Clinician's Guide - Bio-Medical Instruments, Inc.

which initially lies on the right hand side of the EEG linegraph. You can move it to the
left and look at the spectrum magnitudes for any one second portion of the EEG.
In addition, the average (to the number of seconds the display has been running) microvolt
values for selected band widths and ratios is displayed, to the right of the 52-58 Hz
linegraph, on the right hand side of the screen.
Event Markers
You can right-click and set an event marker as a dotted line. This enables you to write a
note describing the event.
• To see information for markers. Set the time frame to size to session. Then
left click over any marker and the event description will pop-up. Then use
alt-key and draw a small box at that point and you will see the event.
However, it will not come up with a time scale. To get out of it you click on
the circular arrow next to the calculator box in the upper right hand side of
the screen.
• We use event marking without writing a note to mark eye blinks and client
movement when we are doing an assessment. This makes sure that you catch
and eliminate all the artefacts before doing statistics.
Removing Artefacts from the EEG:
While reviewing the data the trainer can hold down Ctrl and left click while dragging the
mouse across the data to mark a section that contains artifact. It turns grey when you
release the mouse. When you click the calculator icon at the top of the screen the grey
areas that mark artefacts will be excluded from the statistical calculations. (Important:
Always click that calculator icon before you click print. If you forget to do this the
statistics that you print will still include all the segments you thought you artifacted out.)
The grey area is the area that you wish the program to ignore (no data is deleted) when
statistics are calculated. The delete option for these grey highlighted areas only
refers to ‘removing’ the artifact segment grey box.
• Thus, the Infiniti program can ignore these sections that you have
highlighted when you request statistics. If you right-click over the ones
you don’t want to mark any more and choose delete rejection segment
then the program just removes the grey highlighted box (i.e., There is no
loss of data).
Recording
We usually have the client blink before recording and sit comfortably and still while we
are recording. Most of the record, under these circumstances, may be artifact free.
Nevertheless, as noted above, we always watch the client during the recording and click
the space bar whenever there is movement or an eye-blink. This places a marker on the
screen which helps you accurately identify artefacts. For details on Artefacting see The
Neurofeedback Book (it can be obtained through www.AAPB.org).
The 52-58 Hz EMG noise line below the EEG helps you distinguish muscle artefact from
high beta neuronal activity. (52 Hz is above the desirable 39 - 41 Hz “Sheer rhythm”
activity and will also avoid 50 Hz or 60 Hz electrical noise.
Copyright ADD Centres Ltd. Prepublication – 1 st draft. Please do not copy. Dr. Thompson 905-803-8066 Canada 50