Inclusion Criteria:  45-75 years of age Free of cognitive impairment (Mini-Mental State Examination score of higher than 24) Absence of neurological disease Absence of gastrointestinal diseases Absence of prediabetes or diabetes No color blindness Have normal or corrected-to-normal vision No history of antibiotics or smoking over the past 3 months Agree to refrain from taking pre-or probiotic supplements during the study Agree to inform researchers of any changes in chronic medications during the study Body Mass Index (BMI) between 18.5 to 34.9 kg/m2 Habitual dietary fiber consumption of ≤12g/d (women) and ≤19 g/d (men) based on DHQ II Not consuming an extreme dietary pattern (e.g., vegan, keto, low FODMAP) No allergies to corn or maltodextrin, eggs, peanuts, tree nuts, wheat and soy Agree to maintain habitual dietary patterns throughout the study period Maintain their current level of physical activity Complete all necessary study questionnaires and to provide stool specimens as required.  Exclusion Criteria:  <45 or >75 years of age Presence of cognitive impairment (Mini-Mental State Examination score of lower than 24) Presence of neurological disease Presence of gastrointestinal diseases Presence of prediabetes or diabetes Color blindness Non normal or uncorrected vision History of antibiotics or smoking over the past 3 months Not agree to refrain from taking pre- or probiotic supplements during the study Not agree to communicate any changes in chronic medications during the study Body Mass Index (BMI) below 18.5 or greater than 34.9 kg/m2 Habitual dietary fiber consumption of >12g/d (women) and >19 g/d (men) based on DHQ II Consuming an extreme dietary pattern (e.g., vegan, keto, low FODMAP) Allergies to corn and/or maltodextrin Not agree to maintain habitual dietary patterns throughout the study period Not agree to maintain their current level of physical activity Not agree to complete all necessary study questionnaires and to provide stool specimens as required.