In the late 1980s Floyd injected gerbils with a free-radical-trapping compound called phenylbutyl nitrone just before inducing a stroke.

FORBES: Brain Repair

Among them: Pets.com (with its crooning sock puppet), Outpost.com (flying gerbils) and Furniture.com (a smug, talking cat named George).

FORBES: Spin Control

These were then delicately injected into the inner ears of 18 deaf gerbils.

BBC: Deaf gerbils 'hear again' after stem cell cure

Gerbils were used as they are able to hear a similar range of sounds to people, unlike mice which hear higher-pitched sounds.

BBC: Deaf gerbils 'hear again' after stem cell cure

About a third of the gerbils responded really well to treatment with some regaining up to 90% of their hearing, while just under a third barely responded at all.

BBC: Deaf gerbils 'hear again' after stem cell cure

The gerbils were also tested for only 10 weeks.

BBC: Deaf gerbils 'hear again' after stem cell cure

Over 10 weeks the gerbils' hearing improved.

BBC: Deaf gerbils 'hear again' after stem cell cure

In addition to Danger Mouse and Sparklehorse, other artists appearing on Dark Night of the Soul include The Flaming Lips, Gruff Rhys of Super Furry Animals, Jason Lytle of Grandaddy and Admiral Radley, Frank Black of Pixies, Nina Persson of The Cardigans, Suzanne Vega, Vic Chesnutt, David Lynch and Scott Spillane of Neutral Milk Hotel, and The Gerbils.

NPR: First Listen: Danger Mouse And Sparklehorse Team Up With David Lynch For 'Dark Night Of The Soul'