatening visually moving objects is known to be underestimated, the effect of the affective content of auditory information on visual TTC estimation remains unclear. We manipulated the velocity and presentation time to investigate the TTC of a threat or non-threat target with the addition of auditory information. In the task, a visual or an audiovisual target moved from right to left and disappeared behind an occluder. Participants’ task was to estimate the TTC of the target, they needed to press a button when they thought that the target contacted a destination behind the occluder. Behaviorally, the additional auditory affective content facilitated TTC estimation; velocity was a more critical factor than presentation time in determining the audiovisual threat facilitation effect. Overall, the results indicate that exposure to auditory affective content can influence TTC estimation and that the effect of velocity on TTC estimation will provide more information than presentation time. [ABSTRACT FROM AUTHOR]

Abstract Background Neurotypical individuals categorize items even during ultra-rapid presentations (20 ms; see Thorpe et al. Nature 381: 520, 1996). In cognitively able autistic adults, these semantic categorization processes may be impaired and/or may require additional time, specifically for the categorization of atypical compared to typical items. Here, we investigated how typicality structures influence ultra-rapid categorization in cognitively able autistic and neurotypical male adults. Methods Images representing typical or atypical exemplars of two different categories (food/animals) were presented for 23.5 vs. 82.3 ms (short/long). We analyzed detection rates, reaction times, and the event-related potential components dN150, N1, P2, N2, and P3 for each group. Results Behavioral results suggest slower and less correct responses to atypical compared to typical images. This typicality effect was larger for the category with less distinct boundaries (food) and observed in both groups. However, electrophysiological data indicate a different time course of typicality effects, suggesting that neurotypical adults categorize atypical images based on simple features (P2), whereas cognitively able autistic adults categorize later, based on arbitrary features of atypical images (P3). Conclusions We found evidence that all three factors under investigation — category, typicality, and presentation time — modulated specific aspects of semantic categorization. Additionally, we observed a qualitatively different pattern in the autistic adults, which suggests that they relied on different cognitive processes to complete the task.

Background: The time at which a self-harm presentation occurs has been shown to be a significant factor as to whether a patient receives a psychiatric assessment or not, which may benefit the patient's future care. This scoping review sought to identify studies that report on the peak time of day for self-harm presentations to hospital Emergency Departments (EDs). This could help hospital managers to properly allocate the appropriate services for self-harm patients when they are needed the most. Methods: A scoping review of the literature from the year 2000 until 30th June 2021 was carried out using the PubMed, Web of Science, Embase and the Cochrane library databases. Results: There were 22 studies that were included for data extraction. The findings from 20 of these studies indicate that self-harm presentations tend to occur outside of working hours (09:00–17:00, Monday to Friday). The majority of studies found that the peak time for self-harm presentations was in the hours before and after midnight. Conclusions: While this scoping review identified a satisfactory number of studies for data extraction, examination of time of day of presentation was a secondary outcome across most studies. Given that the majority of studies focused on adult samples, further research is necessary to investigate peak times for other age cohorts. More research on this topic is also needed in low- and middle-income countries. Consideration should be given to ensure that the necessary resources to treat hospital presenting self-harm are allocated outside of typical working hours. [ABSTRACT FROM AUTHOR]

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]

Clinostats are instruments that continuously rotate biological specimens along an axis, thereby averaging their orientation relative to gravity over time. Our previous experiments indicated that low-speed clinorotation may itself trigger directional root tip curvature. In this project, we have investigated the root curvature response to low-speed clinorotation using Arabidopsis thaliana and Brachypodium distachyon seedlings as models. We show that low-speed clinorotation triggers root tip curvature in which direction is dictated by gravitropism during the first half-turn of clinorotation. We also show that the angle of root tip curvature is modulated by the speed of clinorotation. Arabidopsis mutations affecting gravity susception (pgm) or gravity signal transduction (arg1, toc132) are shown to affect the root tip curvature response to low-speed clinorotation. Furthermore, low-speed vertical clinorotation triggers relocalization of the PIN3 auxin efflux facilitator to the lateral membrane of Arabidopsis root cap statocytes, and creates a lateral gradient of auxin across the root tip. Together, these observations support a role for gravitropism in modulating root curvature responses to clinorotation. Interestingly, distinct Brachypodium distachyon accessions display different abilities to develop root tip curvature responses to low-speed vertical clinorotation, suggesting the possibility of using genome-wide association studies to further investigate this process. [ABSTRACT FROM AUTHOR]

