I am currently listening to the song "One LIttle Slip" by the Barenaked ladies, which many of you might remember from the movie Chicken LIttle

I am nostalgic when I listen to this song. The same way someone might become nostalgic when they smell a grandparent or relative's cooking. Most people think of nostalgia as remembering the good old days. Merriam Webster defines it as "the state of being homesick"; Oxford Dictionaries defines it as "A sentimental longing or wistful affection for a period in the past". However, the people who really study nostalgia have a slightly different perspective. Professor David Gerber of the University at Buffalo describes nostalgia as ambiguous and often a “flood of feeling[s] that diverts us temporarily from the present and immerses us in the past.” It is hard to describe nostalgia as an emotion because it is more of a state of mind or experience that is triggered by an outside force. The correct way to start this sentence should have been, "When I listen to this song I am flooded with nostalgic (overwhelming) memories."

A commonality between all definitions however is its positive connotation; it didn't always used to be that way. In the 17th century Swiss physician Johannes Hofer coined the term nostalgia as a mental illness for soldiers that longed to go home, and up until recent times everyone treated nostalgia as a weakness or disorder. Now many scientists are discovering all the benefits of nostalgia: such as increasing body temperatures and solving existential crises.

Tilburg University has found that listening to songs made people feel not only nostalgic but also warmer physically. In a follow up experiment Sun Yat-Sen University tracked students over the course of a month, and found that feelings of nostalgia were more common on cold days and people in a cool room (68 degrees Fahrenheit) were more likely to nostalgize than people in warmer rooms. It turns out humans have uniquely adapted/evolved to be able to enter a state of nostalgia and physical raise their body's temperatures (which I think is awesome).

Constantine Sedikides, from the University of Southampton's psychology department, believes “Nostalgia makes us a bit more human,” and considers the first great nostalgist to be Odysseus, who used memories of his family and home to get through hard times. North Dakota State University did a series experiments in which they induced nostalgia on on one group by playing and letting them read the lyrics to past hit songs. Afterward, they were more likely than the group that wasn't nostalgia induced to say that they felt “loved” and that “life is worth living.” They then did another experiment where they subjected some people to a bleak essay by an Oxford philosopher that stated life was pointless and everyone's contribution was "pathetic" or "pointless". Southhampton found that people were more likely to be nostalgic afterwards to fight off the angst of the essay, and that people who were nostalgic prior to the essay were less likely to agree with the depressing paper. Nostalgia gives people a sense of purpose, reminding people of what life can be.

However, there is a reason that nostalgia was considered a disease for centuries: fascination. Sometimes fascination with the past can inhibit progress for the future. Dr. Sedikides has found that when someone compares the past to the present and focuses on how much better the past is, then that is when it has negative effects. When someone thinks of the past to analyze a time in their life and what it meant, then nostalgia will have positive effects.

Now that you know what nostalgia is, how to use it, and what the benefits are, I will try to help use induce it. Technically smell is the strongest trigger due to its direct connection to the limbic system (first discovered by Sigmund Freud but that is another story), but other than going around smelling old people or childhood playgrounds, here is some help.

The IMdb page for the movie robots