Feature-invariant processing of spatial segregation based on temporal asynchrony.

Temporal asynchrony is a cue for the perceptual segregation of spatial regions. Past research found attribute invariance of this phenomenon such that asynchrony induces perceptual segmentation regardless of the changing attribute type, and it does so even when asynchrony occurs between different attributes. To test the generality of this finding and obtain insights into the underlying computational mechanism, we compared the segmentation performance for changes in luminance, color, motion direction, and their combinations. Our task was to detect the target quadrant in which a periodic alternation in attribute was phase-delayed compared to the remaining quadrants. When stimulus elements made a square-wave attribute change, target detection was not clearly attribute invariant, being more difficult for motion direction change than for luminance or color changes and nearly impossible for the combination of motion direction and luminance or color. We suspect that waveform mismatch might cause anomalous behavior of motion direction since a square-wave change in motion direction is a triangular-wave change in the spatial phase (i.e., a second-order change in the direction of the spatial phase change). In agreement with this idea, we found that the segregation performance was strongly affected by the waveform type (square wave, triangular wave, or their combination), and when this factor was controlled, the performance was nearly, though not perfectly, invariant against attribute type. The results were discussed with a model in which different visual attributes share a common asynchrony-based segmentation mechanism.

Generalized Gaussian signal detection theory: A unified signal detection framework for confidence data analysis.

Human decision behavior entails a graded awareness of its certainty, known as a feeling of confidence. Until now, considerable interest has been paid to behavioral and computational dissociations of decision and confidence, which has raised an urgent need for measurement frameworks that can quantify the efficiency of confidence rating relative to decision accuracy (metacognitive efficiency). As a unique addition to such frameworks, we have developed a new signal detection theory paradigm utilizing the generalized Gaussian distribution (GGSDT). This framework evaluates the observer's metacognitive efficiency and internal standard deviation ratio through shape and scale parameters, respectively. The shape parameter quantifies the kurtosis of internal distributions and can practically be understood in reference to the proportion of the Gaussian ideal observer's confidence being disrupted with random guessing (metacognitive lapse rate). This interpretation holds largely irrespective of the contaminating effects of decision accuracy or operating characteristic asymmetry. Thus, the GGSDT enables hitherto unexplored research protocols (e.g., direct comparison of yes/no vs. forced-choice metacognitive efficiency), expected to find applications in various fields of behavioral science. This article provides a detailed walkthrough of the GGSDT analysis with an accompanying R package (ggsdt). (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Touch cannot attentionally select signals based on feature binding.

For human sensory processing, cluttered real-world environments where signals from multiple objects or events overlap are challenging. A cognitive function useful in such situations is an attentional selection of one signal from others based on the difference in bound feature. For instance, one can visually select a specific orientation if it is uniquely colored. However, here we show that unlike vision, touch is very poor at feature-based signal selection. We presented two-orthogonal line segments with different vibration textures to a fingertip. Though observers were markedly sensitive to each feature, they were generally unable to identify the orientation bound with a specific texture when the segments were presented simultaneously or in rapid alternation. A similar failure was observed for a direction judgment task. These results demonstrate a general cognitive limitation of touch, highlighting its unique bias to integrate multiple signals into a global event rather than segment them into separate events.

Red Dichromatic Imaging Improves the Recognition of Bleeding Points During Endoscopic Submucosal Dissection.

