EEG Assessment User Guide
Contents
1. Sites Theta Alpha Beta Hi Beta T B Fz Oz EC 458 6 1 4 5 40 7 52 4 Fz Oz EO 81 9 10 3 16 9 55 8 112 7 Fz Oz Band Amplitudes EC Fz EN Oz tie Fz SD tie Oz SD Z I Delta Alpha High Beta F B Coherence Data Sites Delta Theta Alpha Beta Hi Beta Fz Oz EC 0 43 0 33 0 42 0 19 0 16 Fz Oz EO 0 46 0 37 0 35 0 18 0 22 Fz Oz Band Amplitudes EO EN Fz Ye Fz SD 27 Oz SD Delta Alpha High Beta Frontal Midline Analysis High Beta to Beta Ratio Site EC EO Chal Fz 0 67 0 83 0 00 F3 0 89 0 00 0 00 F4 0 93 0 00 0 00 Site Comparisons Sites Theta Alpha Beta Hi Beta T B Fz F3 EC 22 2 26 1 21 0 9 9 1 0 Fz F4 EC 24 7 23 8 22 8 12 1 1 5 Appendix B Sample Site Analysis Report Client s name Smith John Assessment date 21 06 2012 15 38 59 Protocol EO EC EO Challenge Bands Data 1 Theta 3 0 uV 2 8 uv 2 8 uv 3 2 uv 1 Chal 1 6 uv 3 2 WV Alpha 2 0 uV 2 6 uV 1 9 uv 1 2 UV 0 8 uv 1 1 uW 0 8 uv 5 UV 11 6 uV 11 6 uv 4 uV 11 1 uV 11 2 uv Slow Alpha Fast Alpha 0 8 uv 0 8 uv 0 7 uv 0 8 uv Beta 1 2 uV 1 0 uv 1 1 uv Lo Beta 0 9 uv 0 8 uv 10 9 uv 10 8 uv Hi Beta 1 1 uV 1 0 uv Band Amplitudes by Condition 3 5 EO Zu EOSD 3 Na EC tit ECSD 2 5 EN CC Z tit CCSD s 2 3 15 L 1 0 5 0 Theta SMR High Beta Deka Alpha Beta2. FAR RN KI edt eee AO S D Color On Off E L ES 0 3 9 7 8 Figure 10 BioEra Review application This session was recorded using the EO EC EO assessment protocol You can see from the upper Assessment Stages chart that there were three phases Note that unlike the text summary file the session file does not include artefact information all eye blinks movements etc that happened during the recording will be present in this data It s not possible to exclude artefacts The main chart shows up to four traces representing the major frequency bands delta theta alpha and beta You can select which of these are visible by checking unchecking the boxes in the final column of the table below the main chart In figure 10 the delta trace 1s not displayed You can see in figure 10 that the green alpha trace increases significantly during the eyes closed phase of the assessment There are two combo box controls at the top which control the appearance of the traces The first one sets the number of data points drawn Choosing a higher value means fewer points Note that epoch in this context has a different meaning from earlier sections The second control sets the level of averaging and hence how smooth the trace looks Select a longer average for a smoother trace or a shorter average for a more fine grained view You can zoom in on a portion of the session by clicking and dragging your mo
3. Select the sites you re recording from You can also test impedance of your sensor connections 1f you re using an amplifier hardware device that supports software measurement before staring the recording application This 1s a useful quality assurance step Press the button Run BioEra Impedance Check App As its label suggests a BioEra application 1s started Finally when you re ready to begin press the button Record New EEG Data This opens one of the BioEra data recording applications described in detail in section 4 below 2 2 1 Assessment Protocol The assessment protocol encodes the sequence of conditions under which EEG is recorded The table below lists the protocols available Protocol Seguence EC only The simplest seguence the condition is Eyes Closed EC throughout EO EC EO 3 phases Eyes Open EO followed by Eyes Closed followed by Eyes Open again EO EC EO 4 phases Eyes Open followed by Eyes Closed followed by Eyes Open again Challenge followed by a period for challenge or task the assessment subject will perform some task typically a cognitive task such as reading and typically with eyes open Baseline A baseline period followed by a challenge or task Typically the task will be a Challenge cognitive challenge such as a working memory exercise Mostly you would probably want to run the protocol with eyes closed throughout but you can also use it with eyes open The protoco
4. suppose you choose to filter based on the delta band 1 e you check control 5 Now whenever the delta amplitude goes above the threshold represented as the dotted yellow lines in the upper display of figure 8 the current sub epoch will be marked as containing artefact You can set the level of this threshold by dragging the level shown in the bar graph display at the left labelled 1 in figure 8 with your mouse You ll see the dotted yellow lines update Note the two are mirror images of each other either side of zero You may need to change the scale of the displays doing so will update the threshold levels You can do this using the combo box control 7 in figure 8 The second filter 70 90 Hz for muscle artefact has controls that work in exactly the same way I suggest you take time before you start recording 1 e after pressing play but before pressing Start to observe the trace and make sure you have set the thresholds to a suitable levels Have your assessment subject deliberately produce artefacts such as eye blinks and swallows so that you can make a judgement You can change the settings of the filters used for artefact detection by pressing the Filter buttons 8 for the delta filter and 12 for the EMG filter in figure 8 For example you may wish to adjust the freguency ranges 5 2 Artefact Detection in the 2 and 4 Channel Applications In the 2 and 4 channel applications only one set of artefact detection displays a