Combining data-sharing models and algorithm technologies has led to new data flow structures and usage patterns. In this context, the presentation time of shared low-sensitivity information across platforms has become a crucial factor that affects user perception and privacy-regulation behavior. However, previous studies have not conducted an in-depth exploration of this issue. Based on privacy process theory, this study discusses the impact and potential mechanism of the presentation time (immediate or delayed) of shared low-sensitivity information across platforms on privacy-regulation behavior. Through a pre-study and two online survey experimental studies, which included 379 participants in total, we verified that the immediate information presentation time has a significantly higher impact on online vigilance and privacy-regulation behavior than the delayed condition, βdirect = 0.5960, 95% CI 0.2402 to 0.9518; βindirect = 0.1765, 95% CI 0.0326 to 0.3397, and users’ perceived control as the moderating role influences online vigilance and privacy-regulation behaviors (preventive or corrective), βpreventive = −0.0562, 95% CI −0.1435 to −0.0063; βcorrective = −0.0581, 95% CI −0.1402 to −0.0065. Based on these results, we suggest that the presentation time of using shared low-sensitivity information across platforms should be concerned by companies’ recommendation algorithms to reduce users’ negative perceptions and privacy behaviors and improve user experience.

Background: Neurotypical individuals categorize items even during ultra-rapid presentations (20 ms; see Thorpe et al. Nature 381: 520, 1996). In cognitively able autistic adults, these semantic categorization processes may be impaired and/or may require additional time, specifically for the categorization of atypical compared to typical items. Here, we investigated how typicality structures influence ultra-rapid categorization in cognitively able autistic and neurotypical male adults. Methods: Images representing typical or atypical exemplars of two different categories (food/animals) were presented for 23.5 vs. 82.3 ms (short/long). We analyzed detection rates, reaction times, and the event-related potential components dN150, N1, P2, N2, and P3 for each group. Results: Behavioral results suggest slower and less correct responses to atypical compared to typical images. This typicality effect was larger for the category with less distinct boundaries (food) and observed in both groups. However, electrophysiological data indicate a different time course of typicality effects, suggesting that neurotypical adults categorize atypical images based on simple features (P2), whereas cognitively able autistic adults categorize later, based on arbitrary features of atypical images (P3). Conclusions: We found evidence that all three factors under investigation — category, typicality, and presentation time — modulated specific aspects of semantic categorization. Additionally, we observed a qualitatively different pattern in the autistic adults, which suggests that they relied on different cognitive processes to complete the task. [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 Simultanagnosia is a rare neuropsychological symptom characterized by difficulty recognizing global structures while preserving perception of local detail. The condition is classified into ventral and dorsal types. Clinical presentation of ventral simultanagnosia includes a reduced ability to recognize multiple visual stimuli rapidly, that is, part-by-part recognition. Here, we report a case of ventral simultanagnosia with a unique presentation; when short-duration visual stimuli were presented, the patient could perform global recognition by improving his part-by-part approach. To investigate the relationship between local and global perception bias and the duration of the present stimulus, we conducted a visual perception test using hierarchically organized Navon figures. Methods/Results The patient was a 62-year-old right-handed man who suffered from cerebral infarction in the right occipitotemporal lobe. He had no language dysfunction but exhibited left unilateral neglect, prosopagnosia, and ventral-type simultanagnosia. We conducted a visual perception test using the Navon figures and control figures as a visual stimulus. We randomly presented the figures for intervals of 0.2 or 20 s and let the patient report all the letters (global and/or local element) that he recognized. Global elements of the Navon letter were recognized a rate of 0% and 78.3% at intervals of 20 and 0.2 s, respectively, indicating that shorter presentation made the part-by-part approach less likely to manifest. Conclusions We assumed that the simultanagnosia in this case was caused by failure to maintain the initially perceived global information for a long period of time during visual presentation, due to right occipitotemporal damage. [ABSTRACT FROM AUTHOR]

Visual object recognition seems to occur almost instantaneously. However, not only does it require hundreds of milliseconds of processing, but our eyes also typically fixate the object for hundreds of milliseconds. Consequently, information reaching our eyes at different moments is processed in the brain together. Moreover, information received at different moments during fixation is likely to be processed differently, notably because different features might be selectively attended at different moments. Here, we introduce a novel reverse correlation paradigm that allows us to uncover with millisecond precision the processing time course of specific information received on the retina at specific moments. Using faces as stimuli, we observed that processing at several electrodes and latencies was different depending on the moment at which information was received. Some of these variations were caused by a disruption occurring 160–200 ​ms after the face onset, suggesting a role of the N170 ERP component in gating information processing; others hinted at temporal compression and integration mechanisms. Importantly, the observed differences were not explained by simple adaptation or repetition priming, they were modulated by the task, and they were correlated with differences in behavior. These results suggest that top-down routines of information sampling are applied to the continuous visual input, even within a single eye fixation.