BACKGROUND: Previous studies have indicated that red dichromatic imaging (RDI) improved the visibility of gastrointestinal bleeding. AIMS: To investigate the recognition of bleeding points during endoscopic submucosal dissection (ESD) under RDI compared with that under white light imaging (WLI). METHODS: Consecutive patients scheduled to undergo esophageal or gastric ESD at a single center were enrolled. Paired videos of active bleeding during ESD under WLI and RDI were created. Six endoscopists identified the virtual hemostasis point on still images after random video viewing. The distance between virtual hemostasis and actual bleeding points was scored in four levels (0-3 points), and the association with the color value was analyzed in both WLI and RDI. RESULTS: We evaluated 116 videos for 58 bleeding points. The median visibility score and recognition rate were significantly higher for RDI than for WLI (2.17 vs. 1.42, p < 0.001 and 62.1% vs 27.6%, p < 0.001). Additionally, the recognition rate of trainees in RDI was higher than that of experts in WLI (60.3% vs. 43.1%, p = 0.067). The median color difference of RDI was significantly higher than that of WLI (8.97 vs. 3.69, p < 0.001). Furthermore, the correlation coefficient between the visibility score and color difference was 0.712 (strong correlation). CONCLUSION: RDI can provide better recognition of bleeding points than WLI during ESD. Therefore, further studies are warranted to investigate whether RDI improves ESD outcomes.

Psychophysical measurement of perceived motion flow of naturalistic scenes.

The neural and computational mechanisms underlying visual motion perception have been extensively investigated over several decades, but little attempt has been made to measure and analyze, how human observers perceive the map of motion vectors, or optical flow, in complex naturalistic scenes. Here, we developed a psychophysical method to assess human-perceived motion flows using local vector matching and a flash probe. The estimated perceived flow for naturalistic movies agreed with the physically correct flow (ground truth) at many points, but also showed consistent deviations from the ground truth (flow illusions) at other points. Comparisons with the predictions of various computational models, including cutting-edge computer vision algorithms and coordinate transformation models, indicated that some flow illusions are attributable to lower-level factors such as spatiotemporal pooling and signal loss, while others reflect higher-level computations, including vector decomposition. Our study demonstrates a promising data-driven psychophysical paradigm for an advanced understanding of visual motion perception.

Coarse-to-fine interaction on perceived depth in compound grating.

To encode binocular disparity, the visual system uses a pair of left eye and right eye bandpass filters with either a position or a phase offset between them. Such pairs are considered to exit at multiple scales to encode a wide range of disparity. However, local disparity measurements by bandpass mechanisms can be ambiguous, particularly when the actual disparity is larger than a half-cycle of the preferred spatial frequency of the filter, which often occurs in fine scales. In this study, we investigated whether the visual system uses a coarse-to-fine interaction to resolve this ambiguity at finer scales for depth estimation from disparity. The stimuli were stereo grating patches composed of a target and comparison patterns. The target patterns contained spatial frequencies of 1 and 4 cycles per degree (cpd). The phase disparity of the low-frequency component was 0° (at the horopter), -90° (uncrossed), or 90° (crossed), and that of the high-frequency components was changed independent of the low-frequency disparity, in the range between -90° (uncrossed) and 90° (crossed). The observers' task was to indicate whether the target appeared closer to the comparison pattern, which always shared the disparity with the low-frequency component of the target. Regardless of whether the comparison pattern was a 1-cpd + 4-cpd compound or a 1-cpd simple grating, the perceived depth order of the target and the comparison varied in accordance with the phase disparity of the high-frequency component of the target. This effect occurred not only when the low-frequency component was at the horopter, but also when it contained a large disparity corresponding to one cycle of the high-frequency component (±90°). Our findings suggest a coarse-to-fine interaction in multiscale disparity processing, in which the depth interpretation of the high-frequency changes based on the disparity of the low-frequency component.

M-PAST score is better than MAST score for the diagnosis of active fibrotic nonalcoholic steatohepatitis.

