Recently our film club has been watching the comedies of Jacques Tati, to my mind one of the great comic artists of the last century, right up there with Chaplin and Keaton. Running all through his films is just that, people running. In a strange way, Tati seems to have understood something about our brains and happiness.
His characters are constantly in motion, going about in trucks, boats, cars, trains, buses, cement mixers--you name it. There is M. Hulot's absurd car in M. Hulot's Holiday. There are the big, garish American sedans in Mon Oncle. Endless scenes of traffic in Play Time. And his last feature film is, in fact, called Trafic. People moving about form one of his pervasive themes.
All these characters are looking for something. They are, in neuropsychologist Jaak Panksepp's term, SEEKING. Basically, this is a dopamine system that responds automatically and unconditionally to information from the body like "I'm thirsty" or "I'm hungry." And the system learns about things in the environment that predict satisfactions. You can think of this system as a foraging system, the thing that makes a rat sniff around looking for goodies. This dopamine system responds to stimuli that predict rewards, not to the rewards themselves. The system is active all the time during the day and during REM sleep. It generates search activities like foraging, investigating, sniffing, and, probably, dreaming. It is a system we share with all mammals, because we all have the same brain structure.
The core of this SEEKING system consists of pathways leading from nuclei in the substantia nigra and the closely related ventral tegmental area in the midbrain, at the top of the brain stem, the most ancient part of our brains. The two systems we want to pay attention to are the mesolimbic system and the mesocortical system. The "meso" in their names refers to the fact that they originate in the ancient midbrain (substantial nigra and ventral tegmental area). These nuclei generate dopamine and spritz it out widely into various systems in the higher parts of the brain. If you stimulate that pathway or, more techically, the lateral hypothalamic corridor, you get right away the most energized exploratory and search behaviors of which an animal is capable. From an evolutionary point of view, then, this system must be basic to our survival. And the mesolimbic and mesocortical systems are very basic indeed.
The mesolimbic system has to do with the feelings associated with this SEEKING behavior. The mesolimbic system originates in the midbrain--it's "meso"--and more specifically in the substantia nigra. And the "limbic" in its name refers to the limbic system, where emotions originate. The mesolimbic system extends on through the nucleus accumbens and up into the limbic system. It produces that good feeling, that invigorated feeling, that sense of anticipation, that we have when we actively seek thrills and other rewards. This mesolimbic system maintains a feeling that something exciting and interesting is going on. Think Freud's libido.
In short, in and of itself, using this system yields pleasure. We feel happy when we are SEEKING. And somehow Jacques Tati, bless his soul, knew this.
Psychological sources I've referred to:
Alcaro, Antonio, Robert Huber, and Jaak Panksepp. "Behavioral Functions of the Mesolimbic Dopaminergic System: An Affective Neuroethological Perspective." Brain Research Reviews 56.2 (Dec 2007): 283-321.
Holland, Norman N. "Literature and Happiness." PSYART: An Online Journal for the Psychological Study of the Arts. http://www.clas.ufl.edu/ipsa/journal/2007_holland01.shtml
Holland, Norman N. Literature and the Brain. Gainesville FL: PsyArt Foundation, 2009. Ch. 19. http://www.literatureandthebrain.com.