EMG, GSR & Skin Temperature Application User Guide

Contents

1. Introduction & launching the application
2. Parameters
3. Working with the EMG, GSR & ST Application (User Interface)
4. Audio Feedback
5. Breath Counting Functionality
6. Report Functionality

Introduction

This guide introduces the EMG, GSR and Skin Temperature biofeedback application, part of the Mind-Body Training Tools suite. MBTT applications are designed to train self-regulation skills, which I sometimes call mind-body skills.

This guide aims to teach you how to use the software, and to some extent how to work with each of the three biofeedback parameters, however it doesn't go as far as teaching the practitioner how to use this application with clients for the development of self-regulation skills. For that, I refer you to the Biofeedback Practitioner Training Course.

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.

The application works with three parameters together. Using all three at once gives a fuller picture of the way the mind-body connection is playing out, at the price of greater complexity. Each of the parameters has its own “basic” application in Mind-Body Training Tools, and my recommendation is that new practitioners gain familiarity with each parameter separately first, before working with the combination app.

The three parameters relate to stress, but each gives a somewhat different view of the stress response. Skin Conductance (SC) and Skin Temperature (ST) changes are both mediated by Sympathetic Nervous System activation, but each shows a different time scale.

Launching The Application

To launch the application (after starting the platform program) first click on the "EMG & Peripheral" tab, then select the "EMG, GSR & Skin Temperature" application from the drop-down list, then click the button to launch the app.

Parameters

As stated, the app works with three input parameters, which are also feedback parameters:

• EMG, an electrical correlate of muscle tension - read more about EMG and its use in biofeedback training here.
• Skin Conductance - an electrical parameter that represents GSR, described in more detail in this Guide to GSR biofeedback.
• Skin Temperature - its use in biofeedback is described in this user guide.

Working With The EMG, GSR & Skin Temperature 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:

1. Main window, or trainer's window, containing parameter charts
2. Threshold window - each app has at least one threshold, but there are usually more.
3. 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.

The main window, shown here, follows the normal MBTT pattern of short term displays in the upper half, and a longer term trend chart in the lower.

TO_DO This video gives a tour of the EMG, GSR and Skin Temperature app.

Threshold Controls

The threshold window for the EMG, GSR and Skin Temperature app is shown here:

There are three thresholds, one for each parameter. Notice that the GSR and ST thresholds are both based on rate of change rather than the parameter itself. (This makes sense because we're interested in relative change more than actual values.)

You can learn more about how thresholds operate in Mind-Body Training Tools in this guide.

Audio Feedback

The application offers midi feedback, tone feedback, and threshold-based contingent audio feedback. Additionally, you can transmit feedback parameters out of BioEra, for use with external feedback applications, such as the “Shadow” Feedback Utility (which is part of the Platform program).

Threshold-based audio feedback means that you can play a sound whenever the signal crosses one of the threshold levels. The controls for threshold-based audio feedback are found at the bottom of the threshold - there is a start / stop button, there is a volume slider, and you can configure which events trigger feedback (e.g. going above the upper level).

The controls for other forms audio feedback are found in a separate window shown below:

In midi feedback, a musical note is played whose pitch varies with the selected feedback parameter. Again you can opt to invert the pitch mapping.

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 score produces a lower tone.

Tone feedback works in the same way as midi feedback, except that a simple, constant tone is played in place of midi notes. Tone feedback could be said to have greater sensitivity, since the pitch varies continuously rather than being restricted to musical pitches (A, B, C# etc.) as midi feedback does.

Auto-Range Feature

Both midi and tone feedback have an auto-range feature, meaning they work in a similar way to trend charts. When the signal moves above or below the chart range, the chart resets so that the signal is in the middle again. The scale is maintained but the range shifts up or down.

In a similar way, if audio feedback pitch moves to the limit of the pitch range, the sound resets so that the pitch is in the middle of the range again (and the same scale is maintained).

Audio feedback is demonstrated in the following video TO_DO.

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 GSR Basic.

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. This figure shows the report options for EMG but it's almost the same for GSR:

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:

Sample Session Report from the EMG, GSR and Skin Temperature application

Sample Application Report (not from the EMG, GSR & ST application).