5. Dominant Frequencies Data Band Ec Je ena Dominant Frequencies by Condition EO ee EOSD Beta EN EC wii ECSD Alpha EN CC Yee CCSD Overall 0 5 10 15 20 25 Dominant Frequency in Hz Ratios Ratio Meme ec eo Jena ite seta 0 09 oss 097 ie Significant Changes Theta EO to CC Beta EO to CC Theta to Beta EO to EC 10 2 Theta to Beta EO to CC 9 4 Alpha Response EO to EC 32 8 Alpha Blocking EC to EO2 40 8 Dom Freq EO to EC 1 6 Hz Band Amplitudes Over Time Theta Alpha Beta Amplitude in uV 0 20 40 60 80 100 120 140 Session Time in Seconds Epochs Data Slow Fast Lo Alpha EO 1 70 uv 2 96 uV 1 88 uV 1 07 uv 0 60 uv 1 10 uV 0 78 uv 1 03 uV 3 6 Hz 9 1Hz 119 2 Hz FANE EO 1 1 43 uV 2 65 uv 1 99 uv 1 07 uv 0 80 uv 0 96 uv 0 93 uv 10 96 uv 18 8 Hz 1 49 uV 2 84 uV 2 57 uV 1 38 uv 0 82 uv 1 16 uv 10 84 uv 1 11 uv 20 0 Hz s je res w aaa uv 190 u 122 w ase w uotu o 70 0v i10 w 2 90 9362 Joar Coherence Data Sites Cz Fz Band tc to Jena ses Ja kale Band Coherences by Condition 1 EO EN EC EN CC 0 8 8 06 S L O 04 0 2 0 Delta Theta Alpha Beta High Beta EEG Assessment User Guide copyright Glyn Blackett page 27 Appendix C Sample Sites Comparison Report Assessment date 21 06 2012 15 14 44 21 06 2012 15 14 44 Bands Data EC 2 1 7 F3 F4 Ba
6. box represents a folder Base Folder Client 1 Client 2 Protocols EEG Training EEG Assessments EEG Training BEE 07 Assessment Date1 Assessment Date2 Figure 5 Application data folder tree Running the BioEra EEG data recording application generates two data files per channel the site data summary file in text format txt and the BioEra session file edf The latter is read by the BioEra review application which 1s covered in section 6 4 below The site data summary file 1s used to generate reports sections 6 1 to 6 3 It contains amplitude dominant freguency and when more than one channel of EEG is recorded coherence data This section takes a closer look at the data file which will be helpful in understanding how the reports are derived 3 1 Epochs and Sub epochs The summary data file text format contains EEG data structured in terms of epochs and sub epochs An epoch 1s simply a fixed time period e g 20 seconds Each site assessment consists of several epochs one or more per condition EC EO etc You can set the epoch length You can set it independently for each recording but I recommend you keep the same setting for all recordings in your assessment as it can affect some sections of the assessment report A sub epoch is simply a 1 second long subdivision of an epoch The purpose of dividing the r
7. overwritten Use this option if you change your mind on the other report options Add notes to report When checked the software allows you to type some comments about the report Mark data points The report contains line charts showing the main band amplitudes over time The lines connect data points one per sub epoch Checking this option means a dot is drawn for each data point Vertical axis from zero Not including zero on the vertical axis gives a more sensitive range but may in some way misrepresent the variability of the data Include coherence data When checked a chart and a table showing band coherence data is included if it is available it s only recorded by the 2 and 4 channel applications Show variability data When checked the software calculates standard deviations of all the main data parameters e g band amplitudes These are displayed as extra bars in the bar charts e g the standard deviation of the alpha amplitude is shown as a hatched bar above the main alpha amplitude bar Of course the real variation 1s above and below the mean but it 1s only shown above Showing variability data gives you a sense of how stable the brain state is ranging from chaotic to rigid The calculation is based on the 1 second long sub epoch amplitudes recorded in the site text summary file Text only When checked charts are excluded making a printer friendly report Bar
8. 8 0 00 Alpha Response Alpha should quickly rise on closing eyes most prominently at the back of the head gt 50 then drop down again when the eyes open Site Response Blocking Oz 121 7 120 0 Amplitude in uV Alpha Speed Alpha speed is a measure of brain efficiency and correlates with intelligence Optimal alpha dominant frequency is 10Hz and above Alpha Response Blocking by Site Session Time in Seconds Site DF EC DF EO Ratio EC Ratio EO Fz 9 5 Hz 9 0 Hz 1 31 1 23 F3 9 3 Hz 0 0 Hz 2 05 0 00 F4 9 3 Hz 0 0 Hz 1 88 0 00 Oz 10 1 Hz 10 0 Hz 1 18 1 06 Theta Alpha Ratio Site EC EO Chal Fz 0 84 2 28 0 00 F3 0 87 0 00 0 00 F4 0 84 0 00 0 00 Oz 0 54 1 38 0 00 Left Right Balance Optimal brain state theta alpha and beta are within 10 Imbalances may correlate to emotional problems Sites Theta Alpha Beta Hi Beta T B F3 F4 EC 2 0 1 9 1 5 2 1 0 5 Oz F3 F4 Band Amplitudes EC F3 EN F4 ZLF3SD ZG F4 SD E L R Coherence Data Sites Delta Theta Alpha Beta Hi Beta F3 F4 EC 0 42 0 31 0 41 0 17 0 18 Front Back Balance Optimal brain state more alpha at the back especially in EC condition and more beta in the front Reversals may correlate with weak executive function
9. 9 0 74768066 1 0681152 0 8239746 1 4343262 0 8087158 9 549738 9 549738 2 0 1 2054443 2 670288 7 7209473 1 2207031 1 7242432 0 88500977 1 5258789 1 1749268 9 549738 9 549738 2 0 1 3580322 1 7242432 4 9591064 1 7700195 1 159668 1 2054443 1 2359619 1 0375977 9 549738 9 549738 2 0 1 5258789 2 243042 4 0130615 2 2583008 2 822876 0 74768066 1 3427734 0 8392334 9 549738 9 549738 2 0 1 8463135 3 0517578 4 4555664 0 8239746 1 373291 0 91552734 1 4190674 0 76293945 10 052356 10 052356 2 0 1 5106201 3 5247803 3 7078857 1 0223389 1 5716553 0 61035156 1 2969971 0 8392334 9 549738 9 801046 2 0 1 0375977 2 532959 3 5552979 1 1138916 0 869751 1 1901855 1 2054443 1 0681152 7 2879577 9 298429 2 0 1 0223389 2 7313232 4 547119 1 2207031 0 76293945 1 1749268 1 1291504 0 88500977 9 549738 9 549738 2 0 1 3122559 2 5177002 3 40271 1 2817383 0 8544922 0 8087158 1 2817383 0 88500977 9 549738 9 549738 2 0 1 6021729 3 6468506 3 4942627 1 083374 1 0223389 0 47302246 1 9073486 1 0223389 9 549738 9 549738 2 0 00000000000 QC 4D CO 3 mum EL KM F2 OD Jm 04 Co MN P O 0000000000000000000050 Sno oF 8 eee aj Oooccocooococs CO OO OO OO OO OO OO OO OO OO OO CO O0 QO OO OO 0 O OO OO O OO OO o oco KA K KM KM KM M KM KM KM GG 50000000000 0 0 1 2 3 E 5 6 7 8 9 h 1 1 1 1 1 1 1 1 1 2 2 2 2 2 2 2 2 2 2 3 NN KM KM KM KM KM KM M M KM KM KM KM PO KA MA KA KA KA LA CO O0 QOO O QO 0 0 0 0 O O O 0 O O O O OO o o Figure 6 The site t
