Holding a response button down

[Jared G. Smith]

Hi

I am creating a line bisection task using a method of adjustment whereby 
participants are required to move (left or right) a vertical cursor 
superimposed on a horizontal line towards the perceived midpoint (the 
scripting for this resembles that of visual analogue scales).
Because in many trials the cursor begins placed some distance from the 
objective midpoint, rather than always having to press the response 
button to move the stimulus by one increment, I would like the user to 
be able to hold a keyboard button down in order to move the cursor in 
continuous increments (which would cease moving when the key was 
released) - rather like the effect of pressing a key down on a word 
processor. Does anyone know how such response movement could be achived?

Alternatively, does anyone have an example script for recording the 
duration of a button keyboard press response as I think I could use this 
duration to achieve continuous cursor movement in response to holding 
down a response button?

Would appreciate any help here. Thanks very much.

Best wishes

Jared G Smith

Research Fellow
School of Psychology and Clinical Language Sciences
University of Reading
Reading RG6 6AL
UK