Perceptual filling-in

Beck, Alan, 2000, 'Cognitive mapping and radio drama', Consciousness and the Arts and Literature, Volume 1 Number 2, July 2000
http://www.aber.ac.uk/tfts/journal/archive/cog.html

I recognise the radio equivalent of invariants - elements perceptually invariant even under transformation. These crucially affect radio drama's limited vocabulary in the non-verbal domains and they are the means for generating expectations and my filling-in of missing information. Of course, when used creatively, invariants (in the play excerpt, the STORM SOUNDS and TOM-TOMS) offer the radio director many opportunities. This is just one particular approach to the relatively limited stock of radio drama's FXs (sound effects). Filling-in is the compensation that the listener makes for what radio has filtered out in its representation of the extra-radio world.