10. 9 801046 9 801046 2 0 1 9226074 2 2735596 4 180908 0 5645752 1 2207031 0 5950928 1 5411377 0 77819824 10 052356 10 052356 2 0 2 1362305 2 380371 5 508423 1 0528564 0 88500977 0 579834 1 6021729 0 77819824 9 801046 9 801046 2 0 1 0223389 2 5024414 7 598877 0 36621094 1 663208 0 7324219 1 6326904 0 90026855 10 052356 10 052356 2 0 2 4261475 3 6010742 3 9367676 1 7089844 1 1138916 0 5187988 1 3427734 1 0986328 10 052356 10 052356 2 0 1 3122559 2 9144287 5 9661865 0 93078613 1 3580322 0 579834 0 9918213 0 91552734 9 801046 9 801046 2 0 2 1820068 3 5095215 3 1433105 0 9918213 0 869751 0 79345703 1 4801025 1 0070801 9 801046 9 549738 2 0 1 4648438 2 4871826 2 8381348 0 90026855 0 5493164 1 0681152 1 3885498 1 1138916 4 272251 9 549738 2 0 1 1901855 2 8076172 4 333496 0 79345703 0 44250488 0 64086914 1 1444092 0 93078613 7 0366488 9 801046 2 0 1 3275146 3 3569336 2 822876 1 8920898 0 47302246 0 8544922 1 0681152 0 90026855 9 549738 9 549738 2 0 2 1362305 1 9683838 3 9978027 0 93078613 0 64086914 0 47302246 1 1291504 0 8392334 8 041884 9 549738 2 0 1 663208 2 9449463 5 5999756 1 9073486 1 2359619 1 0070801 1 6021729 1 0375977 9 801046 9 801046 2 0 1 953125 3 112793 5 554199 1 4648438 1 4190674 0 869751 1 2207031 0 90026855 9 549738 9 549738 2 0 1 5411377 3 036499 3 4332275 0 77819824 1 9836426 0 61035156 1 6021729 0 9613037 9 549738 9 549738 2 0 1 1901855 2 166748 4 1656494 1 0681152 1 4343262 0 9918213 1 3580322 0 869751 9 04712 9 04712 2 0 1 1138916 1 6479492 5 55419
11. YORK BIOFEEDBACK www york biofeedback co uk O Glyn Blackett EEG Assessment User Guide Table of Contents TICO mmm m m m e aos 2 1 1 Overview of the EEG Assessment Hrocess aaa aaa aaa aaa esee 2 2 Running an Assessment aaa aaa aaa aaa kaaa kakaa sese aaa 4 EA le ef METE rr ote iii ate E aa I PRENNE 5 2 2 Recording New Assessment Data 6 2 2 1 Assessment Hroiocol aaa kaaa aaa kaaa kakaa aa eme aaa aaa ns T 3 Overview of the Assessment Data 8 21 TE DOGS and ET PO somme dara uad uta u cta kak aid ba go a a VE S 8 3 2 Site Data File Naming kaaa aaa aaa kaaa aaa nnn 9 3 3 The Site Data File in Detail aaa anna aa aaa aaa aaa I 9 3 4 Editing The Site Name aaa 9 4 The BioEra EEG Data Recording Appicaton aaa aka kaaa aa akan anno 11 ow Miji Mema PP mmen mere mem npr meme 13 5 1 Threshold Based Artefact Detection eene 13 5 2 Artefact Detection in the 2 and 4 Channel Applications 14 6 Data Analysis and Report Generaion aka akan kakaa aka kaaa kaaa a 15 6 1 The Assessment NEDOV ri 15 ALT Repo ie le 16 6 1 2 Site Dfferences aaa aa aa aaa aaa aaa IR RR aaa aaa aaa aaa aaa 17 6 2 The Site Analysis Report nana 17 Spremi Mae slej ll e e AI Ra ena 17 6 3 The Sites Comparison Reno 17 Se Biz ole E ra ESEE NEEE 18 6 4 The BioEra Review Applcaton kakaa aaa aaa aaa aaa 18 Appendix A Sample Assessment Rep
12. ation described in the previous section has displays and associated controls to assist with artefact rejection These are labelled 10 and 11 in figure 7 and are reproduced in figure 8 below 0 5 1 1 5 2 2 5 3 3 5 4 4 5 2 2 5 3 6 5 Raw Signal Range 80 uv X v Period 108 v Apply delta filter MU Delta Range Filter Y Apply EMG filter EMG Range 30 uv A 3 4 5 6 T 8 9 10 Figure 8 Artefact detection and rejection displays and controls The software uses two filters to help detect artefact These have the following freguency bands e delta 0 5 4 Hz eye movements and blinks show up here as do cable and electrode movements 70 90 Hz activity used to reflect muscle activity or EMG including swallowing The upper display of figure 8 shows the delta filtered EEG trace while the lower shows the EMG filtered trace Each 1s separately controllable The software marks artefacts automatically based on threshold settings which you can control 5 1 Threshold Based Artefact Detection Sub epochs are marked as artefact containing when the amplitude from either of the artefact filters described above exceeds a threshold Effective detection depends on setting these thresholds appropriately You can set these thresholds using the controls labelled 1 and 2 in figure 8 To apply automatic artefact detection you must check either or both of the check box controls 5 and 9 in figure 8 For example
13. ch essentially encodes a sequence of these conditions e g EC followed by EO followed by EC again The EEG data consists of band amplitudes dominant frequencies and for 2 or 4 channel recordings coherences Sections 2 2 and 4 cover recording of EEG data Once you ve recorded your EEG data you can analyse it by creating reports Reports are a way of summarising useful EEG patterns and markers such as the average amplitude in the theta band in the EC condition There are three report types 1 Assessment report this draws together data from all sites and 1s thus the most important 11 Single site report offers a more detailed look at data from a single site 111 Sites comparison report offers a side by side view of any two sites for comparison All the reports cover the main frequency bands delta theta alpha beta etc significant ratios such as theta to beta and compare different conditions e g EC vs EO Most users will only need the first overall assessment report Reports are created in html format and are opened for viewing in your computer s default web browser Section 6 covers report generation The software can exclude artefact from the analysis Artefact is a component of the measured signal that does not originate from the brain example sources of artefact are eye blinks and muscle tension The software has tools to allow you to mark sections of the data which contain artefact These section
