Hello All!
I'm interested in buying Alive however, i need to hear more about research purposes expiriences with Alive.
Is there any articles which were published and used alive as their mean to calculate skin conductance and heart rate?
Where can i get information regarding sampling rates and technical terms?
Research with Alive
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Ryan Deluz
- Posts: 232
- Joined: Fri Jun 19, 2009 7:46 am
Re: Research with Alive
Hi,
I'm not sure if anything is published yet, but there are a number of studies (those which I specifically know of are government funded) in progress using Alive, Dual Drive, and the Half Life 2 BioMod for Alive.
Alive is designed mainly for training of HRV and SCL. To analyze HRV and SCL using standard tools is possible, as all SCL and BVP (blood volume pulse, which determines heartrate) as well as heart rate measurements are stored in files external to Alive. I will assume you are using an IOM sensor, but the emWave sensor should be similar in most cases.
In your Documents/Alive Sessions/[user name] folder you will see the following files for each recorded session:
[session] kubios.txt - This file can be opened with the free, and research oriented, Kubios HRV software http://kubios.uku.fi/. This file is also a simple, plain text, listing of each measured heart beat. Each line of the file contains a single inter-beat interval in seconds. For example 1.0 would be 1 second between beats, make the instantaneous heart rate for that beat 60 beats per minute.
[session].bvp - The raw BVP data in case you want to calculate your own heart rate. The BVP data is only available from the device at a rate of 30 samples per second. Assuming a best case scenario, with a 30 sample per second rate, you would normally see up to a 2 beat per minute error margin on a 60 bpm heart rate, but we have mostly eliminated this through complex analysis of the incoming bvp signal. Therefore, if you want to determine your own heart rate using this BVP file, you should try to achieve at least as accurate a sampling as we do, and perhaps compare it to an EEG. Overall, if you need a perfect, error free measure of heart rate during Alive training, I suggest you also record heart rate using an EEG, separately, so you can analyze the effects of training with Alive and/or compare the results to the heart rate shown on screen. We have gotten a very high correlation with measured EEG signals ( ~0.5 bpm variation, and with an almost identical shape, leading to an assumed negligible difference in the HRV ).
[session].scl - The raw SCL data, sampled at 30 samples per second. I know that some more clinically oriented SCL devices can see smaller changes in SCL than the IOM (or Lightstone) can provide, but for most people the SCL values are well within a useful training range, and you will see good SCL spikes when introducing stressors. You could contact the Wild Divine for more information, but also check the SCL display in Alive itself ( or the free Alive Clinical User Guide at http://www.somaticvision.com/downloads/ ... -Guide.pdf). SCL is displayed at a precision of 0.01 uSiemens.
[session].csv - These files are not the best for research. These are good for creating quick graphs of sessions in Excel, but only contain data sampled at 3 samples per second (although for heart rate that may be fine).
If you are studying HRV you can use Kubios to analyze frequencies over various time periods in the Alive session files. Alive does do frequency analysis, as you can see in the advanced graphing screen, but our determination of HRV, which we call smoothness, is not identical to what Kubios will do, as Alive is designed to respond extremely quickly, based on the idea that if what you do doesn't show on screen for 20-30 seconds people have a hard time linking their positive changes with the results seen on screen (as can happen if training HRV with HeartMath or other competing professional HRV algorithms). Alive's algorithms are designed to respond in 3-10 seconds, and sometimes after a single beat. Therefore Alive's analysis provides for a much more effective reward mechanism, and with generally more useful data for the user. Nevertheless, if you analyze HRV using Kubios or another method, you should see a strong spike around .1Hz (or their dominant frequency and/or breathing rate) during the times Alive shows smooth (or slightly after I suppose).
Most research studies done using Alive so far are done to test Alive's effectiveness for a certain conditions (PTSD, gastric distress, stress-related issues, optimal performance in stressful conditions). I have a list of researchers who are interested in talking with other researchers about Alive, if you would like to be contacted by them. If so, please send me an e-mail using the contact form on the support page, or private message me.
I hope this explanation of using Alive for research helps. Alive is a truly unique piece of software, and has many practical and theoretical uses, which are prime topics for research.
Best,
Ryan Deluz
Somatic Vision Inc.
