Multi Dose Effects of a Berry Extract Upon Mood, Attention and Memory in Healthy Young Adults.

The project will investigate the acute effects on human cognitive behaviour and mood of a single consumption of 3 fruit drinks versus a placebo. Drinks will be matched for volume, taste, appearance and sugars but will differ in the amount of total polyphenols. The 3 active treatment drinks contain a natural berry fruit grown in New Zealand by Plant and Food Research from commercial cultivars.

The study will follow a double-blind, counterbalanced, placebo controlled, repeated measures, crossover design with 36 healthy participants aged between 18 and 35 completing four study day sessions as well as one training/screening visit (five visits in total). On one occasion participants will receive a placebo, on another fruit drink 1, on another fruit drink 2 and on another fruit drink 3. Study days will be spaced one week apart to accommodate a wash out period. Fruit drinks will be made to include 500mg, 250mg or 125mg of polyphenols/60kg of body weight. Sucralose (artificial sweetener) will be added to make the drinks palatable. Participants will be screened for any intolerance or allergies to the drinks during the training/screening session . Trait anxiety will also be assessed during the screening visit using the State-Trait Anxiety inventory (STAI - Spielberger, 1966).

Psychometric tasks and mood scales will be delivered using the Computerised Mental Performance Assessment System (COMPASS), a purpose designed software application for the flexible delivery of randomly generated parallel versions of standard and novel cognitive assessment tasks that has previously been shown to be sensitive to nutritional interventions. .

Baseline cognitive testing will involve the dual task, Digit vigilance, Digit vigilance fast, Visual analogue scales, 3-back, corsi blocks, simple reaction time, telephone number task, word recognition, word recall, Bond-Lader mood scales and the state anxiety questionnaire (STAI).

Baseline On all 3 testing days participants will arrive at the lab in the morning (8:00 am), after an overnight fast, and firstly give a 10 mL venous blood sample taken by a trained phlebotomist. Participants will then complete one repetition of the COMPASS computerised cognitive assessment battery (baseline). Participants will then be orally supplemented with treatment in the form of a single serve juice drink (200ml per 60kg weight).