The Neural Basis for the Pleasure of Humor and Insight

http://geon.usc.edu/

Question

SfN, New Orleans, 2012

Ori Amir1, Irving Biederman1,2, Xiaokun Xu1 & Zhuangjun Wang2

1Department of Psychology, 2Neuroscience Program, University of Southern California

Where in the brain is the neural correlate of humor? Is it shared with the locus of activation when we appreciate the joy of insight of a creative solution?

A close up of a pig looking at book titles in a library.

(Hint: He has to rotate his head sideways to read the vertical titles) This is an example of an interpretation of a Droodle that is Humorous.

An open umbrella.

This is an example of a Droodle where the interpretation offers insight that is not humorous.

WHAT IS THIS? AND THIS?

Results B. Insightful vs. control

fMRI BOLD signal p<.05 averaged 5-16 seconds after the presentation of the text. A. Activation for humorous droodles with interpretive (funny) description minus activation for the same droodles with a mundane description. B. Activation for Insightful droodles (interpretive minus mundane). C. Areas that do not appear clearly on the surface maps above, but show significant activation for humor (top) and Insight (below).

2 types of droodles x 2 types of descriptions = 4 conditions Stimuli

Task: Rate the Funniness of the Droodle 1 - the description doesn’t make sense/you don’t understand the description 2 - you understood the description but you don’t find it funny (physical descriptions will often fall into this category) 3 - the droodle is A Little Funny 4 - the droodle is Funny

An fMRI Experiment Assessing the Neural Loci of the Pleasure of Humor and Insight

15 subjects viewed 200 droodles (100 humorous and 100 insightful. Half the droodles were followed by interpretive descriptions, the other half with physical descriptions. The order as well as the description type was balanced.

Left: The cortical ventral visual pathway. Density of black dots indicates the prevalence of opioid receptors which are greater in the later stages.

• The parahippocampal gyrus, LOC and striatum, that underwent markedly greater activation by humorous droodles (compared to control “mundane” descriptions) were largely the same areas activated by scenes and shapes that people prefer viewing. Insight droodles produced less activation in these areas.

• These later ventral pathway regions have higher densities of µ-opioid receptors then earlier visual areas (figure on right), and greater activation in these regions has previously been shown to correlate with perceptual pleasure.

• Both insightful and humorous droodles produced bilateral activation of the Striatum which may be related to the reward of experiencing humor or insight.

A. Humorous vs. control (Droodles are simple drawings that are otherwise uninterpretable without a verbal description.) In

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C. Additional Regions:

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Striatum

Striatum

Discussion & Conclusions

references: Biederman, I. & Vessel, E. A., 2006. Perceptual Pleasure and the Brain. American Scientist, 94, 249-255. Nishimoto, T., Ueda, T., Miyawaki, K., Une, Y., Takahashi, M. 2010. A normative set of 98 pairs of nonsensical pictures (droodles). Behavior Research Methods. 42(3): 685-691. Price, Roger. Droodles: The Classic Collection. Los Angeles: Tallfellow, 2000. Price, Roger. Oodles of Droodles. New York: H. Wolff Book. 1955. Price, Roger. Droodles #1. Los Angeles: Price/Stern/Sloan Publishers Inc. 1976. Supported by NSF BCS 04-20794, 05-31177, 06-17699 to I.B. We would like to thank JC Zhang for help with running fMRI subjects. “Geon-Brain” logo of the Image Understanding Lab (top right) is the work of Mark Lescroart.

Regions were activated by Humorous, but not Insightful, droodles: a) the left Amygdala, b) the right temporal pole, and c) the bilateral Orbitofrontal Cortex (OFC). These regions were also more activated for Humorous droodles that were rated as “Funny” compared to those rated as “A Little Funny.” (see figure on right). These areas may thus constitute the “funny bone of the brain.”

Humor, Insight and Perceptual pleasure

OFC

OFC

TP

TP TP

LOC LOC

TP TP

LOC LOC

OFC Abbreviations: OFC – Orbitofrontal Cortex LOC – Lateral Occipital Complex PHG – Parahippocampal Gyrus TP – Temporal Pole

Regions activated by Humorous droodles only Left: fMRI BOLD signal p<.005 averaged 5-16 seconds after the presentation of the text. Activation for humorous droodles with interpretive (funny) description that were rated by the subjects in the magnet as 4-Funny, minus activation for the humorous droodles that were rated by the same subjects as 3-A Little Funny.

Additional Droodles. Enjoy!

A ship arriving too late to save a drowning witch

An early bird catching a very strong worm

A highway for grasshoppers Germs avoiding a friend who caught antibiotics