Does Caffeine Facilitate Human Reward Learning Behaviors?

NCT05325502 | Active Not Recruiting

• 1 other identifier: CChronobiology
• Study Type: interventional
• Target: 36
• Locations: 1 country
• Sites: 1

Brief Summary

"Learning from the rewards" is underlying the formulation of knowledge and habits in daily life. Caffeine is the most commonly used "psychoactive" substance that could change one's mind state by affecting the brain and nervous system. By such effects, caffeine enhances reward signals - dopamine - in human brains. In this research study, we will find out whether taking caffeine acutely or daily can enhance reward learning processes.

Conditions

Caffeine

Outcome Measures

Primary Outcomes (1)

• The accuracy (% of correct answers) in implicit learning through different probabilities of monetary reward feedback

  Through a probabilistic selection task, participant will go through a training phase to learn the rules which options may be more likely to return monetary feedback, and the knowledge learned will be tested in a second phase where the task difficulty is increased, and no feedback is provided. The overall accuracy in the testing phases will be examined, as well as the accuracies in choosing or avoiding the highest and lowest reward-probability stimuli.

  1-hour after the second intake on the 7th day

Secondary Outcomes (2)

• The errors in motor inhibition (rates of false alarm) in a motor inhibition task

  1.5-hour after the second intake on the 7th day

• Salience attribution behaviors

  1.5-hour after the second intake on the 7th day

Other Outcomes (4)

• Self-report anxiety levels

  1-hour after the second intake on the 7th day

• Subjective sleepiness and alertness

  1-hour after the second intake on the 7th day

• heart rate measurement

  1-hour after the second intake on the 7th day

Study Arms (3)

Placebo

PLACEBO COMPARATOR

7 days placebo intake.

Dietary Supplement: mannitol

Acute caffeine

ACTIVE COMPARATOR

6 days placebo followed by 1 day caffeine intake.

Dietary Supplement: caffeine; Dietary Supplement: mannitol

Daily caffeine

EXPERIMENTAL

7 days caffeine intake

Dietary Supplement: caffeine

Interventions

caffeine DIETARY_SUPPLEMENT

two doses per day: 200 mg caffeine in the morning; 100 mg caffeine in the afternoon

Acute caffeine; Daily caffeine

mannitol DIETARY_SUPPLEMENT

two doses per day: 200 mg in the morning \& 100 mg in the afternoon

Acute caffeine; Placebo

Eligibility Criteria

• Age: 18 Years - 40 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64)

You may qualify if:

• Age ≥ 18 and ≤ 40
• Clinically healthy
• Non-smokers

You may not qualify if:

• Habitual caffeine intake \< 100 mg or \> 450 mg
• Pregnant or lactating women
• Women using hormonal contraceptives
• BMI \< 18.5 or \> 29.9
• Sleep disturbance or extreme chronotypes
• Nicotine or recreational drug users
• Depression, anxiety, psychosis, or neurologic disorders
• Severe heart or cardiovascular diseases
• Diabetes or metabolic diseases
• Under chronic medications
• Incapable to operate the tasks or comprehend the study information in German or English
• Users of the Bopomo alphates utilized as stimuli in the reward learning tasks
• Current enrolment in other clinical trials

Sponsors & Collaborators

• Yu-Shiuan Lin: lead

Study Sites (1)

Centre for Chronobiology, University Psychiatric Clinics Basel

Basel, Canton of Basel-City, CH-4002, Switzerland

Location

MeSH Terms

Interventions

Caffeine; Mannitol

Intervention Hierarchy (Ancestors)

Xanthines; Alkaloids; Heterocyclic Compounds; Purinones; Purines; Heterocyclic Compounds, 2-Ring; Heterocyclic Compounds, Fused-Ring; Sugar Alcohols; Alcohols; Organic Chemicals; Carbohydrates

Study Officials

• Yu-Shiuan Lin, PhD

  Centre for Chronobiology, University Psychiatric Clinics Basel

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: TRIPLE
• Who Masked: PARTICIPANT, INVESTIGATOR, OUTCOMES ASSESSOR
• Purpose: BASIC SCIENCE
• Intervention Model: CROSSOVER
• Sponsor Type: OTHER
• Responsible Party: SPONSOR INVESTIGATOR
• PI Title: Postdoc researcher

Study Record Dates

• First Submitted: March 28, 2022
• First Posted: April 13, 2022
• Study Start: May 5, 2022
• Primary Completion: December 31, 2025
• Study Completion (Estimated): December 31, 2026
• Last Updated: March 17, 2026

Record last verified: 2026-03

Data Sharing

• IPD Sharing: Will share
• Shared Documents: STUDY PROTOCOL, CSR, ANALYTIC CODE
• Time Frame: Data will be made available after publishing (estimated to be July 2023).
• Access Criteria: Researchers who are interested in using IPD data from ADoRe can either contact the Sponsor-Investigator (ys.lin@unibas.ch, Yu-Shiuan Lin, PhD) or access from ADoRe project on OSF (https://osf.io/wzf2y/). Please note that the data folder of this project will be only accessible after publishing.

Locations

CH (1)