14. d For the fairest comparison your two site data files will have been generated at the same time using the 2 or 4 channel version of the BioEra data recording application however the software doesn t impose this constraint Once you ve selected your two site data files you ll see a report options dialog window appear the same as for the assessment and site analysis reports See section 6 1 1 above for details The report itself should be mostly self explanatory A sample is given in Appendix C of this document Where the difference between the two sites are reported as a percentage the calculation is a percentage of the smaller of the two site values 6 3 1 Report Files The report file is stored in your assessment folder A file name is generated by concatenating the two site data prefixes plus Comparison html e g F3 EC F4 EC Comparison html As with the other reports images are saved as separate files in the assessment folder in png format Again you can email the reports but don t forget to include the image files 6 4 The BioEra Review Application To view an assessment session file using the BioEra review application press the button labelled Step 3C in figure 1 You will be prompted to select a session file from within the currently selected assessment folder Figure 10 below shows a sample session review Ze BioEra 2 3 170 NF Review Assessment Stages Epoch FEES gt Averaging 3s Frequency Bands
15. e g Fz and Oz e Frontal midline analysis looking in particular at the Fz site and comparing it to adjacent sites This may say something about the functioning of the anterior cingulate gyrus In the front back and left right comparisons differences are expressed as percentages of the lower of the two compared site amplitudes The report file 1s created within the assessment folder and always has the name Assessment Report html Charts used in the report are stored separately as image files which are referenced from the html The image file names begin Assessment Report and are in png format You can send the reports by email to other people they only need a web browser to read them they don t need the York Biofeedback software but don t forget to include the image files The best way may be to add the html file and image file to a zipped folder and send that 6 1 1 Report Options Report options Overwrite existing report E Add notes to report Mark data points Vertical axis from zero 4 Include coherence data if available 4 Show variability data E Text only Bar graph bands Figure 9 Report options dialog The following table describes the report options Overwrite existing report The software first looks for an existing report and 1f it finds one it opens that If none 1s found a report is generated Checking this option means any existing report is
16. e report itself should be largely self explanatory A sample is given in Appendix B Significant changes are calculated between two states and expressed as a percentage of the preceding state e g if an EO to EC change 1s calculated the difference 1s expressed as a percentage of the EO amplitude 6 2 1 Report Files The report 1s stored as an html file a file name is created by adding Report html to the site data name e g Fz EC Report html This file is saved in your assessment folder As with the assessment report charts are stored separately as image files 1n the assessment folder in png format These image file names have the same prefix as the report name e g Fz EC Again you can email the reports but don t forget to include the image files 6 3 The Sites Comparison Report Pressing the button for Step 3B View Comparison Report will open a summary report in which EEG summary data from one site is compared to that of another site You ll be prompted to select two site data text files in succession on which to base the report You can compare any two site data files in your assessment even if they were recorded at different times and even if they were made using different assessment protocols The sites comparison report will be based on eyes closed EC data only If you used either a Baseline Challenge or a Baseline Stimulation protocol then the baseline data 1s used it is assumed to be eyes close
17. e reports The BioEra session file can be viewed in the BioEra Review application covered in section 6 4 below The BioEra shows only the progression of up to four main frequency bands over the course of the recording and artefact containing sub epochs are not excluded 6 1 The Assessment Report Pressing the button for Step 3 View Assessment Report will open a report based on all data all sites in the assessment Appendix A at the end of this document shows an example assessment report You ll be offered report options in a dialog window shown in figure 9 below and described in section 6 1 1 There are several sections of the report covering the major patterns and relationships In brief they are e Site bar graphs showing amplitude bars for the main frequencies one chart per each site in the assessment e Theta to beta ratios across all sites and under different conditions EC EO etc tabulated e Alpha response change in alpha on eyes closing and opening again Table and graphs included e Alpha speed looking at alpha dominant frequencies for different sites and conditions e Left right balance this section compares laterally symmetrical sites such as F3 and F4 or T3 and T4 The theta alpha and beta frequency bands are shown Tabulated data and bar graphs are included e Front back balance similar to the previous section but pairs of sites in the front and back of the head are compared
