Abstract: The purpose of this research was to understand the emotions emitted by college students in response to viewing online digital representations of evidenced-based visual display design principles. The study focused on identifying an approach to the design of visual displays that reflects human information processing design principles applicable to online instruction and that contributes to the enhancement of students\' emotional engagement with online instruction. The study focused on investigating technological approaches to measuring the indicators of each participant\'s responses in two different emotional dimensions: emotional arousal (high/low) as detected by the Q sensor, and emotional valence (positive/negative) as detected by the CERT. This study included a large amount of data: 12,896 electrodermal activities to generalize people\'s emotional arousal changes over 124 representations and 104 subjects. Also, 851,701 facial expressions were collected to generalize the effects of people\'s positive emotion valence. A two-way ANOVA found a difference of emotional arousal in simple-text representations. The highest emotional arousal was on good color images (M=0.827) and the lowest emotional arousal was on poor texture images (M=0.632.). A one-way analysis of variance found the highest mean score (M=0.743) was at the format of one paragraph with the 1.0 line spacing. The lowest mean score (M=0.505) was the format of 3 columns. On the other hand, the fixed-mixed regression model predicted the increment of emotional valence and showed that visual variables had significantly different effects of facial expressions. The good digital visual display representations in color increased 0.023 of joy facial expressions. The good digital visual display representations in shape increased 0.063 of joy facial expression. When the format of 3 columns was shown on the screen, the participant\'s joy raised 0.104. Compared to other three formats, this was the highest increment. The findings of this research lead us to believe that to enhance student\'s emotional engagement in online instruction, a clear need exists to design digital visual displays that emitted their positive emotions. These positive emotions, in turn, may improve their affective experiences. In the reflections of the findings, they offer the statements and applications of representations are offered for online instructional designers and developers.