Presentation

From ACLab Wiki

[edit] File Types Overview

Experiments in Presentation consist of different file types:

• Experiment files (*.exp) - controls hardware settings (e.g., port input, port output, audio and video controls, etc.) You can change experiment files using the Presentation GUI.

• Scenario files (*.sce) - text files written in SDL language. According to Presentation they specify stimuli and their associated properties, and sequences of stimuli and associated properties. If your experiment is very short and has a fixed order of stimuli, you can use only experiment and scenario files. You can change scenario files with any text editor or the editor in Presentation (somewhat awkward but has SDL keyword highlighting).

• Template files (*.tem) - template files supplement scenario files, and are designed to make writing a scenario easier. Like scenario files, template files are text files and are written in SDL. You can edit template files with any text editor or the editor in Presentation.

• PCL-files (*.pcl) - most interesting to actually make your experiment reasonably flexible. You can change PCL files with any text editor or the editor in Presentation (has PCL keyword highlighting).

• for more details visit the Presentation website

[edit] Example Experiment

The example experiment consists of three separate sections: Trial A, B, and C. Each trial is explained in a separate set of instructions. You don't have to keep these separate, it was an arbitrary choice. The instructions are short and have a fixed order, so they use experiment, scenario, and template files but no PCL. The three trials A, B, and C use all four file types.

Note: Trial B and Trial C depend on a text file produced when running Trial A, meaning you cannot run Trials B and C separately, unless you change their code.

Trial A: Judging words according to two different instructions. Conditions and words are presented in random order with the restriction that half of the words are presented in condition 1 and the other half in condition 2.

• Instructions A: [download]
• Trial A: [download]

Trial B: The same words are shown again plus new words and non-words. The task is identical for all trials (lexical decision task). Conditions are presented randomly.

• Instructions B: [download]
• Trial B: [download]

Trial C: Yes/No recognition consisting of old words and new distractors as well as non-words. Instruction is identical for all trials (old-new recognition, including "new" judgments for non-words). Conditions are presented randomly.

• Instructions C: [download]
• Trial C: [download]