Although objects with curved contours are generally preferred over those with sharp-angled contours, the strength of this preference varies according to several factors. In the present study, non-Western Japanese observers viewed and rated their preferences (e.g., liking or attractiveness) for real and meaningless objects with curved or sharp-angled contours. We varied the presentation time (90 ms vs. until a response was received) and the response measure (like/dislike vs. 1–100 rating scale). When using like/dislike ratings, a preference for curved objects was found only when images of real objects were presented briefly (90 ms), whereas this effect was reversed (i.e., increased preference for sharp-angled contours) when using the 1 to 100 scale under the until-response condition. In addition, the curvature effect was not observed for real objects when the like/dislike rating and the until-response condition were employed or when the 1 to 100 scale and 90 ms presentation time were used. The curvature effect for meaningless objects remained unstable regardless of presentation time or response measure. Similar to the preference for real objects, a preference for sharp-angled objects was observed when preference was measured using a 1 to 100 rating scale. Taken together, the present findings indicate that the preferences for curved objects were situation-dependent in Japanese observers. [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]

Reacting to a moving object requires an ability to estimate when a moving object reaches its destination, also referred to as the time-to-contact (TTC) estimation. Although the TTC estimation of threatening visually moving objects is known to be underestimated, the effect of the affective content of auditory information on visual TTC estimation remains unclear. We manipulated the velocity and presentation time to investigate the TTC of a threat or non-threat target with the addition of auditory information. In the task, a visual or an audiovisual target moved from right to left and disappeared behind an occluder. Participants' task was to estimate the TTC of the target, they needed to press a button when they thought that the target contacted a destination behind the occluder. Behaviorally, the additional auditory affective content facilitated TTC estimation; velocity was a more critical factor than presentation time in determining the audiovisual threat facilitation effect. Overall, the results indicate that exposure to auditory affective content can influence TTC estimation and that the effect of velocity on TTC estimation will provide more information than presentation time., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Lu, Li, Yang, Wang and Zhang.)

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]

Basic-level categorization has long been thought to be the entry level for object representations. However, this view is now challenged. In particular, Macé et al. [M.J.-M. Macé et al. (2009) PLoS One, 4, e5927] showed that basic-level categorization (such as 'bird') requires a longer processing time than superordinate-level categorization (such as 'animal'). It has been argued that this result depends on the brief stimulus presentation times used in their study, which would degrade the visual information available. Here, we used a go/no-go paradigm to test whether the superordinate-level advantage could be observed with longer stimulus durations, and also investigated the impact of manipulating the target and distractor set heterogeneity. Our results clearly show that presentation time had no effect on categorization performance. Both target and distractor diversity influenced performance, but basic-level categories were never accessed faster or with higher accuracy than superordinate-level categories. These results argue in favor of coarse to fine visual processing to access perceptual representations. [ABSTRACT FROM AUTHOR]

