EMG & Breathing Application User Guide
Contents
- Introduction & launching the application
- Parameters
- Working with the EMG & Breathing Application (User Interface)
- Breath Counting Functionality
- Report Functionality
Introduction
This guide introduces the EMG & Breathing biofeedback application, part of the Mind-Body Training Tools suite.
The application is designed to train a subset of optimal breathing skills. Optimal breathing is a widely applicable skill-set, for example it's very relevant to stress management and peak performance. The app tracks muscle tension (via an electrical correlate, EMG) in relation to breathing. The use of EMG in this way allows us to differentiate two key patterns of breathing: chest-based breathing and abdominal breathing.
By siting the EMG sensors at the wrists, we can pick up on muscle activity in the shoulders and upper chest over the breath cycle. Abdominal breathing doesn't really register, with the wrist placement.
Learning to breath slowly, steadily and abdominally is a key part of optimal breathing training.
The guide has two purposes: firstly to explain what is being measured (and how), and secondly to teach you how to use the software. How to use the biofeedback in the context of coaching or therapy is beyond the scope, and I refer you to my Biofeedback Practitioner Training Programme.
Besides EMG, the application monitors breathing via either temperature of inhaled / exhaled air, or breathing movements in the body using a strain gauge around the chest or abdomen. From either input the software can calculate breathing rate and other parameters.
The guide assumes that you already have a basic knowledge of how to work with Mind-Body Training Tools software. If not, I suggest you read this Introductory Guide to Working with MBTT.
Launching The Application
To launch the application (after starting the platform program) first click on the "EMG & Peripheral" tab, then select the "EMG & Breathing" application from the drop-down list, then click the button to launch the app.
Parameters
Input Parameters
There are two input parameters, first EMG, and second, a breath parameter. Technical aspects of EMG and its measurement are given in this user guide. Breath can be measured by one of two sensors:
- Temperature probe - when placed at the nostril, a temperature probe can detect the temperature difference between inhaled and exhaled air.
- Belt or strain gauge sensor - when placed around the chest or abdomen this detects breathing movements which stretch the belt.
You can read more about breathing measurement in MBTT in this guide.
Feedback Parameters
From the two input signals, the application calculates the following parameters which are used for feedback:
- Minimum EMG per breath cycle
- Maximum EMG per breath cycle
- Chest score - being the difference between the maximum and minimum EMG per breath cycle, it gives a rough estimate of the extent of chest-based breathing (as opposed to abdominal breathing) assuming that the EMG sensors are suitably placed to detect breathing muscles involved in chest-based breathing.
- Breathing Rate in breaths per minute
- Ratio of inhalation time to exhalation time, or simply I:E ratio.
Working With The EMG & Breathing Application (User Interface)
The MBTT apps have a common design scheme. The intent is that learning to use one app, can be generalised so that other apps in the suite are easy to learn.
The apps generally have three windows:
- Main window, or trainer's window, containing parameter charts
- Threshold window - each app has at least one threshold, but there are usually more.
- Feedback window - in a sense, all charts and thresholds are giving feedback, but the feedback window contains controls for audio feedback plus more specialised feedback forms.
Main Window
The main screen looks like this:
TO_DO
Threshold Controls
In biofeedback, physiological parameters are mapped into visual or auditory form, so that the trainee can perceive changes directly through his senses. Feedback can be continuous and proportional to the parameter, or it can be discrete and dichotomous, for example a bell sounds whenever breathing rate rises above some limit.
Thresholds are the means of configuring the mapping, meaning they define how much of the parameter results in how much feedback.
The principles of thresholding and feedback are described in greater detail in this guide.
The EMG & Breathing app has four thresholds, shown below.
All these thresholds offer automatic calculation of threshold levels based on criteria you set.
Audio Feedback
The application offers midi feedback and threshold-based contingent audio feedback. Additionally, you can transmit feedback parameters out of BioEra, for use with external feedback applications. In particular you can use the Breath Player utility, which is part of the MBTT Platform program.
Threshold-Based Audio Feedback
To recap, the basic concept is that the software plays a sound (actually a midi note) whenever a threshold limit (level) is crossed.
The controls for threshold based feedback are found at the bottom of the threshold controls. There is a button to activate it / turn it off. A drop-down control sets the condition or contingency: for example if set to “above”, the feedback will sound whenever the parameter exceeds the upper level. “Below” means it sounds below the lower level, and “outside” means it sounds for either of these two.
You can change the midi “instrument”, and you can have the sound repeat for each breath that meets the threshold condition, or only the first time the level is crossed.
Audio Feedback Window
The controls for audio feedback, aside from the threshold-based audio feedback discussed above, are found in a separate window shown below:
In midi feedback, a musical note is played whose pitch varies with the selected feedback parameter. You can select which parameter to use as the basis of feedback using a drop-down list control, and you can invert the pitch mapping if you wish, so that a higher reading produces a lower tone.
Breathing Tone Feedback
Breathing tone is a particularly powerful feedback modality if you want to train with biofeedback in a more meditative context, or during mindfulness practice.
In breathing tone biofeedback, a tone is played which follows the breath. The pitch gently ascends and descends in pitch for each inhalation / exhalation respectively. (Each breath has a relatively narrow range in pitch.) The tone sounds during the movement of the breath, and falls silent at the turning points.
At an overarching level, the pitch varies with the selected feedback parameter. For example, you can set the breathing tone feedback to track breathing rate. If your breathing speeds up (perhaps when you've become distracted) the tone will rise in pitch.
MBTT's breathing tone feedback feature is part of the Platform program. To use it you have to transmit data out of the BioEra app (by clicking on the External Feedback ‘Play’ button in the above audio feedback window). For more details on how to work with breathing tone feedback, see this guide on the MBTT Breath Player Utility.
Audio feedback is demonstrated in the following video TO_DO.
Breath Counting Functionality
In keeping with other applications which measure breath, the heart coherence app offers breath counting functionality. This is useful in a context of meditation practice (with breath as the object of focus) where the meditator counts breaths up to a target of say, ten. Distraction and mind-wandering cause the meditator to lose count, and perhaps to lose awareness of the breath completely. The user presses the space bar to start a count, and then again when the target is reached. The software tracks the breath count too, but is not prone to distraction, and thus can judge the meditator's performance.
Breath counting functionality is discussed in more depth in the Guide to Working with MBTT Apps.
Report Functionality
Mind-Body Training Tools allows you to generate session reports and application reports.
The controls for report generation are found in the platform window, in the EMG & Peripheral tab shown towards the beginning of this document. You need to have selected the right application from the drop-down list - in this case Basic Breathing.
A session report shows charts and tables for the feedback parameters summarising the whole session. You'll be asked to select one particular session, and given report options. The options dialog looks like this:
The application report shows the variation of the feedback parameters across multiple sessions. Typically for each feedback parameter, the software generates line charts for session means, session maxima and session minima.
Report functionality is described in greater depth here.
You can see sample reports here (but note neither is from the EMG & breathing app):
Sample Application Report (Heart Coherence app)