There is no difference between the duration of the E-Prime tasks and the 
duration of the BOLD time series from the scan. There is likely a 
misunderstanding of what the duration should be, but I can’t help without 
knowing specifically what doesn’t line up in your opinion.

There have been two things that have confused other users:
1) The “Run Duration” reported in HCP publications is the total duration 
reported by the scanner. But, that includes ~9.36s for scanner preparation and 
collection of the SBRef volume. That time period occurs before the BOLD time 
series and before the fMRI task begins, and should not be factored into task 
2) At the beginning of most tasks (all but LANGUAGE), there is an 8s 
“countdown” period before the first event in the task. Those 8s are included at 
the beginning of the BOLD time series image, and are included in the timing 
information in the EV files. So, if you haven’t included them in your 
estimation of the task timing, you might think that the task was too short or 
the scan too long.

Please review Barch et al. (2013) which includes more detailed description of 
the tasks, and that should help you understand the timing information that 
we’ve released in the EV directories in the packages.


Greg Burgess, Ph.D.
Staff Scientist, Human Connectome Project
Washington University School of Medicine
Department of Psychiatry
Phone: 314-362-7864

On Feb 23, 2018, at 4:56 AM, HMZ <<>> wrote:

Dear HCP experts,

This is Meizhen Han from Peking University.

Thanks for releasing the 7 fMRI tasks written in Eprime software used in Main 
HCP. I downloaded and run them on the Sinorad fMRI Stimili System in our lab. I 
find there is a slight difference between the actual time duration and the 
theoretical time duration calculated by task design. In addition, according to 
the related articles published by HCP groups, the scanning time for each task 
is a little longer (several seconds) than the theoretical time.

I’m wondering whether did you encounter this slight delay in your experiment 
and data analysis, and how did you deal with it.

Any relevant information would be very helpful. Thanks in advance!

Meizhen Han
PhD student
Center for MRI Research
Peking University


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