Hello,
I am working with the Neuropixel data, and the “Functional Connectivity” experiment paradigm. In that, there is a block of 10 minutes, where the “natural_movie_shuffled” is presented. I was curious about
how the shuffled frames were obtained, and if the same shuffled frames were presented in all experiments, or different shuffles were obtained on each day?
Since there were 20 repeats, were all these 20 repeats the same “movie” or was each presentation different?
In trying to access the .nwb file (for example session -778240327), I see the “frame” entry inside “/intervals/natural_movie_one_shuffled_presentations” to simply increase from 0 to 900, which I assume is just the frame number for the presentation, and does not reflect frameIDs with respect to the original video. I want to access the information of what visual cue/frame was present at each time point.
I tried the idea from this link , but it did not work since, I assume that was for the calcium imaging experiments, where the shuffled movies were not presented.
Thanks in anticipation,
Chinmay
The shuffled movie was created once by randomly permuting the frames in “Natural Movie One.” So the movie is identical for each repeat, and for each session.
The original movie is not available through the AllenSDK, but I can send it to you if you’d like.
Hi Josh,
Thank you again for your prompt reply. Yes, please that would be great if you could send me that video/frame stack for the same. My email is chinmay.purandare@gmail.com .
Thanks again,
Chinmay
I also need to access the shuffled movie for my research. Could you please send me the shuffled movie or frame data corresponding to the original one? My email is joshuayanginf@gmail.com.
Thanks for lending a hand on this. I would like the movie frames for the shuffled presentation as well. You can email me at awilliams@flatironinstitute.org
Another detail about stimulus presentation I wanted to confirm was, were the movie stimuli presented in the center of the screen at native resolution (height: 304 pixels * width: 608 pixels), with gray screen fill around the edges?
A spherical warp was applied to all stimuli (including movies) so that they covered the whole screen, with no gray regions. Details of the warping procedure can be found in the “Stimulus monitor” section of this whitepaper.
Thank you very much, I have received the file. I noticed the spherical warp transformation described in the white paper. I understand that the stimulus generation process has two stages:
Generate stimuli using specific parameters;
Warp screen transformation before presentation.
I wonder if I need to scale the movie frame to achieve the effect of covering the full screen after warping when generating movie stimuli. Specifically, I use ImageStim in psychopy to present movie stimuli frame. Should I set the size parameter to (1920, 960), or keep its original resolution (608,304), or use other parameters to ensure that the stimulus position is consistent with the situation during the experiment?
Thank you for your very valuable reply. I am currently trying to reproduce the stimulus presentation process for data analysis rather than reproducing the experiment. The openscope_loop repository looks very valuable and I will study it carefully. According to my understanding, the spherical transformation is to maintain the invariance of the stimulus projected onto the retina. I try to directly generate the stimulus and use the mask obtained by the make_stimulus_template function to determine the ROI, interpreting this stimulus as a stimulus projected directly onto the retina for subsequent analysis.