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At least 91 records · Page 5Linked to original sources
PubMed1992

Separation discrimination with embedded targets.

Previous research has shown that separation discrimination thresholds are independent of the internal spatial scale (local spatial frequency) of the targets whose separation is being judged. The experiments reported here tested the generality of this conclusion for separation discrimination of targets that were embedded in an array of identical objects, where crowding could enhance the importance of the scale at which the individual target locations are encoded. No effect of the local spatial scale of the targets was found under these conditions.

Contrast Sensitivity↗
PubMed1988

Large-scale relative localization across spatial frequency channels.

Large-scale relative localization accuracy is measured with objects that stimulate different ranges of spatial frequencies. The author has previously made measurements using objects that stimulate only high-spatial-frequency channels or only low-spatial-frequency channels and found no effect of spatial frequency. In the present study, relative localization accuracy, i.e. interval discrimination, is measured with an object pair consisting of a low-spatial-frequency object and a high-spatial-frequency object. Relative localization accuracy for this cross-channel stimulus is as high as for the same-channel stimuli used previously, showing that the relative localization mechanism operates effectively across spatial frequency channels.

Humans↗
PubMed1992

[Localization disorders in squint amblyopia: horizontal line bisection and relative vertical localization].

We used two different procedures for the evaluation of spatial localization errors in strabismic and anisometropic amblyopes, strabismic alternators and normal control subjects: partitioning of horizontal lines and vertical alignment. We found defective spatial localization in the amblyopic eyes of squinters with both procedures. However, in the horizontal partitioning experiment, the control subjects also showed asymmetries between the two hemifields. Thus, there is no good baseline under these conditions for the results of the amblyopic eyes of squinters. Our results show that vertical alignment is the more appropriate procedure to quantify defective spatial localization in strabismic amblyopes.

Discrimination Learning↗
PubMed1986

Spatial cue utilization in chronically malnourished rats: task-specific learning deficits.

Rats whose mothers were maintained on either a 25% casein diet or an 8% casein diet and who were provided the same diet after weaning were tested on delayed spatial alternation or on one of a series of spatial localization problems using the Morris maze (Morris, 1981). Malnourished rats demonstrated perseverative deficits in the form of strings of consecutive errors on the delayed spatial alternation. Performance in the Morris maze indicated spatial localization ability and spatial memory processes were not impaired by chronic malnutrition in rats. The data suggest that complex processing of spatial information that includes flexible use of place cues over short intervals is impaired by malnutrition, while spatial localization per se and spatial mapping are not affected.

Animals↗
PubMed2026

Beyond benchmarking: an expert-guided consensus approach to spatially aware clustering.

Spatial omics technologies have revolutionized the study of tissue architecture and cellular heterogeneity by integrating molecular profiles with spatial localization. In spatially resolved transcriptomics, delineating higher-order anatomical structures is critical for understanding how cellular organization affects function. However, the reliability of current benchmarks of spatially aware clustering (SAC) methods is undermined by their narrow focus on Visium and brain tissue datasets and the incorrect interpretation of manual annotation as ground truth. Here we present SACCELERATOR, a community-driven, extensible framework that standardizes data formatting, method integration and metric evaluation, enabling rapid inclusion of new methods and datasets. Our analysis revealed substantial limitations in the generalizability and reproducibility of SAC methods and shows that anatomical labels commonly used as ground truths are often biased, error prone and unsuitable for benchmarking. Rather than ranking methods, we propose a consensus-guided workflow where descriptive spatial metrics highlight high-entropy regions of method disagreement, enabling targeted feedback for tissue experts. Applied to brain and cancer datasets, this approach uncovered biologically meaningful patterns overlooked by individual SAC methods and manual annotations, highlighting the need for iterative, expert-in-the-loop evaluation.

Benchmarking↗
PubMed1991

[Discrimination difficulties--expression of disordered relative localization?].

