A computer system for automatically constructing stimulus material

A FORTRAN system for constructing various kinds of stimulus materials is described. A user enters the basic components of an experiment (stimulus items, presentation parameters, trial identifiers, etc.) as files, and uses the system to combine the basic files, automatically constructing the desired stimuli. The system contains file-manipulation functions for combining files (including factorial combination), functions for separating out parts of a file, and functions for randomizing files. The user can use the standard FORTRAN function-embedding and function-definition features to easily specify elaborate operations on the basic files to construct complex stimulus files.