This is a preliminary release, still experimental and liable to change.
New facilities in this version.
'Field' displays the electric potential field over the head at a given instant. Place the cursor over a feature of interest and select 'Field' from the cursor choice control.
'Spectrum' allows you to obtain an estimated display of the frequency spectrum of a segment of any channel of the displayed page. Point to the start of the desired segment and drag to the right (minimum 4 seconds). A box will appear and on releasing the mouse button the estimated spectrum will appear.
Unless you are familiar with the system please click here - How to use the viewer - for detailed instructions.
Note: The 'How to use the viewer' system opens in a separate window.
Otherwise click on
I hope that these records will constitute a useful resource
particularly for students of EEG. This is why I have tried to make
the experience as close to that of reporting a routine EEG as
possible.
Limitations of Web browsers mean that the resolution (particularly
the sampling rate) and the speed of the display, cannot approach
that of commercial EEG apparatus.
Nevertheless I think it is valuable to be able to scan the whole
record (not merely the 'interesting bits') and to be able to
examine pages in different montages, to alter the timescale (paper
speed) and gain (amplification) as well as applying high and low
frequency filters.
When you have selected a record for the first time there is a pause of up to 30 - 60 seconds while the display system loads, longer if you are using a dialup connection.
You can then :-
and so on . . .
Horace Townsend