OK, we have a lot to unpack here. 

First, this headline was inspired by an op-ed in the BBC News by University of Richmond neuroscientist Kelly Lambert.  Lambert trained rats to drive rat-sized electric cars using operant conditioning, i.e. by rewarding them with treats when they completed each step in a task.

Second, Lambert and her team noticed that the trained rats became excited when given a neutral signal that they would soon drive a car and get treats.  Based on additional experiments, Lambert's article says that the rats seem to be experiencing joy.  

Yeah, maybe.  But, her extrapolation from rats to human happiness is well-established: Anticipation increases the value of an experience.  An example is the enjoyment most people get the week before an exotic vacation: Imagining all the things one will experience on the trip builds up excitement for it.

The neurochemistry of this effect is also known.  The motivation to do something valuable is driven by the binding of the neurotransmitter dopamine to evolutionarily-old regions in the brainstem.  Besides being fun, going on vacation is a big pain.  Packing, getting in planes, trains, and automobiles, eating weird food at weird times and not sleeping when you want to.  Dopamine ramps up metabolic resources so we can overcome these inconveniences to reach the pleasure of having new experiences, in new places, with new people.  

The dopaminergic motivation system is part of the brain's social-emotional valuation circuit, which we named Immersion, that Immersion Neuroscience’s app SIX quantifies.  When an activity is sufficiently valuable, the first thing that happens is a spike in dopamine that causes people to be "all in" on starting and continuing an activity.  For experiences with emotional value, which are most experiences, dopamine then causes another neurochemical, oxytocin, to be released, completing the circuit and generating a feeling of joy.  

Anticipation of joyful experiences is the key reason that that the SIX app links to users' calendars to build a portfolio of happiness-producing activities unique to each individual.  The SIX app runs in the background while users go about their days, often unaware of key moments that are highly valued by their brains.  SIX shares these key moments with users every week and a trained AI assistant uses these data to make suggestions for choices users can make to be happier.  These suggestions build anticipation, increasing the overall value of the experience.

An example that I shared in my book Immersion: The Science of the Extraordinary and the Source of Happiness was taking the Immersion Neuroscience team to Disneyland.  Of course, we measured our Immersion the entire day and discovered that for nearly every attraction, queuing up was more valuable neurologically than the rides themselves.  That is anticipation.  That is dopamine.  

The dopamine motivation system is so ancient, plants synthesize it as well as nearly every animal, so that rats that anticipate and perhaps even enjoy driving rat-cars are little different from that trip you're thinking about taking in your people-car.  

Where humans and rats differ in extent, if not kind, is the effect of oxytocin.  While most rats species are social, humans are hypersocial.  For us, adding a social element to anticipated key moments substantially increases their Immersion.  This dopamine-oxytocin valuation system demands that human emotional fitness involves others.  We do not thrive unless we are strongly socially attached to family, friends and work colleagues. Love is the foundation for thriving.

The SIX app shows users what they value the most and which individuals add value to experiences.  It only took me and my team 25 years to figure all this out and to launch a company to bring it to you.  For free.  I am so grateful to all my collaborators and the investors in Immersion Neuroscience who believed that measuring and increasing happiness in the world was a good use of their time, energy, and money.  I think they were right.  If you think so, too, start using SIX today.