Keywords
Inhibitory Control
Cognition
How to Cite
Copyright © | All rights reserved.
The journal holds the exclusive copyright for the publication of this article under the terms of Brazilian law 9610/98.
Partial reproduction
The use of parts of the texts, figures and questionnaire of the article is free, being mandatory the citation of the authors and journal.
Total reproduction
It is expressly prohibited and must be authorized by the journal.
Abstract
Objective: To characterize the caffeine consumption profile of university students and investigate its association with inhibitory control performance. Methods: This quantitative, observational, analytical, cross-sectional study included 51 medical students. Expectations regarding the effects of caffeine were assessed using the Brief Caffeine Expectancy Questionnaire – Brazilian Version (B-CaffEQ-Br). Inhibitory control was measured using the Golden Interference Score of the Stroop Color and Word Test (SCWT). Correlation analyses and comparisons across expectancy tertiles were performed. Results: The mean B-CaffEQ-Br score was 77.8 ± 22.5 points. The mean Golden Interference Score was 10.7 ± 8.96. No statistically significant association was observed between caffeine-related expectancies and inhibitory control performance, according to both Pearson's correlation (r = −0.234; p = 0.099) and Spearman's correlation (ρ = −0.190; p = 0.182). Comparisons among expectancy tertiles also revealed no significant differences (Welch's ANOVA: F = 0.637; p = 0.535). Conclusion: An inverse trend was observed between expectations regarding the effects of caffeine and cognitive performance, although without statistical significance. Habitual caffeine consumption and individual tolerance were not assessed.
References
DELLELI S, et al. Distinguishing caffeine expectancy from pharmacological effects: a comparative review of experimental designs with future directions. Frontiers in Physiology, 2026; 17: 1865993.
DIAMOND A. Executive functions. Annual Review of Psychology, 2013; 64: 135-168.
FERRÉ S. Mechanisms of the psychostimulant effects of caffeine. Psychopharmacology, 2016; 233(10): 1963-1979.
FERREIRA LP, QUEIROZ RA. Consumo de cafeína e qualidade de vida entre universitários. Revista Brasileira de Promoção da Saúde, 2020; 33: 1-10.
FREDHOLM BB, et al. Actions of caffeine in the brain with special reference to factors that contribute to its widespread use. Pharmacological Reviews, 1999; 51(1): 83-133.
GALINDO MN, et al. The influence of placebo effect on craving and cognitive performance in alcohol, caffeine, or nicotine consumers: A systematic review. Frontiers in Psychiatry, 2020; 11: 849.
GARDINER C, et al. The effect of caffeine on subsequent sleep: A systematic review and meta-analysis. Sleep Medicine Reviews, 2023; 69: 101764.
GOLDEN CJ. Stroop Color and Word Test: A manual for clinical and experimental uses. Stoelting, Chicago; 1978.
HUNTLEY ED, JULIANO LM. Caffeine Expectancy Questionnaire (CaffEQ): construction, psychometric properties, and associations with caffeine use, caffeine dependence, and other related variables. Psychological assessment, 2012; 24(3): 592.
KAPELLOU A, et al. Genetics of caffeine and brain-related outcomes–a systematic review of observational studies and randomized trials. Nutrition reviews, 2023; 81(12): 1571-1598.
KLØVE K, PETERSEN A. A systematic review and meta-analysis of the acute effect of caffeine on attention. Psychopharmacology, 2025; 242(9): 1909-1930.
MCLELLAN TM, et al. A review of caffeine's effects on cognitive, physical and occupational performance. Neuroscience&Biobehavioral Reviews, 2016; 71: 294-312.
MENDES GF, et al. Brief Version of Caffeine Expectancy Questionnaire in Brazil. Frontiers in Nutrition, 2021; 8: 695385.
MILLER EK, COHEN JD. An integrative theory of prefrontal cortex function. Annual Review of Neuroscience, 2001; 24: 167-202.
NEHLIG, A. Is caffeine a cognitive enhancer? Journal of Alzheimer's Disease, 2010; 20: 85-94.
REYES CM, CORNELIS MC. Caffeine in the diet: country-level consumption and guidelines. Nutrients, 2018; 10(11): 1772.
SCARPINA F, TAGINI S. The Stroop Color and Word Test. Frontiers in Psychology, 2017; 8: 1-8.
SHOKR EA, et al. Caffeine expectancy, explicit and implicit memory performance among female nursing students: a placebo-controlled quasi-experimental study. BMC Nursing, 2026.
TEMPLE JL, et al. The safety of ingested caffeine: a comprehensive review. Frontiers in Psychiatry, 2017; 8: 80.
TRONCOSO-ESCUDERO P, et al. Caffeine and Cognitive Performance in Healthy Adults: Domain-Specific Effects and Dosing Considerations. Principles and Practice of Clinical Research, 2026; 11(4).
VAN PATTEN R, et al. The association between subjective and objective cognitive functioning from a transdiagnostic perspective: An umbrella review and meta-analysis. Clinical Psychology Review, 2025; 121: 102648.
WICHT CA, et al. Neural correlates of expectations-induced effects of caffeine intake on executive functions. Cortex, 2022; 150: 61-84.