Background: Stroke is the second leading cause of chronic disability and death in the world. Educating the public and physicians about stroke-related symptoms are critical success factors in early stroke treatment. Aim: This study was carried out in order to assess acute stroke management strategies in a teaching hospital. Patients and Methods: The study included all consecutive patients admitted to the general medical ward during the period of March to November 2008 who had a diagnosis of acute stroke. The total number was 217 patients, presumed to have stroke during their initial evaluation in the emergency room. However, ward evaluation confirmed only 193 patients to have a diagnosis of acute stroke (sudden onset of any neurological deficit). Brain imaging was performed in 167 out of the 193 patients. Results were obtained for 140 patients. Results: The age of those with clinical and radiological evidence of acute stroke (n=140) was 65±12 years. Sixty-five were females. The median time elapsed between the onset of symptoms and the arrival to the hospital was 12 hours (range: 1-336 h). Females presented earlier than males (19 hours versus 35 hours; p<0.05). Forty-eight patients (34%) presented within the first four hours and 71 (51%) arrived after eight hours, whilst 8 patients (6%) were not able to determine the time of onset of symptoms. The mean time for brain image from hospitalization was 3.5±2.3 days with no gender difference. Ischemic infarction was reported in 104/140 (74%) patients, intracerebral hemorrhage was reported in 16 (11%) patients and brain ischemia with hemorrhagic transformation was reported in 14 (10%). Normal brain images were found in 6 (5%) patients. 108 patients (78%) received in-hospital aspirin treatment with a mean time to start aspirin 1.2±1.4 days. The mean length of stay in hospital was 7.5±3.7 days. Ninety-nine (80%) of the patients were discharged on aspirin. The in-hospital outcome was assessed by the Rankin Disability Status scale as static course (in 107 patients; 85%), improvement of neurological function (in 10 patients; 8%), deterioration of neurological function (in 1 patient; 1%), or death (in 8 patients; 6%). Conclusion: Hospital arrival and performance of brain image were both delayed. Delayed arrival was attributed to lack of ambulance with direct transportation to the acute care hospital, waiting at the emergency department, and public's unawareness of stroke symptoms. The delay in performing brain image is the limited access to CT/MRI facility on site and out of hours. Public and professional education campaign coupled with an effective acute treatment strategies are urgently needed. [ABSTRACT FROM AUTHOR]

Neurologically normal individuals show an attentional bias toward the left side, which results from right hemisphere activation during visuospatial tasks. The strength of this bias is influenced by various factors, such as line length, vertical elevation and presentation time. What remains unknown is how participants gather information via saccadic eye movements during task performance and how this relates to their responses. Eye movements were recorded while participants performed the landmark task. Fixations and saccades were both analysed to gain a complete understanding of eye movement patterns. Fixations tended to focus on the centre of the line, with few left-right differences. Saccades were examined by creating histograms illustrating all x-coordinates which were examined over the course of each trial. Interestingly, mean eye position varied with participant response, with an overall tendency to look to the right of centre. Results are consistent with prior research, which has primarily looked at fixations and demonstrates the necessity of examining saccades as well as fixations in order to see how eye movement patterns relate to pseudoneglect. [ABSTRACT FROM AUTHOR]

Neurologically normal individuals show a bias toward the left side of space, referred to as pseudoneglect due to its similarity to clinical hemispatial neglect. The left bias appears to be stronger in the lower visual field during free-viewing, which could result from preferential dorsal stream processing. The current experiments used modified greyscales tasks, incorporating motion and isoluminant color, to explore whether targeting dorsal or ventral stream processing influenced the strength of the left bias. It was expected that the left bias would be stronger on the motion task than on a task incorporating isoluminant color. In Study 1, similar left biases were observed during prolonged viewing for luminance, motion and red, but not green color. The unexpected finding of a leftward bias for red under prolonged viewing was replicated in Study 2. A leftward bias for motion was also evident during 150 ms viewing in Study 2. In Study 3, the left bias was not apparent when using a blue/yellow condition, suggesting the left bias for red under prolonged viewing was likely unique to red. Furthermore, the leftward bias for red disappeared under brief viewing conditions. It is suggested that dorsal stream processing likely underlies visual field differences in pseudoneglect. (JINS, 2012, 18, 251–259) [ABSTRACT FROM PUBLISHER]

We investigated how visual information is best presented to maximize the number of remembered items in a fixed time unit. In a memory task for images depicting real-world objects, we varied the number of images shown simultaneously, the presentation time, and the interstimulus interval (ISI). The viewing phase was followed by a two-alternative forced choice recognition task. We converted the percentage of correct answers into a capacity estimate scaled to a fixed time unit of 1 s to allow for comparisons across conditions. Our results showed that (1) presenting one image very briefly was always more efficient than simultaneously showing multiple images for longer periods; (2) for single images, the maximum encoding rate was fairly constant over a wide range of conditions, at 1.4 objects per second; (3) when testing was done a week later, memory capacity was the same for all conditions, irrespective of the presentation time and ISI at the initial viewing; (4) highly similar distractors led to worse performance than random distractors; and (5) showing an image twice for 100 ms was associated with worse performance than showing the image once, but for 200 ms. [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]

The- memory of hyperactive and non-hyperactive children for 'attended' and 'unattended' picture cards was compared under two conditions, Under Self Imposed Presentation (SI) conditions children set their own limits on presentation time while under Externally Imposed Presentation (EI) conditions children were encouraged 10 spend 30 seconds attending to the cards. Hyperactive children selected shorter presentation limes that non-hyperactive children and recognized fewer 'attended' cards under SI conditions, while die two groups performed equally well under EI conditions, These findings suggest that a major determinant of memory deficits in hyperactivity is a self imposed limitation on presentation time rather than more specific cognitive process limitations. [ABSTRACT FROM AUTHOR]

