1. Non-healthy individuals |
 • Previous medical history for any chronic condition in the last three months, active disease, or abnormal physical examination as verified by a qualified physician. |
2. Casual smoking |
 • >6 cigarettes per day. |
3. Frequent, heavy alcohol consumption |
 • >21 units/week. |
4. Frequent, heavy caffeine consumption |
 • >4 caffeinated drinks/day. |
5. Gender: female |
6. Age: < 18 and > 60 years old |
7. Shift workers |
8. Participation in an investigational drug trial within the past two months |
9. Intake of any medication (prescribed, over the counter or recreational) including topical steroids and inhalers, within 48Â hours of the study initiation |
 • Urine sampling for testing for drugs of abusea |
Stage 1 (pharmacological validation) only |
10. Needle phobia |
Stage 2 (neurobehavioural investigation) only |
11. Left-handed or ambidextrous |
 • Tested with the Edinburgh Handedness Inventory [13] |
12. Dyslexia |
13. Claustrophobia |
14. Contraindication to MRI scan |
15. Non English-language users |