BACKGROUND: Clinical trials enroll patients with active fibrotic nonalcoholic steatohepatitis (NASH) (nonalcoholic fatty liver disease [NAFLD] activity score ≥ 4) and significant fibrosis (F ≥ 2); however, screening failure rates are high following biopsy. We developed new scores to identify active fibrotic NASH using FibroScan and magnetic resonance imaging (MRI). METHODS: We undertook prospective primary (n = 176), retrospective validation (n = 169), and University of California San Diego (UCSD; n = 234) studies of liver biopsy-proven NAFLD. Liver stiffness measurement (LSM) using FibroScan or magnetic resonance elastography (MRE), controlled attenuation parameter (CAP), or proton density fat fraction (PDFF), and aspartate aminotransferase (AST) were combined to develop a two-step strategy-FibroScan-based LSM followed by CAP with AST (F-CAST) and MRE-based LSM followed by PDFF with AST (M-PAST)-and compared with FibroScan-AST (FAST) and MRI-AST (MAST) for diagnosing active fibrotic NASH. Each model was categorized using rule-in and rule-out criteria. RESULTS: Areas under receiver operating characteristic curves (AUROCs) of F-CAST (0.826) and M-PAST (0.832) were significantly higher than those of FAST (0.744, p = 0.004) and MAST (0.710, p < 0.001). Following the rule-in criteria, positive predictive values of F-CAST (81.8%) and M-PAST (81.8%) were higher than those of FAST (73.5%) and MAST (70.0%). Following the rule-out criteria, negative predictive values of F-CAST (90.5%) and M-PAST (90.9%) were higher than those of FAST (84.0%) and MAST (73.9%). In the validation and UCSD cohorts, AUROCs did not differ significantly between F-CAST and FAST, but M-PAST had a higher diagnostic performance than MAST. CONCLUSIONS: The two-step strategy, especially M-PAST, showed reliability of rule-in/-out for active fibrotic NASH, with better predictive performance compared with MAST. This study is registered with ClinicalTrials.gov (number, UMIN000012757).

Does training with blurred images bring convolutional neural networks closer to humans with respect to robust object recognition and internal representations?

It has been suggested that perceiving blurry images in addition to sharp images contributes to the development of robust human visual processing. To computationally investigate the effect of exposure to blurry images, we trained convolutional neural networks (CNNs) on ImageNet object recognition with a variety of combinations of sharp and blurred images. In agreement with recent reports, mixed training on blurred and sharp images (B+S training) brings CNNs closer to humans with respect to robust object recognition against a change in image blur. B+S training also slightly reduces the texture bias of CNNs in recognition of shape-texture cue conflict images, but the effect is not strong enough to achieve human-level shape bias. Other tests also suggest that B+S training cannot produce robust human-like object recognition based on global configuration features. Using representational similarity analysis and zero-shot transfer learning, we also show that B+S-Net does not facilitate blur-robust object recognition through separate specialized sub-networks, one network for sharp images and another for blurry images, but through a single network analyzing image features common across sharp and blurry images. However, blur training alone does not automatically create a mechanism like the human brain in which sub-band information is integrated into a common representation. Our analysis suggests that experience with blurred images may help the human brain recognize objects in blurred images, but that alone does not lead to robust, human-like object recognition.

Examination on Factors Affecting Symptom Change after Drug Withdrawal in Patients with Mild Erosive Gastroesophageal Reflux Disease Undergoing Symptom-Controlled Maintenance Therapy with Acid-Secretion Inhibition Drugs.

