Men drinking beer
Men drink beer at a restaurant in Hanoi July 20, 2009. Reuters/Kham

Science has proven that close companions are on a similar wavelength. The brainwaves of good friends are said to match when seeing video clips of various subjects, as shown in MRI scans.

There's a popular saying that goes, “Birds with the same feather flock together.” Scientists now have proof that friends are really on the same wavelength.

Researchers had put 42 students in an MRI machine. The subjects were required to watch a series of videos featuring a wide variety of subjects, which include documentaries, comedy and music. The study, recently published in the journal Nature Communications, states that these patterns could be used to predict which students were pals.

It started with an army of business school students from Dartmouth's Tuck. Up to 279 students were asked whether they were friends with each of the other students.

If two respondents said yes, they were then considered friends for the purpose of the study. The next part of the study has seen 42 of the students lying in a functional MRI scanner as they watched videos for more than 30 minutes.

Some of the video clips lasted for only 88 seconds, while others ran for more than 5 minutes. These were picked to evoke a range of emotions in the participants.

Researchers explained that some people might think that a music video for the song "All I Want" was “sweet,” while others would find it in a different way. Another video was a debate on whether college football must be banned. Another presented a discussion about a speech by former US President Barack Obama. Also included were a video from a gay wedding, a documentary featuring a baby sloth sanctuary, highlights from a soccer match and a presentation by an astronaut on the International Space Station.

The group from UCLA and Dartmouth College reports that neural similarity was linked with a dramatically increased likelihood of friendship. "Neural responses to dynamic, naturalistic stimuli, like videos, can give us a window into people's unconstrained, spontaneous thought processes as they unfold," lead author Carolyn Parkinson said.

"These results suggest that we are exceptionally similar to our friends in how we perceive and respond to the world around us," the team added. The result of the study offers proof that "people tend to be friends with individuals who see the world in a similar way.”