18. ecording into sub epochs 1s artefact exclusion Each sub epoch is marked as clean or containing artefact Artefact containing epochs are excluded from the calculations for report generation The software waits until 1t has a full complement of clean sub epochs If the epoch length 1s 20 seconds this means 20 clean sub epochs which may take longer than 20 seconds to collect Artefact detection and exclusion 1s covered in section 5 below A secondary purpose 1s that the sub epochs are used to calculate variability values standard deviations in the reports see section 6 below The number of epochs depends on the assessment protocol The following table details this Protocol Sequence EC only EC 3 epochs EO EC EO EO 2 epochs EC I epoch EO 1 epoch EO EC EO Challenge EO 2 epochs EC 1 epoch EO 1 epoch Challenge 3 epochs Baseline Challenge Baseline 2 epochs Challenge 3 epochs Baseline Stimulation Baseline 2 epochs Stimulation 3 epochs 3 2 Site Data File Naming The software creates a file name for your site data automatically based on the site and protocol An example would be Fz EOECEO txt clearly this data is recorded from site Fz using the EO EC EO protocol If you record twice from the same site using the same protocol the software appends a number e g Fz EOECEO 2 txt Please note if you do this the overall assessment report will only
19. erwise it shows red If you re using the simulator no lamp 1s displayed Display 9 shows the raw EEG trace in the 2 and 4 channel applications you ll see two and four such traces respectively The combo box controls labelled 17 amp 18 control the amplitude and time ranges respectively of this display To be precise the trace 1s not quite the raw signal frequencies above 40 and below 1 Hz have been filtered out During recording the trace colour flips between grey and white every time a clean sub epoch is completed When it doesn t change it means artefacts have been detected Displays 10 amp 11 show frequency filtered signals associated with artefact detection Artefact detection and its associated controls 1s covered in section 5 below The time range of these two displays 1s always the same as that of the raw signal display Combo box 3 sets the duration of epochs After you press Start the application proceeds through the sequence of phases depending on the assessment protocol you selected see section 2 2 1 above The condition for the phase at any point is reflected in the text shown in 5 figure 7 The transitions between phases are marked with a bell sound The numeric displays 6 and 7 mark progress in terms of time epochs and sub epochs The display labelled 12 in figure 7 shows a spectral analysis of the EEG signal based on Fourier transformation meaning that 1t shows the frequency make up of the signal Control 13 s
20. ets the vertical amplitude range for this display Note that Fourier transform data is not recorded Display 16 shows the progression of the main frequency band amplitudes over time 1 e delta theta alpha and beta as calculated by the frequency filters which involves different mathematics from Fourier analysis Controls 14 and 15 are associated with this display 14 setting the vertical range of the chart and 15 setting the level of averaging or smoothing of the traces over time 5 Artefact Rejection Artefact 1s a source of contamination in the data In other words a component of the measured signal 1s not originating from brain activity but some other source The most common sources of artefact are muscle activity eye movement electrode and cable movement and external electric fields such as electric devices or the mains Clearly it 1s best to exclude artefact as far as possible from the analysis This guide does not cover all aspects of artefact control but confines itself to discussing how the software can exclude artefacts For practical purposes we are referring to intermittent artefacts namely movement eye movement and muscle activity EMG As explained in section 3 1 above epochs are subdivided into sub epochs for the purpose of artefact control Essentially sub epochs can be marked as containing artefact and so doing means the software will ignore them when generating reports The BioEra EEG Data Recording applic
21. ext data file opened using Wordpad EEG Assessment User Guide copyright Glyn Blackett page 10 4 The BioEra EEG Data Recording Application This section describes the BioEra application used to record EEG data Section 2 told you how to launch 1t In fact there are three versions of this application offering one two and four channel EEG recording Figure 7 below shows the user interface 1 channel version TENTE CE J OF site Fz 1 2 3 4 5 6 T EE Epoch 208 Start Press start to begin recording 00 00 Device C2 y Raw Signal Range 80uv ei Period jos V Apply delta filter FU Delta Range 30uv e Filter V Apply EMG filter PI EMG Range 10 2 uY sl Filter U 7 5 5 23 30 38 45 53 60 Bands Display Average T 8 y Range 110 i m FFT Range su y uM 13 Figure 7 BioEra EEG Data Recording application interface Pressing the Play button labelled 1 in figure 7 initiates the flow of data from your amplifier or the simulator to the application but it does not start recording To begin recording data press the Start button 4 in figure 7 Before pressing Start you can configure the displays and controls instruct the assessment subject and otherwise prepare for the actual recording On pressing Play the device status indicator 8 in figure 7 updates to reflect the current status of your amplifier If the amplifier is connected and working properly the light shows green as in figure 7 oth