INTRODUCTION: In patients with gastroesophageal reflux disease (GERD) on maintenance therapy with acid-suppressive drugs, it is not clear what background factors allow patients to discontinue the drugs. The aims of this study were to examine the relationship of the changes in the frequency and severity of gastrointestinal symptoms after discontinuation of acid-secretion inhibitors for erosive GERD (eGERD) with possible patient background factors and to identify factors that influence these changes. METHODS: This is a multicenter, open-label, interventional, exploratory study. eGERD patients with mild mucosal injury whose symptoms were under control and who were on maintenance therapy with acid-suppressive drugs were withdrawn from the drug treatment for 4 weeks. We examined the relationship of patient backgrounds (sex, age, body mass index, alcohol consumption, smoking habits), esophageal hiatal hernia, Helicobacter pylori infection, pepsinogen I and II concentrations and I/II ratios, blood gastrin levels before and after drug discontinuation with total score change in Frequency Scale for the Symptoms of GERD (FSSG). RESULTS: Of the 92 patients whose symptoms could be assessed before and after drug withdrawal, 66 patients (71.7% of the total) had FSSG <8 and no symptom relapse after the withdrawal. Furthermore, patient background factors that may be related to symptom relapse/non-relapse were examined, but no related factors were detected. The maintenance medications before discontinuation in the above 92 patients were a proton pump inhibitor (PPI) and vonoprazan (VPZ, a potassium ion competitive acid blocker). Since PPI and VPZ were administered to about the same number of patients, though incidentally, we additionally examined the relationship between patient background factors and symptom relapse/non-relapse by treatment group. As a result, no relevant background factors were detected in both groups. Although there were no significant differences between the two groups, the severity and frequency of symptom recurrence in the VPZ group tended to be higher than in the PPI group. CONCLUSIONS: Consideration of background factors is unlikely to be required in the discontinuation of maintenance therapy for eGERD. There was no significant difference in the extent of disease or frequency of recurrence during the discontinuation period, regardless of whether the drug before discontinuation was a PPI or VPZ.

On the assumptions behind metacognitive measurements: Implications for theory and practice.

Theories of visual confidence have largely been grounded in the gaussian signal detection framework. This framework is so dominant that idiosyncratic consequences from this distributional assumption have remained unappreciated. This article reports systematic comparisons of the gaussian signal detection framework to its logistic counterpart in the measurement of metacognitive accuracy. Because of the difference in their distribution kurtosis, these frameworks are found to provide different perspectives regarding the efficiency of confidence rating relative to objective decision (the logistic model intrinsically gives greater meta-d'/d' ratio than the gaussian model). These frameworks can also provide opposing conclusions regarding the metacognitive inefficiency along the internal evidence continuum (whether meta-d' is larger or smaller for higher levels of confidence). Previous theories developed on these lines of analysis may need to be revisited as the gaussian and logistic metacognitive models received somewhat equivalent support in our quantitative model comparisons. Despite these discrepancies, however, we found that across-condition or across-participant comparisons of metacognitive measures are relatively robust against the distributional assumptions, which provides much assurance to conventional research practice. We hope this article promotes the awareness for the significance of hidden modeling assumptions, contributing to the cumulative development of the relevant field.

Endoscopic Detachable Snare Ligation Therapy for Colonic Diverticular Hemorrhage Improves Procedure Time Compared to Endoscopic Band Ligation.

BACKGROUND: The clipping method is widely used in endoscopic hemostasis for colonic diverticular hemorrhage. Recently, rebleeding was shown to be less common in ligation therapy than in clipping. Ligation methods include endoscopic band ligation (EBL) and endoscopic detachable snare ligation (EDSL). No studies have compared procedure times for EBL and EDSL. The present study aimed to compare EDSL and EBL in terms of procedure time. METHODS: In this single-center retrospective observational cohort study, we evaluated the data of 39 patients who underwent EBL or EDSL for colonic diverticular hemorrhage. The primary and secondary outcomes measured were the total procedure time and early rebleeding rate, respectively. RESULTS: Among the 39 patients included in the study, 18 underwent EBL, and 21 underwent EDSL for hemostasis. The median total pro- cedure times for the EBL and EDSL groups were 50 (range, 30-80) minutes and 35 (range, 18-55) minutes, respectively, demonstrating that the total colonoscopy time was significantly shorter in the EDSL group (P < .001). The early rebleeding rate was 11.1% (2/18) in the EBL group and 4.8% (1/21) in the EDSL group (P = .246). CONCLUSION: Important improvements in procedure time were achieved in the EDSL group. Based on our results, we believe that EDSL may reduce patient and endoscopist burden.

