Bibliographic record
Abstract
The purpose of this study was to examine the effects of tryptophan, the amino acid precursor to serotonin, on neuropsychological performance. A dietary method of tryptophan manipulation was employed to temporarily raise, lower, or maintain circulating levels of tryptophan within the body, allowing the resulting cognitive and affective sequelae to be measured. A total of 73 participants (50 females, 23 males) completed this mixed-design, double-blind study. Participants were quasi-randomly assigned to one of three tryptophan conditions (augmented, depleted or balanced) and were provided with breakfast, lunch and a snack. A comprehensive neuropsychological test battery was administered 1.5 hours after completion of lunch. Analyses were conducted on each gender separately. No significant results were found for females. For the males, however, significant between-group differences were found for the Rey-O delayed recall, with those in the Depletion group scoring significantly higher than those in the Balanced or Augmented conditions. Males in the Augmented condition also performed better than those in the Balanced or Depleted condition on the speed component of the Ruff 2 & 7 Selective Attention Test. With regards to affect, males in the Augmented group demonstrated a near-significant difference on the PANAS positive affect scale on the fourth PANAS administration compared to those in the Depleted group. These differences in positive affect levels seem to be primarily driven by the trend in excitement levels between males in the Augmented and Depleted conditions over time. Results of this study support the hypothesis that dietary manipulations aimed at altering tryptophan levels had an effect on some cognitive tests and positive affect, at least with regards to males.
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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 | 0.000 | 0.001 |
| 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 | 0.001 |
| 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".