Presenting stimolous while a video is playing

[CarF]

Hi everyone, 

I work as a research assistant in neurophysiology and currently I'm doing some researches on ERP. 

A couple of months ago I started studying and using E-Prime 3.0 to set up some protocols and experiments and first of all, I would like to thank this forum where I found many ideas, tips and help. 

I need your help with an experiment I would like to do. In practice, I should be able to play a video (reproduced, without interructions, for the entire duration of the experiment) in the center of the screen, and at variable time intervals I should present a visual stimulus (a small image that stays on the screen for about 200ms) at the corners of the screen ( once top left, once bottom right, and so on), without overlapping the video. 

I tried to search here on the group but I could not find anything overlapping except a couple of old posts. Do you have any suggestions? 

Thanks in advance!

[David McFarlane]

Sorry it has taken me so long to get to this. A similar thread appears
at groups.google.com/g/e-prime/c/2M5D3z6JIg8, but in that case the added
content overlapped the video which makes things very difficult, and we
did not address the case when the added content does *not* overlap. So
let's address that now.

In short, you just have to make sure that the added content that you
want to show really does not overlap with the video. The Frame
properties (Size & Position) of your added content provide one way to do
that. You could also set the BackStyle of your added content to
"transparent", although the video will overwrite that anyway. I made a
little demo for myself using EP3 and verified that this will work
(should also work in EP2).

-- David McFarlane

[Magdi G.]

Hello everyone,

I am facing a similar problem. I want to show videos to participants, during which certain events will occur (e.g., presentation of white noise sounds, presentation of visual stimuli on top of the video). From previous threads, I understand that it is challenging to display something on top of a video. Instead, I could integrate these events into the video itself, which will then be shown to the participants.

Now, my question is: how can I send triggers to my physiological recording equipment to measure reactions to these events during the video presentation, and also ensure accurate timing? I want to measure GSR and pupil size.

Thanks!

Magdalena

[McFarlane, David]

Magdalena,

On the stimulus object that presents your movie, if you set Stop After to "No" then the movie will continue to play after the stimulus object itself exits. Then you may run other objects to provide the triggers at the appropriate times. For instance, you could set the Duration of the movie stimulus object to the latency before the first event, then add a simple Wait object with a Task Event to provide the trigger (please see other threads here for "gotchas" when using Task Events); and/or use Wait objects to provide triggers at other times during the movie playback.

Hope that helps,
-- David McFarlane

On 2024-06-05 Wed 2:23 PM, Magdi G. wrote:
> Hello everyone,
>
> I am facing a similar problem. I want to show videos to participants, during which certain events will occur (e.g., presentation of white noise sounds, presentation of visual stimuli on top of the video). From previous threads, I understand that it is challenging to display something on top of a video. Instead, I could integrate these events into the video itself, which will then be shown to the participants.
>
> Now, my question is: how can I send triggers to my physiological recording equipment to measure reactions to these events during the video presentation, and also ensure accurate timing? I want to measure GSR and pupil size.
>
>
> Thanks!
> Magdalena
>
> McFarlane, David schrieb am Montag, 1. August 2022 um 20:59:44 UTC+2:
>
> Sorry it has taken me so long to get to this. A similar thread appears

> at groups.google.com/g/e-prime/c/2M5D3z6JIg8 <https://urldefense.com/v3/__http://groups.google.com/g/e-prime/c/2M5D3z6JIg8__;!!HXCxUKc!wReoBugGk9_-J4RlFGRrCsyXKAkawt-PET_8BaRGmXQXcO9vrygniFGVeveNMlQgYBYK4meP_oS7t-TOqWyt9Q$>, but in that case the added