Visual discrimination of optical material properties: A large-scale study.

Complex visual processing involved in perceiving the object materials can be better elucidated by taking a variety of research approaches. Sharing stimulus and response data is an effective strategy to make the results of different studies directly comparable and can assist researchers with different backgrounds to jump into the field. Here, we constructed a database containing several sets of material images annotated with visual discrimination performance. We created the material images using physically based computer graphics techniques and conducted psychophysical experiments with them in both laboratory and crowdsourcing settings. The observer's task was to discriminate materials on one of six dimensions (gloss contrast, gloss distinctness of image, translucent vs. opaque, metal vs. plastic, metal vs. glass, and glossy vs. painted). The illumination consistency and object geometry were also varied. We used a nonverbal procedure (an oddity task) applicable for diverse use cases, such as cross-cultural, cross-species, clinical, or developmental studies. Results showed that the material discrimination depended on the illuminations and geometries and that the ability to discriminate the spatial consistency of specular highlights in glossiness perception showed larger individual differences than in other tasks. In addition, analysis of visual features showed that the parameters of higher order color texture statistics can partially, but not completely, explain task performance. The results obtained through crowdsourcing were highly correlated with those obtained in the laboratory, suggesting that our database can be used even when the experimental conditions are not strictly controlled in the laboratory. Several projects using our dataset are underway.

Tannin-phytobezoars with Gastric Outlet Obstruction Treated by Dissolution with Administration and Endoscopic Injection of Coca-Cola®, Endoscopic Crushing, and Removal (with Video).

A 77-year-old man complained of postmeal vomiting and sustained general fatigue. An abdominal computed tomography scan showed massive gastric expansion and fluid storage. Gastroscopy revealed four gastric bezoars that were considered to have caused pyloric ring obstruction. The patient was asked to drink 500 mL per day of Coca-Cola® for 4 days. On the fourth day, we performed endoscopic crushing and removal by injecting Coca-Cola®, cutting the softened bezoar with endoscopic snares, and collecting the pieces with endoscopic nets. We herein report (with a video presentation) a rare case of tannin-phytobezoars endoscopically removed with the administration and injection of Coca-Cola®.

Risk factors for postoperative bleeding and early death in percutaneous endoscopic gastrostomy: A multicenter retrospective study.

BACKGROUND AND AIM: Comprehensive reports on the risk factors for bleeding and early death after percutaneous endoscopic gastrostomy (PEG) are limited. In this multicenter study, we retrospectively investigated the risk factors for bleeding and early death after PEG. METHODS: Patients (n = 1234) who underwent PEG between 2015 and 2020 at Osaka Medical and Pharmaceutical University and its affiliated hospitals (11 institutions in total) were evaluated for postoperative bleeding and early death (within 60 days) after PEG according to patient characteristics, construction method, medical history, medications, preoperative hematological findings, and perioperative adverse events. Multivariate logistic regression was performed to identify independent predictors of bleeding and early death after PEG. RESULTS: The risk factors for bleeding after PEG were PEG tube insertion using the modified introducer method (odds ratio [OR], 4.37; P = 0.0003), low platelet count (OR, 0.99; P = 0.014), antiplatelet therapy (OR, 2.11; P = 0.036), and heparinization (OR, 4.50; P = 0.007). Risk factors for early death were low body mass index (BMI) (OR, 0.89; P = 0.015), low serum albumin levels (OR, 0.50; P = 0.035), and comorbidity of active cancer (OR, 4.03; P < 0.0001). There was no significant association between bleeding and early death after PEG. CONCLUSIONS: We identified several risk factors for bleeding and early death after PEG. Risk factors for bleeding were PEG tube insertion using the modified introducer method, low platelet count, antiplatelet therapy, and heparinization. Risk factors for early death were low BMI, low serum albumin levels, and comorbidity of active cancer.

