Tilt aftereffect spreads across the visual field.

The tilt aftereffect (TAE) is observed when adaptation to a tilted contour alters the perceived tilt of a subsequently presented contour. Thus far, TAE has been treated as a local aftereffect observed only at the location of the adapter. Whether and how TAE spreads to other locations in the visual field has not been systematically studied. Here, we sought an answer to this question by measuring TAE magnitudes at locations including but not limited to the adapter location. The adapter was a tilted grating presented at the same peripheral location throughout an experimental session. In a single trial, participants indicated the perceived tilt of a test grating presented after the adapter at one of fifteen locations in the same visual hemifield as the adapter. We found non-zero TAE magnitudes in all locations tested, showing that the effect spreads across the tested visual hemifield. Next, to establish a link between neuronal activity and behavioral results and to predict the possible neuronal origins of the spread, we built a computational model based on known characteristics of the visual cortex. The simulation results showed that the model could successfully capture the pattern of the behavioral results. Furthermore, the pattern of the optimized receptive field sizes suggests that mid-level visual areas, such as V4, could be critically involved in TAE and its spread across the visual field.

The Role of White Blood Cell Count in Perianal Pathologies: A Retrospective Analysis of Hematologic Malignancies.

Background and Objective: Infections are the most common cause of anal and perianal pathologies in patients with hematological malignancies. Perianal infection diagnosis in this group of patients is difficult; thus, a careful anorectal examination is necessary with imaging modalities. In addition, the literature reveals a knowledge gap in the approach to anal pathologies in patients with neutropenia during diagnosis or chemotherapy. This study aimed to examine our institutional data on perianal complications and investigate the relationship between the white blood cell-neutrophil count, perianal lesion, and the type of treatment in patients with hematologic malignancies during the neutropenic period. Methods: Patients with a hematologic malignancy, hospitalized for cytotoxic chemotherapy, complicated by perianal pathology, documented by at least one imaging method, were included in the study. Results: A total of 42 patients were included in the study. Most of them had acute leukemia, 31 were affected by acute myeloid leukemia (AML), and 7 by Acute lymphoid leukemia (ALL). There was no statistically significant relationship between the anal abscess formation, the neutrophil count, and a previous perianal pathology. Anal abscess development was significantly more frequent in acute myeloid leukemia. An inverse relationship was found between the total white blood cell number at onset and having a surgical intervention for anal pathology.In conclusion, this article has shown that white blood cell count at the time of hospitalization can affect the surgical intervention in patients with hematological malignancy (in the majority with acute leukemia) affected by anal pathologies occurring in the neutropenic period.