Introminutes need to bring value. Focus on relaying that value so that in turn leaves an impression. That impression will turn into a thought later remembered and possibly relayed to another party. 

leaving the impression about the speaker will create a memory to serve later as they discuss their 7 minute topic and hopefully that 7 minute will show or prove what you relayed in your introminute abou the speaker. This allows the listeners to build confidence in the speaker and the knowledge they have in their area.