Balloons, tails and bubbles: depicting speech and thought out of the brain and into the clinic.

Illustrations of the internal workings of the brain often depict arrows. In contrast, many illustrations which depict the link between certain brain functions and the outside world harness a graphic technique more usually associated with forms of popular culture such as comics. This technique comprises a balloon containing an image or message linked either by a tail emanating from the mouth when representing speech, or by a stream of bubbles emanating from the head when representing thought. Although a pictorial speech device first appeared over two millennia ago, balloons with their linkages now have various important practical clinical applications, notably in autism spectrum disorders, profound deafness in children without neurocognitive impairment, and sexual health education.