22. graph bands Bar graphs divide the EEG frequency range into bands delta theta alpha etc You can choose five bands or nine Selecting nine gives a more fine grained picture of the spectrum 6 1 2 Site Differences The assessment report looks at left right and front back differences in the EEG These are reported as percentages For example in the sample report in appendix A you see that between F3 and F4 there 1s a difference in theta amplitude of 2 0 The order of the sites 1s important because 1t tells you which site has the larger amplitude The figure is calculated as 1 site minus 2 site e g F3 minus F4 If the first site amplitude is larger the difference 1s positive gt 0 while 1f the second site amplitude 1s larger the difference 1s negative lt 0 The figure 1s calculated as a percentage of the smaller of the two The same convention applies to other reports e g the comparison report section 6 3 6 2 The Site Analysis Report Pressing the button labelled Step 3A will open a summary report based on the data recorded for a single site You ll be prompted to select a site data text file on which to base the report from a dialog window Remember the names were created automatically from the site name plus protocol e g O1 EOECEO Once you ve selected the site data a report options dialog window will open the same one as for the assessment report shown in figure 9 and described in section 6 1 1 Th
23. ion of the main frequency band amplitudes over the course of the recording session An important difference 1s that artefact has not been excluded from this data 2 1 Adjusting Filters The BioEra EEG Data Recording application uses a set of filters to compute frequency band amplitudes coherences and dominant frequencies You have the option to adjust these filters for example you can make small adjustments to the frequency ranges used Click the button Edit Assessment Filters This starts a simple BioEra application offering a set of buttons one for each filter see figure 2 below Clicking one of these buttons opens a further dialog window in which you can adjust the filter settings Figure 3 below shows an example gt BioEra 3 059 EA Filters Edit Amplitude Band Filters Coherence Band Filters Delta Filter Settings Delta Filter Settings Theta 1 Filter Settings ThetaFilter Settings Theta 2 Filter Settings Alpha Filter Settings Alpha 1 Filter Settings Beta Filter Settings Alpha Z Filter Settings Hi Beta Filter Settings Beta 1 Filter Settings Dominant Frequency Filters Beta 2 Filter Settings Overall Filter Settings Beta 3 Filter Settings Alpha Filter Settings Beta 4 Filter Settings Beta Filter Settings Theta Filter Settings Alpha Filter Settings Beta Filter Settings High Beta Filter Settings Figure 2 The BioEra Edit Filters application EEG Assessment User Guide co
24. l is designed to show the effect of the challenge on brain state Baseline This protocol 1s very similar to baseline challenge above except that instead of a Stimulation task you can apply some form of brain stimulation such as a brainwave entrainment technology You can test to see 1f a possible therapeutic intervention has the desired effect on brain state When you select this protocol you ll be prompted to select an audio file which the BioEra EEG assessment application will play 1n a loop during the stimulation phase If you want to test a form of stimulation other than an audio file e g a light and sound machine you can cancel the file selection and then activate the stimulation manually at the appropriate point The York Biofeedback website offers for download some sample audio files containing isochronic beats at various frequencies which may entrain the brain 3 Overview of the Assessment Data As explained in section 2 in the assessment process we record EEG data creating data files for each EEG channel of each recording Later we create reports based on this data and this generates more files html files and image files in png format for the report graphs The Platform application manages this data for you The files are saved in the assessment folder that you created or selected in the beginning The assessment folders are organised as part of a tree structure depicted in figure 5 below Each
25. l store all the files associated with your assessment This folder will be created in your user folder You can also select an existing folder but in most cases 1t would make more sense to create separate assessment folders for data recorded at different times Press either of the buttons Create New Assessment Folder or Select Existing Assessment Folder figure 1 Record EEG data using the BioEra EEG data recording application Typically you d run this step several times with different sites to create a more comprehensive assessment Press the button Record New EEG Data to start this application The EEG data recording application 1s covered in section 4 below Create an assessment report This summarises all the data and highlights key patterns and relationships for all the recorded data Simply press the button View Assessment Report the report will open in your default web browser 1t is created in html format If you want a closer look at the data you can create a single site report or a sites comparison report by pressing the buttons for step 3A and step 3B in the Platform You ll be prompted to select site s from amongst those you recorded from Most users won t need this step because the overall assessment report will be sufficient 6 A further option for analysing data is to use the BioEra assessment review application Pressing the button Review Recording BioEra starts this application It shows the progress