Outcomes of endoscopic submucosal dissection for gastroesophageal reflux disease (ESD-G) for medication-refractory gastroesophageal reflux disease: 35 cases underwent ESD-G including 15 cases followed more than 5 years.

BACKGROUND: Although some kinds of endoluminal surgery for patients with proton pump inhibitor (PPI)-refractory gastroesophageal reflux disease (GERD) have been reported, there are few reports on their long-term outcomes. In 2014, we reported the effectiveness of endoscopic surgery for PPI-refractory GERD, which we invented and named endoscopic submucosal dissection for GERD (ESD-G) in 2008. Thereafter, we accumulated more cases and monitored the patients' condition postoperatively and describe the outcomes herein. PATIENTS AND METHODS: This single-center, single-arm trial was conducted at the Osaka Medical and Pharmaceutical University Hospital. We compared outcomes between before and 3-6 months after ESD-G. Additionally, we investigated the outcomes of patients 5 or more years after ESD-G. RESULTS: We performed 42 ESD-G procedures in 35 patients between 2008 and 2020. In seven patients, ESD-G was performed twice for various reasons. The frequency scale for the symptoms of GERD score was significantly improved 3-6 months after ESD-G (22 → 10, p < 0.0001); the Los Angeles classification for reflux esophagitis was clearly improved after ESD-G (p = 0.0423). The number of reflux episodes was not decreased by ESD-G. There was a significant difference in the potency unit of gastric acid secretion suppressants for controlling GERD-related symptoms between baseline and 3-6 months after ESD-G (p = 0.0009). In patients without a history of distal gastrectomy who underwent ESD-G, the potency unit of gastric acid secretion suppressants significantly decreased 5 or more years after ESD-G (p = 0.0121). CONCLUSION: ESD-G may be effective in patients with refractory GERD-related symptoms without a history of distal gastrectomy.

A Case Series of Radiation-induced Hemorrhagic Gastroduodenitis.

Objective We examined the clinical course and treatment method of a case series of radiation-induced hemorrhagic gastroduodenitis with clinical signs. Methods This was a single-center retrospective observational study. Patients We included seven patients with radiation-induced hemorrhagic gastroduodenitis treated at our hospital between April 2014 and May 2020. Results One male patient each had cancer of the head of the pancreas, bile duct cancer, hepatocellular carcinoma, and ureteral cancer, whereas two women had recurrent endometrial cancer and one woman had recurrent cervical cancer. The onset occurred 3-5 months after the end of radiation treatment. Endoscopic examinations showed a red edematous mucous membrane in a fragile condition stretching from the antrum of the stomach to the duodenum, with telangiectasia and ulcer. For endoscopic hemostasis, five patients underwent argon plasma coagulation (APC), which was successful in three patients. Two of these were being administered an antithrombotic at the time. One case resistant to conservative treatment required repeated transfusion for recurring hemorrhaging over a short period of time and therefore underwent surgical treatment. Thereafter, the postoperative course was favorable. Conclusions Actively attempting hemostasis through APC and surgery is effective for treating radiation-induced hemorrhagic gastroduodenitis. The use of an antithrombotic agent might lead to a risk of repeated hemorrhaging. Therefore, repeated hemostasis through APC is crucial.

Administration of a standard dose of vonoprazan fumarate delays gastric emptying in Japanese healthy adults: a prospective clinical trial.