* The statements on this post have not been evaluated by the FDA. Alive is not intended for use as a treatment tool for depression or other medical conditions. If you are experiencing depression, you should seek advice and treatment from a medical professional.
I'm not sure if anything is published yet, but there are a number of studies (those which I specifically know of are government funded) in progress using Alive, Dual Drive, and the Half Life 2 BioMod for Alive.
Alive is designed mainly for training of HRV and SCL. To analyze HRV and SCL using standard tools is possible, as all SCL and BVP (blood volume pulse, which determines heartrate) as well as heart rate measurements are stored in files external to Alive. I will assume you are using an IOM sensor, but the emWave sensor should be similar in most cases.
In your Documents/Alive Sessions/[user name] folder you will see the following files for each recorded session:
[session] kubios.txt - This file can be opened with the free, and research oriented, Kubios HRV software http://kubios.uku.fi/. This file is also a simple, plain text, listing of each measured heart beat. Each line of the file contains a single inter-beat interval in seconds. For example 1.0 would be 1 second between beats, make the instantaneous heart rate for that beat 60 beats per minute.
[session].bvp - The raw BVP data in case you want to calculate your own heart rate. The BVP data is only available from the device at a rate of 30 samples per second. Assuming a best case scenario, with a 30 sample per second rate, you would normally see up to a 2 beat per minute error margin on a 60 bpm heart rate, but we have mostly eliminated this through complex analysis of the incoming bvp signal. Therefore, if you want to determine your own heart rate using this BVP file, you should try to achieve at least as accurate a sampling as we do, and perhaps compare it to an EEG. Overall, if you need a perfect, error free measure of heart rate during Alive training, I suggest you also record heart rate using an EEG, separately, so you can analyze the effects of training with Alive and/or compare the results to the heart rate shown on screen. We have gotten a very high correlation with measured EEG signals ( ~0.5 bpm variation, and with an almost identical shape, leading to an assumed negligible difference in the HRV ).
[session].scl - The raw SCL data, sampled at 30 samples per second. I know that some more clinically oriented SCL devices can see smaller changes in SCL than the IOM (or Lightstone) can provide, but for most people the SCL values are well within a useful training range, and you will see good SCL spikes when introducing stressors. You could contact the Wild Divine for more information, but also check the SCL display in Alive itself ( or the free Alive Clinical User Guide at http://www.somaticvision.com/downloads/ ... -Guide.pdf). SCL is displayed at a precision of 0.01 uSiemens.
[session].csv - These files are not the best for research. These are good for creating quick graphs of sessions in Excel, but only contain data sampled at 3 samples per second (although for heart rate that may be fine).
If you are studying HRV you can use Kubios to analyze frequencies over various time periods in the Alive session files. Alive does do frequency analysis, as you can see in the advanced graphing screen, but our determination of HRV, which we call smoothness, is not identical to what Kubios will do, as Alive is designed to respond extremely quickly, based on the idea that if what you do doesn't show on screen for 20-30 seconds people have a hard time linking their positive changes with the results seen on screen (as can happen if training HRV with HeartMath or other competing professional HRV algorithms). Alive's algorithms are designed to respond in 3-10 seconds, and sometimes after a single beat. Therefore Alive's analysis provides for a much more effective reward mechanism, and with generally more useful data for the user. Nevertheless, if you analyze HRV using Kubios or another method, you should see a strong spike around .1Hz (or their dominant frequency and/or breathing rate) during the times Alive shows smooth (or slightly after I suppose).
Most research studies done using Alive so far are done to test Alive's effectiveness for a certain conditions (PTSD, gastric distress, stress-related issues, optimal performance in stressful conditions). I have a list of researchers who are interested in talking with other researchers about Alive, if you would like to be contacted by them. If so, please send me an e-mail using the contact form on the support page, or private message me.
I hope this explanation of using Alive for research helps. Alive is a truly unique piece of software, and has many practical and theoretical uses, which are prime topics for research.
Best,
Ryan Deluz
Somatic Vision Inc.
* The statements on this post have not been evaluated by the FDA. Alive is not intended for use as a treatment tool for depression or other medical conditions. If you are experiencing depression, you should seek advice and treatment from a medical professional.
Re: Research with Alive
Thank you for your comprehensive response!