How to run: cerebReachAdapt

How to run cerebReachAdapt, reaching experiment that is part of cerebellar battery (2022-23)

Special consideration

This experiment is part of the cerebellar battery run in 2022-2023. For controls and patients, it is in the FIRST 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: 

  1. Protocol for cerebellar battery: controls
  2. For patients

What's special about this experiment

This is a reaching experiment, with a separate interface computer. 

The lights should be OFF for this experiment so the participant can only see the cursor, not their actual hand. 

Prepping for participant

These should not have any occasion to change between studies, but it is good to check anyway. Note that you should run these checks on the REACHING computer which is on the cart (not Quiberon). 

Check sampling rate of tablet: 

  1. Click on Windows start button
  2. In the search at the bottom, type in Wacom tablet properties, and click on it when it appears
  3. Double click on the Intuos4 XL under "Device"
  4. Make sure it is in  to be in "Recognition Data" mode

Check refresh rate of monitor: 

  1. Click on the Windows Start button
  2. Type in settings, click when it appears
  3. Go to System > Display > Advanced Display Settings
  4. There should be two monitors in the dropdown to choose your display. Select Display 2: VG248
  5. The refresh rate is at the bottom. It should be 144.001 Hz 

Pre-experiment instructions

Start the experiment by typing in run_cerebReachAdapt_expt and hitting enter. Enter the required responses. Then place the pen on the tablet. 

Tell the participant: 

“The point of this experiment is to better understand how the brain controls reaching movements. We will be measuring how accurately you can reach to targets in different locations. Your data will be used as a normative baseline for future comparisons with neurological patients. So, please try your best to pay attention and follow all instructions.”

“In this experiment, you will be playing a game where you’ll be trying to make quick and accurate reaches to different target locations. For each trial, you will move the cursor to a home location in the center, which will be indicated with a circle. Then you'll make a quick reach to a target that appears somewhere on the screen. You should reach as quickly and accurately as you can, and slice through the targets rather than stopping at the target”

“Please take some time now to adjust the seat height and scoot in close to the work station. You will be making many reaches towards the edges of the tablet, and I want you to be able to do that without moving any parts of your body other than your arm. Keep the same posture throughout the experiment, and rest your other hand in your lap. Be sure to not swirl around in the chair.”

You will hold this pen at the red base with your dominant hand – maintain the same grip throughout the experiment.  (demonstrate)

There are no pre-planned breaks, but if you need to rest for a bit, just wait before moving the cursor to the center for the next trial.

“Do you have any questions?”

“I’ll give you a minute to get comfortable before turning out the lights.”

    After they are comfortable, turn off the lights, then press SPACE to start the experiment

    Baseline phase

    Tell the participant: “Move your hand to the start circle and wait for the target to appear. Your goal is to move your hand to the target. Reach through the target as accurately as possible in a quick straight line. Once you start moving, follow all the way through. If you hear a knocking sound, that means that you moved fast enough and far enough for a good trial.”

    Throughout the experiment, you should monitor how they are performing their reaches. You may have to issue corrections. Common issues:

    • When they get “Too Slow” message: “The too slow message means that you did not move fast enough for a valid trial. Remember to slice through the targets with your hand.” This is related to movement time, not reaction time 

    • If participant gets “slice through the target" message: “Remember to move accurately through the target in a quick, straight line.”

    • If they are picking up paddle: Please don’t pick up the paddle and just slide it along the table.

    Rotation phase

    Instructions will appear on the screen for the participant. In this phase, the cursor will move as they move their hand, but the direction that it moves will not correspond to where they are reaching. Their goal in this section is to move your hand directly to the target, ignoring the cursor. They should still reach as accurately as possible in a quick straight line and slice through the target. 

    If they have any questions, answer them. Press space when they are ready to begin. 


    There are two washout phases. Participants will see instructions on the screen before each phase. Answer any questions they may have. When they are ready to continue, press space. 

    Washout without feedback: In this block they will no longer see the cursor. They should continue to move their hand directly through the target.

    Washout with feedback: In this block they will see the cursor again. They should continue to move their hand directly for the target. 

    If Matlab crashes during the experiment

    There is no restart script. This is a relatively short experiment, and can be restarted if necessary. 

    Keywords:how to run, cerebellar, reaching, adaptation   Doc ID:121966
    Owner:Robin K.Group:Speech Motor Neuroscience Group
    Created:2022-10-19 12:43 CDTUpdated:2022-10-21 16:58 CDT
    Sites:Speech Motor Neuroscience Group
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