The previous research by one of our members in the research team (H. Miller) suggests a possible influence of oral nutrients intake of certain fat or carbohydrates (glucose, fructose) on executive control. On the other hand, another previous study from our group (L. Van Oudenhove) suggests a subliminal influence of intragastric administration of fatty acids on subjective and neural responses to negative emotion induction. The purpose of this study therefore is to examine the effect of intragastric administration of certain fatty acids and carbohydrates on executive control in healthy volunteers.

Therefore one group of healthy volunteers are invited to the study. The participants will be randomly administered one of the three fatty acid emulsions or placebo via a nasogastric tube in each of the visits. After the exposure period, participants will use a computer to perform there different tasks to measure executive control. During each study visit, regular measurements of emotion, physical sensations, as well as blood glucose will be assessed. Furthermore, an electrocardiogram will be continuously recorded for the calculation of vagal function.

Inclusion Criteria:

• N = 26 These numbers are based on a power calculation for a repeated measures ANOVA with one within-subject factor using Gpower software version 3.1.7 (http://www.psycho.uni-duesseldorf.de/abteilungen/aap/gpower3), indicating that these sample sizes are needed to achieve 90% power to detect a medium-sized effect (f = 0.25).
• Men & women
• Age: >17 years
• 20 ≤ BMI ≤ 25
• Of good mental and physical health

Exclusion Criteria:

Participants with one or more of self-reported points below will be excluded:

1. History of, or current presence of:

   • Psychiatric disorders (e.g., anxiety disorders, somatization disorder, eating disorders, depression, substance-related disorders alcohol abuse or dependence etc.)
   • Abnormal eating behavior (including restraint and emotional eating)
   • Abdominal/thoracic surgery
   • Neurological, endocrine or digestive related disorders
   • Head trauma with loss of consciousness
   • Other serious medical conditions
   • Use of any drugs, including cannabis, during the past 6 months

2. Current presence of:

   • Pregnancy
   • Medication use that affects the function of the gastrointestinal tract and/or affects the nervous system, psychotropics or painkillers
   • A recent accident or surgery that has not fully recovered

3. Other

   • Smoking
   • Women not taking hormonal contraception