Kant, Freud, Laughter and Brain Science

Many philosophers since Kant have tried to explain jokes, humor, and laughter, notably the French philosopher Henri Bergson and Sigmund Freud at the beginning of the twentieth century. Some of them saw in the joke and following laughter a mechanism of “bewilderment and illumination”. Freud wrote about that:

“The factor of ‘bewilderment and illumination’, too, leads us deep into the problem of the relation of the joke to the comic. Kant says of the comic in general that it has the remarkable characteristic of being able to deceive us only for a moment. Heymans (Zeitschr. f. Psychologie, XI, 1896) explains how the effect of a joke comes about through bewilderment being succeeded by illumination. He illustrates his meaning by a brilliant joke of Heine’s, who makes one of his characters, Hirsh-Hyacinth, the poor lottery-agent, boast that the great Baron Rothschild had treated him quite as his equal – quite ‘famillionairely’. Here the word that is the vehicle of the joke appears at first to be a wrongly constructed word, something unintelligible, incomprehensible, puzzling. It accordingly bewilders. The comic effect is produced by the solution of this bewilderment, by understanding the word. Lipps (Komik und Humor, 95) adds to this that this first stage of enlightenment – that the bewildering word means this or that – is followed by a second stage in which we realize that this meaningless word has bewildered us and has then shown us its true meaning. It is only this second illumination that produces the comic effect.” (Sigmund Freud, Jokes and their relation to the unconscious, 1905, pp. 27-28).

Now Daniel Elkan writes in NewScientist The comedy circuit: When your brain gets the joke (February 1, 2010):

“Take the following exchange from the classic British sitcom Only Fools and Horses, when an anxious "Del Boy" Trotter visits his doctor for a heart check-up. "Do you smoke, Mr Trotter?" asks the doctor. "Not right now, thank you doctor," he responds.

The joke's incongruity, of course, lies in the unlikely offer of a cigarette by a doctor to a patient concerned about his heart. It is only once we understand the mismatch that we get the joke. "Humour seems to be a product of humans' ability to make rapid, intuitive judgements" about a situation, followed by "slower, deliberative assessments" which resolve incongruities, says Karli Watson of Duke University in Durham, North Carolina.

But which parts of the brain carry out these processes? To find out, Joseph Moran, then at Dartmouth College in Hanover, New Hampshire, used functional MRI to scan the brains of volunteers while they watched popular TV sitcoms. The experiments revealed a distinct pattern of neural activity that occurs in response to a funny joke, with the left posterior temporal gyrus and left inferior frontal gyrus seeing the most activity. These regions are normally linked to language comprehension and the ability to adjust the focus of our attention, which would seem to correspond to the process of incongruity-resolution at the heart of a good joke (NeuroImage, vol 21, p 1055).

Further research, conducted by Dean Mobbs, then at Stanford University in California, uncovered a second spike of activity in the brain's limbic system - associated with dopamine release and reward processing - which may explain the pleasure felt once you "get" the joke (Neuron, vol 40, p 1041).

Examining one particular part of the limbic system - the ventral striatum - was especially revealing, as its level of activity corresponded with the perceived funniness of a joke. "It's the same region that is involved in many different types of reward, from drugs, to sex and our favourite music," says Mobbs, now at the MRC Cognition and Brain Sciences Unit in Cambridge, UK. "Humour thus taps into basic rewards systems that are important to our survival."

That reward explains the relaxation and laughter that we experience when we get to understand the incomprehensible or paradoxical elements in the joke: our brain is rewarded for having solved the puzzle because understanding a complex environment has survival value and should thus be rewarded.