Cita da Simone su 10 Aprile 2024, 9:12

Hi Robert, can you provide more details about your setup and experiment?

Cita da robert.lees su 12 Aprile 2024, 3:24

Hi Simone,

 

We are looking to compare motor unit recruitment between a Dynamic postural condition (Single Leg Squat) and static postural conditions (Seated Knee Extension tasks). We will use 4 grids across the Vastus Lateralis and 2 across the vastus medialis. We cannot measure torque (At least without influencing balance) during the single-leg squat, so we will try and use the EMG amplitude achieved in the single-leg squat task, and get the participant to match that amplitude during the static knee extension tasks. I am unsure whether this is the best method to do this open to any suggestions. I was just wondering how best to set this up and conduct it, any input is greatly appreciated.

Cita da Simone su 12 Aprile 2024, 9:34

Hi Robert,

Through OTBiolab+ you can run the trapezoidal feedback on a grouped track (grids) and the software will ask you to select two different electrodes. Then the trapezoidal will display the ARV of the differential of those two electrodes. There you can set the MVC and put the same value on both your tasks. If you are implementing your protocol in matlab/python maybe you can do that in a more complex way and look at more than one electrode at a time (calculate the mean for example)

I know from literature that if you calculate the cumulative spike train (sum of individual discharge rate or sum of spike train and then smooth the result) you'll get something similar to the force track (see attached image if curious). The problem is doing it during a task. You should calculate it later and repeat your task until your reach the desired value. I think it's unfeasible.

Another thing that I find problematic is that the blind source separation decomposition algorithm, as described in literature, is not reliable in dynamic condition.

 

Cita da astad su 21 Giugno 2024, 11:00

Hi all,

I am using the trapezoidal feedback in OTBiolab+ on the EMG signal (two channels from the grid, as Simone explained above). I wonder if there is a way to apply a low-pass or some other smoothing filter for this feedback? Otherwise it is quite jumpy and the subjects find it hard to follow.

Cita da Simone su 29 Giugno 2024, 2:25

Hi astad,

sorry for my late response, I was out of the office! Unfortunately there is no way to smooth it at the moment. The original idea was to use Trapezoidal feedback only with a FORCE channel, which is smooth. Then we implemented the possibility to use EMG channel.
The option to smooth the incoming data will be in implemented in the new software: OTBIOLAB24, you can download it for free from the software section. It has been officially released a couple of days ago. Still has something to fix and to implemented, of course, so if you have a chance to try the new trapezoidal and give your feedback it will be very useful for us to know your needs and what to modify/implement later.