Effects of tryptophan manipulation on neuropsychological performance

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