How to run the perceptual staircase experiment cerebDurJND (cerebellar battery 2022-23)
Special running circumstances
This experiment is part of the cerebellar battery run in 2022-2023. For controls, it is in the SECOND session. For patients, it is in the THIRD session.
In this battery, participants come in for multiple sessions and do multiple experiments in a row. As such, this is a bare bones document on how to run the experiment. Procedures for consent, hearing screening, awareness surveys, general equipment set up, and payment are not included in this document. See the documents below for how these procedures are implemented in this multi-study session:
- Protocol for cerebellar battery: controls
- For patients
This is a perceptual experiment, using prefabricated tokens.
- For people running this study at UW: the tokens are located on the server.
- For people running this study at UCSF: the tokens were shared via Google drive. They should be copied into the folder that is returned when you run
fullfile(get_exptLoadPath, 'cerebDurJND', 'stimuli')
"In this experiment, you will be listening to three words, which will differ mainly in the duration of the vowel. You will then press a button on the keyboard to indicate if the second word sounded more similar to the first sound or the third sound. If you are not sure, just make your best guess."
At this point you can answer any questions they might have (there are also task reminders in each trial).
"You will start first with a practice phase, where we can make sure that the volume is okay and to get you used to the task. In order to move onto the full task, you will need to get at least 5 of the 6 practice trials correct."
This experiment starts with a practice phase so that participants can get used to how the task is run. The practice phase uses stimuli with very large intervals, so participants should be able to hear the difference. During practice, the participant will get feedback on if their answers were right or not. They will automatically move onto the full phase of the experiment once they get at least 5/6 practice trials correct.
Note: this experiment assumes that 100 ms is larger than the biggest JND among cerebellar patients, based on data from a different study (for these particular stimuli, it is 100 ms vs. 200 ms, so it is a very large proportional difference). However, if you get a participant that cannot complete the practice because they cannot hear the differences, please contact Robin right away so additional stimuli can be made, and adjustments to the code installed. There will not be an infinite loop---if the participant fails practice more than 5 times, you will be able to manually override.
Once they have passed the practice, they will go automatically to the main phase of the experiment. They will complete either 100 trials or until they get to 30 reversals, whichever is first. This will last about 10 minutes.
After the participant leaves
- If running at UW: the data will be saved in
C:\Users\Public\Documents\experiments\cerebDurJND\acousticData\. Copy the participant's folder into:
- If NOT running at UW: the data will be saved into the folder generated by
get_acoustSavePath('cerebDurJND'). Copy the participant's folder into the path generated by
If Matlab crashes during the experiment
As of 9/23/2022 there is no restart script to start the experiment over in the middle of the experiment.