Spatiotemporal properties of apparent-motion perception in aging
Bibliographic record
Abstract
Recent studies have found age-related declines in motion perception from random dot kinematograms (e.g. Bennett et al., Vis. Res., 2007; Norman et al., Perception, 2003). However, some temporal integration abilities seem to remain intact (e.g. Andersen & Ni, Vis. Res., 2008). Here, we used random-dot two-frame apparent motion stimuli to investigate whether such age-related changes in motion direction discrimination can be attributed to a decline in the ability to integrate visual information across space and/or time. Previous work using such stimuli has shown that the perception of apparent motion is influenced separately by the duration of the inter stimulus interval (ISI) between the two frames and the magnitude of spatial displacement of the dots (e.g. Baker & Braddick, Perception, 1985). In the current experiment, older (mean age: 69 years) and younger (mean age: 24 years) subjects reported the direction of motion of two sequentially presented random-dot patterns in a two AFC task. The patterns were presented for 100 ms each and were separated by a blank ISI that varied between 10 to 240 ms. The second pattern was identical to the first pattern, but was shifted to the right or to the left by a displacement ranging from 1.9 to 76 arcmin. The effect of age on direction discrimination performance varied with the amount of displacement. At the shortest and longest displacements, older subjects performed significantly worse than young subjects across all ISIs. At medium displacements, both age groups performed near ceiling at short ISIs, but performance decreased with increasing ISIs. This decline was significantly greater, and began at a shorter ISI, in older subjects. These findings indicate that older subjects integrate information across a smaller range of inter-stimulus intervals and spatial displacements compared to younger subjects.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
How this classification was reachedexpand
Full frame distilled prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.
Codex and Gemma teacher scores by category
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.001 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.000 | 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 teacher head, 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".