Dear all,
I would like to know how much time does it take to set-up an experiment on an Active Two acquisition system.
The idea is the every user describe their acquisition system, setup method and time, so that good techniques can be shared with the other users.
Thanks a lot for your participation.
Julien Kronegg
Poll: how much time does it take for Active Two setup ?
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jkronegg
- Posts: 10
- Joined: Mon Jul 19, 2004 1:51 pm
- Location: University of Geneva/CVML, Geneva, Switzerland
- Contact:
Hi,
Ok, so I'm the first to answer.
Acquisition system:
We own a 64 electrodes ActiveTwo acquisition system (66 electrodes including CMS and DRL). The cap has 258 holders numbered A1 to H32, so that we can plug the electrodes virtually at any place. The electrodes are numbered using the standard geographical electrode names (eg. FT7, Iz).
We have a mapping table ElectrodeName->HolderName which is ordered in the A and B cable wire order, to minimize the time to find the electrodes. The person that plug the electrodes (supervisor) reads the mapping table to know where to plug the next electrode.
Setup time:
Using the configuration described, it takes 30 minutes to place the electrodes, including impedence verification (about 28 seconds for each electrode). The same setup time has been measured on 5 consecutive trials, so it doesn't seems that the setup time decrease with the supervisor experience.
Cleaning time:
That's not the first goal of this Poll, but I gave you the cleaning time. The scenario is the following: the supervisor unplug the electrodes, then the cap. The subject washs his head, while the supervisor cleans the electrodes (~40°C water to clean, soft towel to dry), the gel syringe and cap (~40°C water and a bit of mild soap to clean, soft towel to dry).
Unpluging the electrodes: 3 minutes (~2.8 seconds/electrode).
Subject head cleaning: less than 5 minutes.
Electrodes cleaning : 20 minutes (~19 seconds/electrode)
Cap cleaning: 35 minutes (~32 seconds/electrode)
Again, this timing is measured on several trials. Taking less time results in less well-cleaned material.
Julien Kronegg
Ok, so I'm the first to answer.
Acquisition system:
We own a 64 electrodes ActiveTwo acquisition system (66 electrodes including CMS and DRL). The cap has 258 holders numbered A1 to H32, so that we can plug the electrodes virtually at any place. The electrodes are numbered using the standard geographical electrode names (eg. FT7, Iz).
We have a mapping table ElectrodeName->HolderName which is ordered in the A and B cable wire order, to minimize the time to find the electrodes. The person that plug the electrodes (supervisor) reads the mapping table to know where to plug the next electrode.
Setup time:
Using the configuration described, it takes 30 minutes to place the electrodes, including impedence verification (about 28 seconds for each electrode). The same setup time has been measured on 5 consecutive trials, so it doesn't seems that the setup time decrease with the supervisor experience.
Cleaning time:
That's not the first goal of this Poll, but I gave you the cleaning time. The scenario is the following: the supervisor unplug the electrodes, then the cap. The subject washs his head, while the supervisor cleans the electrodes (~40°C water to clean, soft towel to dry), the gel syringe and cap (~40°C water and a bit of mild soap to clean, soft towel to dry).
Unpluging the electrodes: 3 minutes (~2.8 seconds/electrode).
Subject head cleaning: less than 5 minutes.
Electrodes cleaning : 20 minutes (~19 seconds/electrode)
Cap cleaning: 35 minutes (~32 seconds/electrode)
Again, this timing is measured on several trials. Taking less time results in less well-cleaned material.
Julien Kronegg
Impedence verification?
Hello
Setup time
About the topic of the pool, we have a 64 channels system with a 64 placeholder cap. This save us time, because we simply put the A1 electrode in the A1 placeholder, always the same. We also install 6 extra electrodes (4 EOG and 2 mastoid), who require to clean the skin. When we work in team of two, with at least one well-trained experimentor or technician, it's take less than 15 minutes.
However, we did not check the impedence (I was thinking that it was impossible to do with this system). We only look at electrodes with a lower sigal-to-noise ratio and at electrodes who clearly drift on the display. This checking could take between 1 minute (everything is ok) to a lot of time (according to the numbers of electrodes to fix).
Cleaning time
I think we take less time than you to clean the material. Only one person do the cleaning job. We leave the cap and the electrodes (separately) in water while the subjects clean his hair. We then clean the cap by inserting a pipe-cleaner in every hole, under the open water valve. We genly wash the tissue of the cap with water and soap, gently wring it with a soft towel and leave it dry. We then clean the electrodes with a wet tie towel. The cleaning process take about 20 minutes, one the subject finish with his hair.
Impedence ?
Can I ask you what you call impedence verification. Did you find a way to actually check the impedence?
Nicolas Robitaille
Setup time
About the topic of the pool, we have a 64 channels system with a 64 placeholder cap. This save us time, because we simply put the A1 electrode in the A1 placeholder, always the same. We also install 6 extra electrodes (4 EOG and 2 mastoid), who require to clean the skin. When we work in team of two, with at least one well-trained experimentor or technician, it's take less than 15 minutes.
However, we did not check the impedence (I was thinking that it was impossible to do with this system). We only look at electrodes with a lower sigal-to-noise ratio and at electrodes who clearly drift on the display. This checking could take between 1 minute (everything is ok) to a lot of time (according to the numbers of electrodes to fix).
Cleaning time
I think we take less time than you to clean the material. Only one person do the cleaning job. We leave the cap and the electrodes (separately) in water while the subjects clean his hair. We then clean the cap by inserting a pipe-cleaner in every hole, under the open water valve. We genly wash the tissue of the cap with water and soap, gently wring it with a soft towel and leave it dry. We then clean the electrodes with a wet tie towel. The cleaning process take about 20 minutes, one the subject finish with his hair.
Impedence ?
Can I ask you what you call impedence verification. Did you find a way to actually check the impedence?
Nicolas Robitaille
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jkronegg
- Posts: 10
- Joined: Mon Jul 19, 2004 1:51 pm
- Location: University of Geneva/CVML, Geneva, Switzerland
- Contact:
We also have cleaned the cap using a washing machine (low temperature, delicate tissues). The results are very good in term of cleaning and of cap resistance. This could be a good solution to use a washing machine from time to time...Cleaning time
We use the 3rd tab ("electrode offset") to ensure that all connected values are below 25.Can I ask you what you call impedence verification.
Julien