Negative emotions in old adults

conduct my study on emotional reactions of young adults vs old adults when they watch negative videos. They videos will include (negative) publicly known events in history and unknown events. There will be two groups with three participants in each group. Group A consists of old adults, group B consists of young adults. Each group will watch the four videos. One video will be related to the Holocaust and another video about the 9/11 event (for example). The two other videos will be about other random/unknown events:  The 4 videos will have negative stimuli. My hypothesis states that people react stronger when they watch a video of a publicly known (negative) event rather than unknown event. If the event of the exposure is commonly known, the emotional reaction is greater. Therefore, participants in group A will have greater emotional reactions than the ones in group B because the older adults have a greater reserve of knowledge about the event. The negative stimuli is highly relevant to the older adults.