0274 NON-VISUAL EFFECT OF LIGHT ON COGNITIVE BRAIN FUNCTION: AGE AND IMPACT OF LENS YELLOWING
Bibliographic record
Abstract
Light, particularly blue light, increases alertness, performance and cognitive brain responses, but age-related decrease in the effects of light has been reported. The extent to which these age-related modifications are caused by changes at the level of the eye (because of senile miosis and lens yellowing) or the brain is unclear. We conducted a neuroimaging protocol including 14 younger (20-30y), 12 older (60-80y) and 12 matched older healthy individuals with intraocular lens replacement after cataract surgery (IOL subjects), i.e. they differed from the healthy older group only in terms lens light absorption. Subjects completed two functional magnetic resonance imaging (fMRI) acquisitions while performing a working memory 2-back task (2b) and a simple letter detection “0-back” task (0b), once under blue monochromatic light (B) (480nm, 3x1013ph/cm2/s) and once under orange monochromatic light (O) (620nm, 3x1013ph/cm2/s). Each fMRI session was conterbalned and also included blocks of n-back task in darkness, as well as blocks of light alone (B, O). First, all blue blocks were contrast against blocks completed in darkness [(2bB+0bB+B)-(2bD+0bD)]. Results revealed common group effects with greater brain activations in lateral geniculate nucleus, lingual, calcarine sulcus and median occipital gyrus under blue light exposure (P corrected < 0.05). As a second step, in order to estimate non-visual impact of light, we computed the effect of blue versus orange light on cognitive brain responses [(2bB-0bB)-(2bO-0bO)]. Results revealed a main effect of group (P corrected < 0.05) with group differences in various regions including the cingulate cortex, median prefrontal cortex and hippocampus. Young subjects showed greater brain sensitivity to light as compared to IOL and older individuals. No significant differences were found between IOL and older with their natural endogenous lens. Our results confirm that the aging brain is still sensitive to blue light. However, both older groups showed reduced non-visual effects of light on cognitive brain responses as compared to the young. These results suggest that cerebral modifications, not the lens, underlie age-related reduced non-visual impact of light on cognitive brain responses. CIHR.
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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 | 0.000 | 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".