26. me initial set up tasks such as selecting the type of EEG amplifier you re using If you haven t done so yet see the Installation and Set up Guide The assessment process is managed from the York Biofeedback Platform application described in the Installation and Set up Guide For the data gathering phase of the asses the software uses applications built with BioEra a third party software product The software works with several devices For an up to date list of supported hardware please see the York Biofeedback website You have the option to select Simulator as the EEG source This offers a means of learning to use the software without the encumbrance of the hardware set up The software simply replays an EEG recording in a loop as though it were live data You can go through all the steps of assessment but of course the resulting analysis will not be realistic 1 1 Overview of the EEG Assessment Process To recap there are two main stages 1 data collection and 11 analysis and report generation The software offers flexibility e You can record 1 2 or 4 channels of EEG at a time e You choose what sites on the scalp to record from and how many In other words data is gathered in a sequence of recordings and then pooled for analysis e You can record EEG under different conditions such as eyes closed EC eyes open EO or challenge condition CC At the beginning of a recording you ll select an assessment protocol whi
27. n Windows 8 Find the the incorrectly named file e g Fz_EC txt Open it for editing using WordPad At the end of the file you should see a line site Fz Change the site name to the correct one e g Cz Save and close the file Lastly rename it replacing the site in the file name with the correct one e g to Cz EC txt FE 9 FEC data WordPad Home View A Cut Courier New lo A d E E iz E im sj E3 db Fina B Copy ab Replace Paste pz 0 da e W m lar pae Je ate ana set ar Clipboard Font Paragraph Insert Editing 1195110 110r 1 12 1 61314 14 1 15 1016 117 1 18 1 19 1 20 1 21 1 22 1 23 1 24 5 1116943 3 036499 4 7302246 1 7547607 1 6479492 0 7171631 1 7700195 1 1901855 8 795811 10 052356 2 0 1 9378662 2 6245117 4 623413 1 3580322 0 32043457 1 0375977 1 9226074 1 0986328 10 052356 10 052356 2 0 1 8005371 2 5939941 4 5928955 0 579834 0 88500977 0 79345703 1 449585 0 9918213 9 801046 9 801046 2 0 2 1514893 1 9989014 4 2877197 1 8310547 1 1749268 1 083374 1 373291 0 9613037 9 549738 9 549738 2 0 2 3498535 2 5482178 3 692627 1 5716553 0 5493164 1 2207031 1 1291504 0 8392334 9 549738 9 549738 2 0 1 5716553 2 8076172 5 4626465 0 8087158 0 8239746 1 0986328 1 2969971 0 93078613 9 549738 9 549738 2 0 1 7242432 2 7770996 4 3792725 0 8087158 1 1749268 0 7324219 1 0223389 1 0070801 9 549738 9 549738 2 0 1 2817383 2 5634766 4 8675537 0 9460449 1 2664795 1 2817383 1 4953613 1 0681152
28. nd Amplitudes EC 3 5 F3 MA F4 3 vii tities F3 SD tie F4 SD 25 LELE o vi 1 5 lt S MEH H a 1 I WU UM WW A Ls 0 5 0 Theta SMR High Beta Delta Alpha Beta Dominant Frequencies Data Band Fs In mm Overall or 6 2 Hz 6 0 Hz 0 3 Hz DECH Overall F3 F4 Dominant Frequencies EC F3 EN F4 ZS F3 SD Hu F4 SD Beta Alpha 0 5 10 15 20 25 Dominant Frequency Hz Ratios EC Ratio To Ja an Epochs Data F3 Epoch Condition Delta Lo Beta Hi Beta Beta DF 0 58 uV 1 02 uv 18 7 Hz 0 67 uV 0 95 uv 19 0 Hz 0 66 uV 0 96 uv 19 9 Hz Epochs Data F4 Epoch Condition Delta Theta Alpha rond ARE Beta Lo Beta Hi Beta DF SEH Beta DF 1 EC 1 49 uV 2 54 uV 2 86 uV 0 94 uv 0 87 uV 1 08uV 0 57uV 0 93uV 7 4 Hz 10 5 Hz 20 6 Hz 2 EC 1 80 uV 2 51uV 2 65 uV 1 26 uv 0 65 uV 0 97uV 0 60uV 0 93uV 5 8 Hz 9 9 Hz 18 6 Hz 3 BC 1 90 uV 2 36 uV 2 66 uV 1 30 uv 0 84 uV 1 06 UY 0 61uV 0 99uV 4 6 Hz 9 7 Hz 21 4 Hz
29. nd controls are available and these are associated with channel 1 When recording from 2 or 4 sites you should select for channel 1 the site that will most clearly show artefacts Eye blink artefact reflected in the delta filter is clearest at sites closest to the eyes So for example if you re recording from Fz and Oz you should choose Fz as your channel 1 site If you re recording from F3 and F4 then 1t makes no difference 6 Data Analysis and Report Generation The value of assessment 1s in analysing the recorded data at a level where you can discern significant patterns Such patterns offer targets for therapy for example they can directly suggest EEG neurofeedback training protocols To recap the data collection stage of the assessment process produces two files for each site investigated There are the the site data text summary file and the BioEra session file in edf format Reports are based on these files There are three report types 1 assessment report 11 site report and 111 sites comparison report They are covered in sections 6 1 6 2 and 6 3 respectively These three reports are created in html format and are opened in your default web browser e g Internet Explorer or Firefox You need to have such a browser installed but you don t need a live internet connection You can of course use the browser s print function to print a copy of the report Artefact containing data 1s excluded from the calculations for all thre
30. ort ee 20 Appendix B Sample Site Analysis Hencort aaa a kakaa aaa aaa aaa aaa aaa aaa 24 Appendix C Sample Sites Comparison Hepncort aaa aaa aaa kakaa aa aaa aaa 28 EEG Assessment User Guide copyright Glyn Blackett page 1 1 Introduction Neurofeedback 1s a process of exercising some particular aspect of brain functioning with the aim of enhancing performance Often the choice of what specific aspect is guided by an assessment of the individual brain s style of functioning This user guide presents the EEG assessment functions available with York Biofeedback s Mind Body Training Tools software In broad terms there are two stages of the EEG assessment process 1 gathering recording EEG data and 11 analysing the data and presenting it in summary reports The software is designed for flexibility you can create as much or as little assessment data as you consider appropriate You choose the sites to record from using 1 2 or 4 channels at a time You select a protocol which dictates the seguence of recording conditions eyes closed eyes open etc This document teaches you how to operate the software but assumes you already understand what EEG 1s and how it 1s measured quantified and interpreted It does not cover hardware set up including sensor placements or how to select a training protocol based on the assessment The document assumes that you ve successfully installed the software and carried out so
