Research on re-searching: interrupted foraging is not disrupted foraging.

In classic visual search, observers typically search for the presence of a target in a scene or display. In foraging tasks, there may be multiple targets in the same display (or "patch"). Observers typically search for and collect these target items in one patch until they decide to leave that patch and move to the next one. This is a highly rule-governed behavior. The current study investigated whether these rules are disrupted when the foraging is interrupted in various manners. In Experiment 1, the foraging was briefly interrupted and then resumed in the same patch. In Experiments 2 and 3, the foraging in each patch either ended voluntarily or compulsorily after a fixed amount of time. In these cases, foraging resumed in a patch only after all patches were visited. Overall, the rules of foraging remained largely intact, though Experiment 2 shows that foraging rules can be overridden by the demand characteristics of the task. The results show that participants tended to perform approximately consistently despite interruptions. The results suggest that foraging behavior in a relatively simple foraging environment is resilient and not easily disrupted by interruption.

Attenuation of spatial bias with target template variation.

This study investigated the impact of target template variation or consistency on attentional bias in location probability learning. Participants conducted a visual search task to find a heterogeneous shape among a homogeneous set of distractors. The target and distractor shapes were either fixed throughout the experiment (target-consistent group) or unpredictably varied on each trial (target-variant group). The target was often presented in one possible search region, unbeknownst to the participants. When the target template was consistent throughout the biased visual search, spatial attention was persistently biased toward the frequent target location. However, when the target template was inconsistent and varied during the biased search, the spatial bias was attenuated so that attention was less prioritized to a frequent target location. The results suggest that the alternative use of target templates may interfere with the emergence of a persistent spatial bias. The regularity-based spatial bias depends on the number of attentional shifts to the frequent target location, but also on search-relevant contexts.

No matter what you do, travel is travel in visual foraging.

In visual foraging, foragers collect multiple items from a series of visual displays (or "patches"). When the goal is to maximize the total or the rate of collection of target items, foragers must decide when to leave a depleted patch given that "traveling" from one patch to another incurs a temporal cost. In three experiments, we investigated whether the interposition of a secondary task during travel between patches in visual foraging altered patch-leaving behavior. Over the course of 10- or 30-minute experiments, participants foraged in simulated "berry patches" and traveled to the next patch at will. While they traveled, they either actively performed a secondary task or simply observed passing visual stimuli. Travel time was varied across conditions. The addition of a secondary task, regardless of its relevance to visual foraging, to traveling, or to both, did not impact patch-leaving times in the primary visual foraging task. In Experiment 1 and more weakly in Experiment 2, the patch-leaving decision was based on how long the travel took as predicted by the Marginal Value Theorem (MVT). In Experiment 3, however, patch-leaving did not depend on travel time. Participants 'overharvested' in a manner that suggests that they may have adopted rules different from those of MVT. Across all three experiments, patch-leaving did not depend on the nature of the travel.

Habit-like attentional bias is unlike goal-driven attentional bias against spatial updating.

Statistical knowledge of a target's location may benefit visual search, and rapidly understanding the changes in regularity would increase the adaptability in visual search situations where fast and accurate performance is required. The current study tested the sources of statistical knowledge-explicitly-given instruction or experience-driven learning-and whether they affect the speed and location spatial attention is guided. Participants performed a visual search task with a statistical regularity to bias one quadrant ("old-rich" condition) in the training phase, followed by another quadrant ("new-rich" condition) in the switching phase. The "instruction" group was explicitly instructed on the regularity, whereas the "no-instruction" group was not. It was expected that the instruction group would rely on goal-driven attention (using regularities with explicit top-down knowledge), and the no-instruction group would rely on habit-like attention (learning regularities through repetitive experiences) in visual search. Compared with the no-instruction group, the instruction group readjusted spatial attention following the regularity switch more rapidly. The instruction group showed greater attentional bias toward the new-rich quadrant than the old-rich quadrant; however, the no-instruction group showed a similar extent of attentional bias to two rich quadrants. The current study suggests that the source of statistical knowledge can affect attentional allocation. Moreover, habit-like attention, a different type of attentional source than goal-driven attention, is relatively implicit and inflexible.

Implicit learning of a response-contingent task.

In previous research, relative response speed was revealed to have been used as a predictive cue to guide attention to a target location, in a phenomenon known as "cueing by response." In this study, we explored whether responses can implicitly induce the use of cognitive control, especially in selecting and implementing task-sets. Participants were trained to perform tasks corresponding to different task cues during the training phase. Unbeknownst to participants, the response-contingent group's response to the previous trial determined task type in the subsequent trial, while that of the random group was randomly determined. When the task cue was removed in the testing phase, the percentage of correctly selected response-contingent tasks of the response-contingent group was at a greater level than the chance and the random group, implying that cueing by response can activate appropriate task-sets. The perceptual stimuli did not modulate the task cueing by response, and the response was directly associated with the task. Thus, the results show that top-down control can be carried out even without conscious awareness, using response as a novel type of cue.

Flexibility and stability of habit learning depend on temporal signal variation.

