http://www.slate.com/articles/technology/users/2015/09/love_and_connection_in_the_internet_age_we_ve_got_this.html

Recently a group of Indiana University undergrads volunteered as test subjects in a modern love experiment. Researchers placed electrodes on their faces and feet, asked them to name their current romantic companion or crush, then led them through a simulated exercise in which they told that special someone how they felt, both over email and in a voicemail message.