31. pyright Glyn Blackett x settings advanced features Element Filter type Chebyshev mt Band BandPass ej Min frequency Hz NEM Max frequency Hz ha ooo o Filter order EA Chebyshev ripple Ins Filter delay ms 562500 Filter response Implementation FIDLIB ok Cancel Apply Figure 3 Sample filter properties dialog As you can see from figure 2 there are several frequency band filters you can set and also dominant frequency filters and coherence filters Further explanation of all the filter properties is beyond the scope of this document and adjusting them should probably be considered for expert users only 2 2 Recording New Assessment Data When you press the button Record New EEG Data a dialog will open see figure 4 below EEG Assessment 1 Select number of channels 2 Check impedance s Run BioEra Impedance Check App 3 Select Protocol 8 EC only EO FC FO EO EC EO Challenge Baseline Challenge Baseline Stimulation 4 Select assessment site s 6 Record EEG data Cancel Figure 4 Record EEG data dialog EEG Assessment User Guide copyright Glyn Blackett page 6 You need to make a number of selections 1 Recording using one two or four channels This will depend in part on the capabilities of your amplifier 2 Select an assessment protocol which details the sequence of conditions Your choices are described in section 2 2 1 below 3
32. s are not used in the report calculations Section 5 discusses artefact exclusion 2 Running an Assessment This section describes the practical steps needed to run an EEG assessment Later sections explain what s involved in these steps in greater detail The EEG Assessment tab of the Platform application see figure 1 features a set of buttons that reflect the seguence of steps y York Biofeedback Software Mind Body Training Tools Set up Heart Rate Variability HEG Neurofeedback Breathing EMG Muscle Tension GSR 8 Skin Temperature EEG Assessment EEG Training Selected Trainee Assessment Folder Default User Assessment 16 10 2013 Edit Assessment Filters Step 1 Create New Assessment Folder Step 2 Record New EEG Data Step 3 View Assessment Report Step 3A View Site Report Step 3B View Comparison Report OR Select Existing Assessment Folder Documentation EEG Assessment User Guide Step 3C Review Recording BioEra YORK BIOFEEDBACK MIND BODY TRAINING TOOLS www york biofeedback co uk AN Figure 1 Assessment tab of the Platform application In summary the steps are 1 Create a new user or select an existing user This step is done from the Set up tab of the Platform press the User amp Data Options button See the Installation amp Set up Guide for more details Create a new assessment folder which wil
33. show one of the two recordings and it won t say which one in other words it 1s not recommended in general However the data 1s still available so that you can look at it in site analysis and sites comparison reports see section 6 for details of the report types 3 3 The Site Data File in Detail Understanding the summary text file is not necessary for running assessments or generating reports This section is offered for expert users you may skip over it 1f you wish In the summary data file there 1s one line of text per sub epoch Since this file 1s stored as simple text it can be viewed using a number of different applications such as Microsoft s WordPad or a spreadsheet application An example is shown in figure 6 Each line contains a sequence of numbers The first is the sub epoch number and the third is the epoch number The second number marks the epoch as either free of artefact 0 0 or containing artefact 1 0 if the latter the whole line 1s 1gnored during the generation of the site analysis and sites comparison reports To repeat the BioEra data recording application always waits until 1t has enough good data The rest of the numbers are the average EEG amplitudes coherences and dominant frequencies for the sub epoch 3 4 Editing The Site Name If you realise after recording that you made a mistake in selecting the site name you can recover Navigate to the assessment folder using Windows Explorer File Explorer i
34. use in the main chart to select an area of interest If you click and drag over an area of the axis you will zoom in on one dimension only Alternatively right click your mouse over the main chart area to bring up a menu offering numerous zoom options including reverting to the full chart area Note that if you zoom in on a sub section of the horizontal time ax1s the upper chart showing the assessment phases will not update in sync with the main chart You can print the report click on the Report menu top left Appendix A Sample Assessment Report This sample report is based on a simple assessment consisting of two 2 channel recordings creating four data files The first recorded F3 and F4 in EC only the second Fz and Oz with EC EO EC Client s name Smith John Assessment date 21 06 2012 15 38 59 Site Bar Graphs Legend blue lt eyes open EO gold lt eyes closed EC or baseline pink lt challenge condition CC F3 Fz F4 bi x gt 3 S E za e E 2 u 9 a E a E a Kg 0 o cu cu om cm So e vo uo m T TT DH D u 0 0 u ug D wr T cy o SE UV UE UN U H ott e e m m mJ Z 2 x es m m a OBE aag CET eS a X nto oS E Fra 4 ELFO Oz A 3 JE 2 al 34 e a E 1 lt r 0 N A NA D D o n u um 0 0 0 0 m m 56053300000 E m c m oim Er s Theta Beta Ratio Site EC EO Chal Fz 1 75 3 14 0 00 F3 1 73 0 00 0 00 F4 1 72 0 00 0 00 Oz 1 15 1 4
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