Arthur Koestler, in �The Act of Creation� wrote of the intimate relationship between humour and creativity; of �aha� and �haha�.

This is borne out by experiment and also has a plausible explanation in terms of brain function.

In a paper* published in the Journal Of Cognitive Neuroscience, four researchers from the Department of Psychology and Cognitive Brain Mapping Group at Northwestern University demonstrate that:

• watching humour (a Robin Williams comedy) improves creative problem solving
• watching an anxiety-inducing movie (The Shining) reduces it
• activity in the brain�s Anterior Cingulate Cortex (ACC) increases when in a good mood

The ACC helps to regulate our attention and hence our focus on a problem.

* “A brain mechanism for facilitation of insight by positive affect�
by Karuna Subramaniam, John Kounios, Todd B. Parrish, and Mark Jung-Beeman
Journal Of Cognitive Neuroscience March 2009, Vol 21(3) pp.415-32)