Effect of Eggs and Egg Components on Cognitive Performance and Appetite in School-aged Children

One of five word lists composed of 15 words will be audio-visually presented to children. The majority of the words will be one syllable, and four words in each list will be two syllables long. The list will be presented at baseline and the children will be asked to recall as many words as possible at each time-point. The list will be presented for 2.5 minutes, and children will have 2 minutes for both immediate and delayed recall.

Assessed using a spatial pattern recognition test via the Membrain application. The test consists of a series of subtests where children will be presented a picture with patterns to study, and asked to identify a picture with the same pattern from a group of four images. This test will be at each time-point and takes approximately 1 minute to complete.

The continuous performance task (CPT) will be completed via the Membrain application. During the CPT task, children will be given a sequence of two letters to identify; for example respond to the detection of the letter "X" only when it is preceded by the letter "A". This task will be at each time-point and will take 3 minutes total to complete.

The Stroop task will be completed via the Membrain application. Children will be presented with a list of words presented in colors that match the word (congruent, the word 'red' presented in red) or colors that do not match the word (incongruent, the word 'red' presented in blue). Children will be asked to identify the color of the word, not the word itself. The task is scored for the number of correct and incorrect colors identified, as well as total time to completion. This test will be at each time-point and will take 1 minute to complete.

Measured using visual analogue scale (mm). Each VAS is a 100 mm line where they will place a pencil mark to describe their feelings.These emotions will be seperated into three categories including, subjective emotions (aggressive, angry, excited, disappointed, and frustrated), global vigour and affect (alert, sad, tense, effort, happy, weary, calm and sleepy), and wellness. These sub scales will be combined to compute an average total score for each category.

Measured using visual analogue scale (mm). Each VAS is a 100 mm line where they will place a pencil mark to describe their feelings. Average appetite will combine four questions (desire to eat, hunger, fullness, and prospective food consumption) to calculate the score.

Blood CCK (pmol/L). CCK concentration in serum will be determined in duplicate via enzymelinked immunosorbent assay kits (ELISA; Millipore, Billerica, Massachusetts).

Blood DPP4 (ng/mL). DPP4 concentration in serum will be determined in duplicate via enzymelinked immunosorbent assay kits (ELISA; Millipore, Billerica, Massachusetts).

Blood GLP1 (pmol/L). GLP1 concentration in serum will be determined in duplicate via enzymelinked immunosorbent assay kits (ELISA; Millipore, Billerica, Massachusetts).

Blood insulin (pmol/L). Insulin concentration in serum will be determined in duplicate via enzymelinked immunosorbent assay kits (ELISA; Millipore, Billerica, Massachusetts).

Blood glucose will be measured in whole blood using YSI 2300 STAT PLUS (YSI Incorporated, Yellow Springs, OH)

From plasma blood samples. Amino acids will be determined using the pre-column derivatization HPLC procedure. A plasma sample will be de-proteinizied with a 5-sulfosalicyclic acid solution, then centrifuged at 4°C and 18,400 G for 15 minutes. The amino acids will be derivatized from the sample with ortho-phthaldehyde reagent. The sample will then be analyzed using the Perkin Elmer Series HPLC System in the Ryerson University Analytical Centre.

From plasma blood samples. Fatty acids will be assessed via gas chromatography, an effective method to measure both the proportions and concentrations of fatty acids in plasma. A plasma sample will be prepared by trans-esterification of total lipid aliquots with a MeOH/HCl mixture and n-hexane. The sample will then be analyzed using the Perkin Elmer Auto-System in the Ryerson University Analytical Centre.

From plasma blood samples. Will be analyzed for choline using a fluorimetric assay; free choline will be oxidized by choline oxidase to betaine and H2O2 that reacts with a specific dye to form a pink colored product. The fluorescence intensity at 530/585 nm is directly proportional to the choline concentration in the sample.