Using a similar design as Roberts & Montgomery (2015) https://pubmed.ncbi.nlm.nih.gov/25391436/ I am trying to use Homer3 to calculate the average OxyHb and DeOxyHb concentrations at each of my 16 source channels. This is not an event response paradigm, but one in which we are interested in overall average activation in regions of the PFC while completing a 2-3 min task. Then each channel will be compared across two groups (Cannabis users vs controls) to see if cannabis users differ from control when doing inhibitory control tasks with cannabis cues.

For each task, there is a baseline period followed by a single event stim that marks the beginning of the task block. The behavioural measures for each task (Go/No-Go, Emotive Stroop, Stop Signal) are related to reaction time. Therefore the task block length for each participant will vary.

I am able to run a processing stream for each participant (changing the time values for hmr_BlockAvg for each individual), though when it comes to exporting output, Homer3 seems to be geared towards HRF. However, my experiment is not concerned with event-related responses, as described above.

Is the information I need contained within the output? I'm finding the whole thing extemely confusing.

Any pointers would be much appreciated.

P.S. I intend to do my statistical analysis in SPSS or R, so all I am really after is an average for blood concentions for each participant at each channel.