1. A computer-implemented method of digital image analysis, the method comprising: identifying a topic of a portion of a presentation being provided to a human subject; obtaining first digital video of the human subject that indicates facial expressions of the human subject while the portion of the presentation is provided to the human subject; performing micro-expression analysis on the human subject using the first digital video; comparing results of the performed micro-expression analysis with the identified topic, and determining a reaction type of the human subject based on the micro-expression analysis with respect to a context of the topic; and modifying a manner of performing interaction with the human subject or other human subjects based on the comparing of results.