The gravitropic curvature of seedlings of lentil (Lens culinaris L. cv. Verte du Puy) grown in microgravity and stimulated on the 1 g centrifuge for 5 to 60 min was followed by time lapse photography in near weightlessness in the frame of the IML 1 Mission of Spacelab. In microgravity, the root tip could overshoot the direction of the 1 g acceleration after bending, whereas roots stimulated on the ground did not reach the direction of the gravity vector. On earth, there is, therefore, a regulation (inhibition of root curvature), which is gravity dependent. In space, the initial rate of curvature as well as the amplitude of curvature varied as a function of the quantity of stimulation (Q, in gmin). For a given quantity of stimulation, the rate of curvature remained constant for 80 min. The bending has thus a certain inertia, which is linked to the mechanism of differential growth. The presentation time (Tp) of the lentil root was calculated by extrapolation to zero curvature of the regression line representing either the initial rate of curvature or the amplitude of curvature at 2 h after the end of the stimulation. Tp was estimated to 27 and 26 s, respectively. These results confirm the values of Tp obtained by clinostats, and they also lead to a reconsideration of the causes of the kinetics of root curvature. [ABSTRACT FROM AUTHOR]

Characteristics of the geotropic response of de-etiolated mung bean hypocotyls are presented. Geotropic sensitivity is not confined to the apical tissue but exists throughout the responding zone. The presentation time is estimated to lie between 0 and 30s for this tissue. Anatomical features of the presumed geoperceptive tissues are described. Rapid sedimentation and cyclosis of statolith amyloplasts in living tissue are reported, which are fast enough not to preclude the possibility of receptor sites at or near the lateral wall of statocytes. [ABSTRACT FROM AUTHOR]

Visual object recognition seems to occur almost instantaneously. However, not only does it require hundreds of milliseconds of processing, but our eyes also typically fixate the object for hundreds of milliseconds. Consequently, information reaching our eyes at different moments is processed in the brain together. Moreover, information received at different moments during fixation is likely to be processed differently, notably because different features might be selectively attended at different moments. Here, we introduce a novel reverse correlation paradigm that allows us to uncover with millisecond precision the processing time course of specific information received on the retina at specific moments. Using faces as stimuli, we observed that processing at several electrodes and latencies was different depending on the moment at which information was received. Some of these variations were caused by a disruption occurring 160–200 ​ms after the face onset, suggesting a role of the N170 ERP component in gating information processing; others hinted at temporal compression and integration mechanisms. Importantly, the observed differences were not explained by simple adaptation or repetition priming, they were modulated by the task, and they were correlated with differences in behavior. These results suggest that top-down routines of information sampling are applied to the continuous visual input, even within a single eye fixation. • Light reaching our eyes at different moments is processed in the brain simultaneously. • We introduce a method to uncover the processing specific to each of these moments. • Processing is different depending on when information is received on the retina. • These variations are multiple and occur within a single short fixation. • These variations are at least partly top-down in origin and translate to behavior. [ABSTRACT FROM AUTHOR]

Space experiments have offered a unique opportunity to analyse the mechanism of gravisensing in plant roots. It has been shown that the strict structural polarity of statocytes observed on the ground is perturbed in microgravity: the amyloplasts move towards the proximal half of the cell and, at least in some cases, the nucleus becomes located further away from the (proximal) plasma membrane. It has thus been demonstrated that the amyloplasts do not move freely in the cytoplasm. Experiments using cytochalasin B (or D) have indicated that these organelles are attached to the actin network, probably by motor proteins. These findings have led to a new hypothesis on gravisensing the basis of which is that the tension in the actin filaments resulting from interaction with the statoliths would be transmitted to stretch-activated ion channels located in the plasma membrane (Sievers et al., 1991, In: Lloyd (ed) The cytoskeletal basis of plant growth and form, Academic Press, London New York, pp 169–182. Recently, it has been shown that the sensitivity of roots grown under 1 g conditions in orbit is less than that of roots grown in microgravity or under simulated weightlessness on clinostats. Since the location of the amyloplasts in microgravity is different from that in 1 g, the greater sensitivity observed could be due to different tensions in the actin network. [ABSTRACT FROM AUTHOR]