Implicit and Explicit Emotional Responses to Light Induced Milk Oxidation and Breakfast Meals
Emotional responses, whether approach or withdrawal motivated, are fundamental factors in all food-related experiences. In this research project four experiments were completed with the goal of contributing to the growing body of research related to food and emotions. Implicit (unstated) measures of attention, emotional expression, and motivational behavior tendencies were assessed as additional supportive information for explicit (cognitive) measures of acceptability and emotional response to food and attributes of food with quality and safety concerns. Differences in explicit responses were evaluated using a 9-point hedonic scale, check-all-that-apply (CATA) emotion term questionnaire, and a six basic emotion intensity ratings scale. Implicit responses of emotion, attention and motivational behaviors were measured using automated facial expression analysis (AFEA), eye-tracking technology, electrocardiography (ECG) and electroencephalography (EEG). An initial study on light-induced milk oxidation flavor quality indicated reliable explicit measures of emotion and consumer acceptability, while AFEA showed a wide range of facial expression. In a following study, five different control breakfast meal videos were created; three were matched with a nearly identical video that contained one of three food concerns, food spoilage quality, hygiene quality and safety. Explicit measures provided solid support for the expected explicit response differences between food concerning and control breakfast meal types. Implicit measures of heart rate, facial motor expressions and frontal cortex asymmetries (brain activity) were only minimally informative across each measure or conclusive across meal types. The use of time series statistical analyses illustrated temporal changes in emotions when compared to a control condition, which was not evident using traditional analysis of variance approaches. A visual attention study investigated use of eye tracking as an indicator of the emotional responses elicited. Eye tracking technologies, as well as the other implicit measures (ECG, EEG, and AFEA), encountered similar limitations pertaining to participant variability due to personal preferences and characteristics, as well as a need for standard methodologies with food as stimuli and appropriate control conditions. With further research in this area of study, implicit measures of emotion, attention and motivational behaviors may provide additional valuable information to more traditional explicit affective methodologies for a greater understanding of the overall consumer food experience.