<P> The German literary scholar and media theorist Friedrich Kittler attaches great relevance to the song, referring to its lyrics as well as to its technological arrangement . For him, the three verses stage the (sound) technological evolution from mono to stereo, culminating in total, "maddening" surround sound . </P> <P> In a 2008 paper in Journal of the Association of American Medical Colleges Fusar - Poli and Madini suggest that the song includes avant - garde techniques and philosophical lyrics can be approached and analysed from a psychological perspective . The line "Got to keep the loonies on the path" references the attempt to maintain order and establish sanity . The detached description of a lobotomy is demonstrated in line "You raise the blade, you make the change . You re-arrange me' till I'm sane". The line "I'll see you on the dark side of the moon", which became a famous metaphor of human irrationality, expresses that madness that is always present but invisible, waiting to be exposed . In Sigmund Freud's terms it would be the unconscious . </P> <P> Some releases of Dark Side of the Moon, for example TC - SHVL. 804 (cassette, New Zealand release) and Q4SHVL 804 (quad LP, UK release) have a different mix of "Brain Damage". During the closing instrumental, beginning at about 3: 02, after the second chorus and leading into the final track, "Eclipse", only Peter Watts' "lunatic laughing" is heard, repeatedly, unlike other versions which have the speech sample "I can't think of anything to say", then Peter Watts' laugh and another sample "I think it's nice (ha ha ha)". </P> <Ul> <Li> Roger Waters--bass guitar, lead vocals, tape effects </Li> <Li> David Gilmour--electric guitars, harmony vocals </Li> <Li> Richard Wright--Hammond organ, VCS3 synthesizer </Li> <Li> Nick Mason--drums, tubular bells, tape effects </Li> </Ul>

Who laughs on dark side of the moon