Spatial uncertainty was examined according to a procedure suggested by Bedell and Flom (1981) ("triangle procedure") and additionally with a line-division test designed by Kundt. A horizontal line of a length of about 20 degrees and a shorter one of 4.3 degrees was divided into two equal parts. Strabismic amblyopes mark the middle of such a line with less precision and greater uncertainty than visually normal subjects do. Visual acuity was measured by single optotypes (Landolt rings), as well as by line optotypes with spaces of 2.6 min of arc between each other (C-test). Surprisingly, there was little correlation between visual acuity--even line acuity--and localization tasks.

Amblyopia↗
PubMedDate not supplied

Egocentric localization changes following unilateral strabismus surgery.

We measured spatial localization (using an open-loop pointing task) monocularly in each eye of eight patients undergoing unilateral strabismus surgery. Most of these patients had some degree of binocular vision. We found that, in most cases, changes in spatial localization produced by surgery on the operated eye paralleled those found in the other eye, both in magnitude and duration. Unilateral surgery can have central effects on egocentric localization.

Adolescent↗
PubMed2026

A study on the differences in recovery effects of different types of nutritional supplements on competitive performance of esports athletes under mental fatigue.

BACKGROUND: To compare the effects of different nutritional supplements on the recovery of core competitive performance abilities in esports athletes following mental fatigue and to observe changes in the autonomic nervous system during recovery after nutritional supplementation by monitoring heart rate variability (HRV). METHODS: A randomized crossover within-subject controlled experimental design was adopted, including nutritional supplement type (caffeine, nitrate, Ginkgo biloba extract, catechins, placebo)&#x2009;&#xd7;&#x2009;mental fatigue state (initial, fatigued, post-supplementation). Twenty high-level first-person shooter (FPS) esports athletes were recruited. Mental fatigue was induced using a Stroop task. After ingesting the different supplements and resting for 60&#x2009;minutes, the participants completed assessments of shooting accuracy, shooting stability, spatial localization, and multitasking ability using the KovaaK's simulation trainer. HRV indices were also recorded to evaluate changes in autonomic regulation. RESULTS: For shooting accuracy, compared with the placebo condition, all four supplements significantly improved shooting accuracy scores following mental fatigue (all p&#x2009;<&#x2009;0.05); however, no significant differences were observed among the effects of the different supplements. For shooting stability, caffeine, nitrate, and catechins produced significant recovery effects on shooting stability (all p&#x2009; <&#x2009;0.05); however, no significant differences were observed among the effects of these three supplements. For spatial localization and multitasking ability, the improvements in these two abilities in the post-supplementation state may have resulted from natural recovery, and none of the four nutritional supplements demonstrated a significant recovery effect. The HRV results showed that indices including RMSSD and SDNN changed under some supplement conditions. CONCLUSIONS: Mental fatigue significantly reduced the competitive performance of esports athletes. Four types of nutritional supplements all promoted the recovery of shooting accuracy, while caffeine, nitrate, and catechins promoted the recovery of shooting stability. However, no additional recovery advantages of the nutritional supplements over placebo were identified for spatial localization or multitasking ability. Changes in HRV may reflect changes in autonomic regulation during recovery, but further research is still warranted.

Humans↗
PubMed1990

Proton spectral editing in the inhomogeneous radiofrequency field of a surface coil using modified stimulated echoes.

It is shown that the modified stimulated echo sequence, [theta](+/- x +/- y)-t1-[theta](+ x)-t2/2-[2 theta](+ x)-t2/2- [theta](+ x)-t1-Acq(+/- x +/- y), denoted as MSTE[2 theta]x according to the exciter phase of the 2 theta pulse, is able to perform proton spectral editing without difference spectra. On the other hand, this sequence appears to be suitable for spatial localization. Sensitivity and spatial selectivity of MSTE and conventional stimulated echo sequence (STE) are briefly compared. MSTE is applied to editing lactate in the rat brain using the locally restricted excitation of a surface coil.

Animals↗