The visual system can learn statistical regularities and form search habits that guide attention to a region where a target frequently appears. Although regularities in the real world can change over time, little is known about how such changes affect habit learning. Using a location probability learning task, we demonstrated that a constant target location probability resulted in a long-term habit-like attentional bias to the target-frequent location. However, when the target probability changed over time in any pattern, the same amount of learning induced only a short-term bias and disrupted the formation of long-term search habits. Moreover, although temporal changes in regularity during initial learning interfered with the acquisition of a search habit, they did not modulate the already consolidated bias. These results suggest that the stability and flexibility of habitual attention learning depend on when and how the statistical regularities in the environment change. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Predictive factors of high comprehensive complication index in colorectal cancer patients using Enhanced Recovery After Surgery protocol: role as a safety net in early discharge.

PURPOSE: This study was performed to evaluate complications using comprehensive complication index (CCI) in colorectal cancer patients with implementation of the Enhanced Recovery After Surgery (ERAS) protocol, and to investigate the predictive factors associated with high morbidity rates. It can be used as a safety net in determining the timing of discharge. METHODS: A total of 335 consecutive patients who underwent elective colorectal cancer surgery between January 2017 and December 2017 at a single tertiary center were enrolled. Postoperative complications were defined as occurring within 30 days after surgery. The predictive factor analysis for the high CCI group was also performed. RESULTS: In total, 116 patients experienced postoperative complications. Wound-related complications and postoperative ileus were the most common. The mean CCI for overall colorectal cancer surgery was 9.1 ± 16.7. Patients featuring low CCI (<26.2) were 297 (88.7%) and high CCI were 38 (11.3%). In multivariable analysis, obstructive colorectal cancer (odds ratio, 3.278; 95% confidence interval, 1.217-8.829; P = 0.019) and CRP value on postoperative day (POD) 3-4 (odds ratio, 1.152; 95% confidence interval, 1.036-1.280; P < 0.010) were significant predictors for high CCI. CONCLUSION: The clinical usefulness of CCI in colorectal cancer patients with the ERAS protocol was verified, and it can be used for surgical quality control. More cautious care is needed and the timing of discharge should be carefully determined for patients with obstructive colorectal cancer or POD 3-4 CRP of ≥6.47 mg/dL.

Context affects implicit learning of spatial bias depending on task relevance.

Recent studies on the probability cueing effect have shown that a spatial bias emerges toward a location where a target frequently appears. In the present study, we explored whether such spatial bias can be flexibly shifted when the target-frequent location changes depending on the given context. In four consecutive experiments, participants performed a visual search task within two distinct contexts that predicted the visual quadrant that was more likely to contain a target. We found that spatial attention was equally biased toward two target-frequent quadrants, regardless of context (context-independent spatial bias), when the context information was not mandatory for accurate visual search. Conversely, when the context became critical for the visual search task, the spatial bias shifted significantly more to the target-frequent quadrant predicted by the given context (context-specific spatial bias). These results show that the task relevance of context determines whether probabilistic knowledge can be learned flexibly in a context-specific manner.

Successful Conservative Management of Hepatic Portal Venous Gas due to Anastomosis Leakage After a Sigmoidectomy.

In past decades, hepatic portal venous gas (HPVG) has rarely been reported, and the mortality rate has been very high. In most cases, surgical intervention was needed. Presently, abdominal computed tomography can be conveniently used to diagnose HPVG, which has various underlying causes and benign courses. We present the case of a patient with HPVG due to anastomosis leakage after a sigmoidectomy for diverticulitis; the patient was cured with conservative management.

Expression of the Cancer Stem Cell Markers CD44 and CD133 in Colorectal Cancer: An Immunohistochemical Staining Analysis.

PURPOSE: The aim of this study was to assess the expressions of CD44 and CD133 in colorectal cancer tissue by using immunohistochemical staining and to analyze the clinical significance of the expressions related to other clinicopathological data and survival results. METHODS: One hundred sixty-two patients with a biopsy-proven colorectal adenocarcinoma who were operated on between January 1998 and August 2004 were enrolled in this study. Immunohistochemical staining for CD44 and CD133 was performed on primary colorectal cancer tissue, metastatic lymph nodes, and synchronous and metachronous metastatic tumor tissues if available. RESULTS: CD44 expression was stronger in the primary tumor than in metastatic lymph nodes (P < 0.001), and CD133 expression tended to be stronger in primary tumor than in metastatic lymph nodes (P = 0.057). No significant correlation was found between the CD44 and the CD133 expressions. The cases with recurrence showed low expression of CD44 (P = 0.017). CD133 expression was lower in cases with elevated CA 19-9 serum levels (P = 0.028) and advanced T stage (P = 0.038). Multivariate analysis proved that low expression of CD44 was an independent prognosis factor for short disease-free survival (P = 0.028). CONCLUSION: Low CD44 expression was correlated with increased tumor recurrence and short disease-free survival, and low CD133 expression was associated with advanced tumor stage. We suggest that further studies be performed to evaluate whether the immunohistochemical method for determining the CD44 and the CD133 expressions is appropriate for exploring cancer stem-cell biology in patients with colorectal cancer.