Aging and the integration of orientation and position in shape perception
Bibliographic record
Abstract
The current experiments examined the effect of healthy aging on the integration of orientation and position information in shape perception. Following Day and Loffler (2009), conflicting contours were created by sampling the orientations of one shape (e.g., a rounded pentagon) with Gabors, and positioning them on the circumference of a different shape (e.g., a circle). In Experiment 1, subjects judged whether the conflicting contour looked more circular than a rounded pentagon of varying amplitude, which allowed us to estimate the perceived shape of the conflicting contour. The relative amount of position and orientation information was manipulated by varying the number of Gabors comprising the target contour. Orientation information dominated the percept for contours sampled with 15-40 elements, producing a strong shape illusion, but position information determined the shape with denser sampling. The magnitude of this orientation dominance effect was equal in younger and older subjects across all sampling levels. In Experiment 2, subjects discriminated five contours that differed in orientation and/or position information. Both groups showed poor discrimination between conflicting contours and their perceptually equivalent radial frequency patterns, confirming the main finding of Experiment 1. In addition, older subjects showed worse discrimination between two noncircular radial frequency patterns than younger subjects. In sum, integration of orientation and position information in shape perception is preserved with aging; however, older adults are less able to make fine shape discriminations between noncircular sampled contours.
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How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.001 | 0.002 |
| Meta-epidemiology (narrow) | 0.001 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.001 |
| Scholarly communication | 0.000 | 0.001 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.001 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".