Reflecting a stimulus index in the data report

Question

I have some doubts regarding the 'Selected Index' property. If I’m not wrong, this variable gives you the number/order of the stimulus that you are presenting in the event (in my case I have several melodies included in a Direct Sound element). In which order does it give you that number? It follows the same order as the items are put in the list of the element? I’m asking that because I want to register in the Report the item that is being presented in each trial, to compare the item that they are listening/seeing and their answer (to know if the participants are doing the task well or not). Thanks a lot!

Answer 1

Hi Lucia,

There are several elements in EventIDE that can handle material (stimulus) lists: e.g. Renderer, Direct Sound, 3D Viewport, etc. All these element have the 'Selected Index’ property that matches the order of library items in the element’s material list. For example, Selected Index=1 for the first item, 2 to the second and so on. The order is fixed, but you can change it at design time in Material List Manager. Once the list is formed, you can copy-paste it to other elements of the same class, if needed.

If you want to keep a name of presented audio clip in the data report, I would suggest a more convenient way. If you add a proxy variable on the ‘Selected Item’ property of the Direct Sound element, it will return to you the name of the played wave clip, rather than a clip index. Thus, an audio clip can be selected by the index in code snippets, but you record its name in the data report.