BACKGROUND: There is no established view of how gastric acid suppression affects the time for gastric emptying. Vonoprazan fumarate shows potent and durable gastric acid inhibitory effects, but its effects on gastric emptying have not been studied widely. We investigated the effects of vonoprazan fumarate on gastric emptying and measured serum gastrin and plasma ghrelin levels in healthy adults. METHODS: Ten participants were administered 10 mg vonoprazan fumarate daily for 14 days, then 20 mg vonoprazan fumarate daily for 14 days. The gastric emptying breath test was performed and serum gastrin levels were measured at baseline and after each medication administration period. The protocol was then repeated, with the gastric emptying breath test and serum gastrin and plasma desacyl-ghrelin levels measured at baseline and the end of the medication trial. RESULTS: Mean serum gastrin levels increased in a dose-dependent manner [baseline: 104.7 ± 50.4, after 10 mg protocol: 328 ± 123.8, after 20 mg protocol: 555 ± 378.8 (pg/mL, mean ± standard deviation), p = 0.0008]. There was a significant difference between the gastric emptying breath test Tmax at baseline and just after the 20 mg protocol (baseline: 45.5 ± 15.3, after 20 mg protocol: 60.5 ± 19.6 min, p = 0.0418). Plasma desacyl-ghrelin levels increased significantly just after the 20 mg protocol compared to those at baseline [baseline: 222.3 ± 106.4, after 20 mg protocol: 366.2 ± 178.6 (fmol/mL), p = 0.0008]. CONCLUSIONS: In healthy adults, 14 days of vonoprazan fumarate administration at 20 mg/day delayed gastric emptying. TRIAL REGISTRATION: This clinical trial was registered in the University hospital Medical Information Network Clinical Trial Registry (Trial No. UMIN000039199 and UMIN000042969).

Motion Direction Discrimination with Tactile Random-Dot Kinematograms.

Motion detection is a fundamental sensory function for multiple modalities, including touch, but the mechanisms underlying tactile motion detection are not well understood. While previous findings supported the existence of high-level feature tracking, it remains unclear whether there also exist low-level motion sensing that directly detects a local spatio-temporal correlation in the skin-stimulation pattern. To elucidate this mechanism, we presented, on braille displays, tactile random-dot kinematograms, similar to those widely used in visual motion research, which enables us to independently manipulate feature trackability and various parameters of local motion. We found that a human observer is able to detect the direction of difficult-to-track tactile motions presented to the fingers and palms. In addition, the direction-discrimination performance was better when the stimuli were presented along the fingers than when presented across the fingers. These results indicate that low-level motion sensing, in addition to high-level tracking, contribute to tactile motion perception.

Describing the Sensation of the 'Velvet Hand Illusion' in Terms of Common Materials.

When sandwiching two moving parallel metallic wires between both hands, one often experiences an unexpected tactile sensation known as the "velvet hand illusion" (VHI). Researchers have revealed the optimal conditions for inducing VHI, while the subjective nature of VHI remains obscure. In this article, we conducted a psychophysical experiment to investigate the quality and magnitude of the illusory sensation felt during VHI. Participants were asked to evaluate the tactile sensation of moving wires by giving tactile adjective and intensity ratings of the illusory sensation. In the same experiment, for the sake of comparison, participants also rated the sensation for various common materials one may encounter in daily life. We found that, as the intensity of the illusory sensation increased, the tactile sensation became softer, wetter, warmer, and more favorable. We also found that, when a strong illusion was reported, the sensation was similar to those for leather and fabrics rather than metallic wire, which suggests that the illusion indeed changes the perceived material category. These findings provide a better characterization of VHI as well as a better understanding of tactile texture perception.

Massive Ascites Caused by Primary Diffuse Large B-cell Lymphoma of the Jejunum: A Case of a Rare Initial Symptom.

A 74-year-old man presented with abdominal swelling. Computed tomography revealed massive ascites and localized thickening of the small intestinal wall. Enteroscopy showed ulcerative lesions along the circumference of the jejunum. Histological examination showed dense proliferation of large lymphoid atypical cells, and immunohistochemistry showed CD20 and CD10 positivity, CD3 negativity, and Ki67 labeling index >80%. Cytology of the ascitic fluid revealed large lymphoid cells. These findings suggest that small intestine primary diffuse large B-cell lymphoma (DLBCL) caused the ascites. Massive ascites as an initial symptom of primary DLBCL of the jejunum is rare. Herein, we describe this unusual presentation.