WO2000044279A1

WO2000044279A1 - Visualisation system

Info

Publication number: WO2000044279A1
Application number: PCT/GB2000/000204
Authority: WO
Inventors: Gino Francesco
Original assignee: Graf International Limited
Priority date: 1999-01-27
Filing date: 2000-01-27
Publication date: 2000-08-03
Also published as: AU2303500A

Abstract

The present invention relates to a system for the visualisation of waveforms especially waveforms derived from an activity of a human or other living body. In its broadest sense, the present invention takes a waveform, however that may have been generated, and processes the waveform into a pleasing graphic form which may be printed or otherwise displayed. In particular, there is described a visualisation system comprising acquisition means for acquiring an electrical signal corresponding to a function of a subject human or other body; data processing means and graphic processing means, the data processing means processing the electrical signal into a form from which the graphic processing means can produce a graphic representation of the function of the subject. There is also described a method of generating a graphic representation of a function of a human or other body, the method comprising the steps of obtaining an electrical signal corresponding to the function; processing the signal to obtain a dataset; and processing the dataset to produce a graphic image. Preferably the function relates to a physiological process, typically a brainwave function acquired using an electroencephalograph.

Description

VISUALISATION SYSTEM

The present invention relates to a system for the visualisation of waveforms especially

waveforms derived from an activity of the human or animal body.

In its broadest sense, the present invention takes a waveform, however that may have been generated, and processes the waveform into a pleasing graphic form which may be

printed or otherwise displayed.

According to the present invention there is provided, in one aspect, a visualisation system

comprising acquisition means for acquiring an electrical signal corresponding to a

function of a subject human or other body; data processing means and graphic processing

means, the data processing means processing the electrical signal into a form from which

the graphic processing means can produce a graphic representation of the function of the

subject.

In another aspect, the present invention provides a method of generating a graphic

representation of a function of a human or other body, the method comprising the steps

of obtaining an electrical signal corresponding to the function; processing the signal to

obtain a dataset; and processing the dataset to produce a graphic image.

Preferably the function relates to a physiological process. Typically it is a brainwave

function and the acquisition means comprises an electroencephalograph. Alternatively, the function may be an audible output from the body, such as speech or singing. Typically, in this case, the acquisition means comprises a microphone coupled to

a computer or other means for digitising the sound output.

Preferably, the data processing means and/or the graphic processing means includes data

selection and manipulation means adapted to enable a user to select and manipulate

portions of the data from which the graphic representation is produced. Preferably, the

system also includes means for combining datasets corresponding to a plurality of

electrical signals.

The above and other aspects of the present invention will now be described in further

detail with reference, by way of example only, to the accompanying drawings in which:

Figure 1 is an electroencephalogram of a subject;

Figure 2 shows the data encompassed in the T3 channel of the

encephalogram of Figure 1, extracted into a spreadsheet format;

Figure 3 is a power spectrum of the data of Figure 2;

Figure 4 is an enlarged section of the spectrum of Figure 3;

Figure 5 is an expanded version of the spectrum of Figure 3;

Figure 6 shows the spectrum of Figure 4 displayed in the format of a radar

scan;

Figure 7 is a collection of superimposed radar contour charts derived in the

same manner as Figures 2 to 6 from the data of Figure 1 ;

Figure 8 is a filled radar chart version of the chart of Figure 7;

Figure 9 is a spectrum of a sampled section of a voice sound name; Figure 10 shows a radar contour chart derived from the spectrum of Figure

9; Figure 1 1 shows a filled radar chart derived from the spectrum of Figure 9;

and

Figure 12 shows a bubble chart version of the charts of Figures 7 and 8.

In a first embodiment, the system of the present invention obtains data corresponding to

brain electrical activity by means of an electroencephalograph (EEG) apparatus which

includes a plurality of electrodes placed upon the subject's head. EEG is typically used to monitor beta, alpha, theta and delta brainwave channels. The raw electroencephalogram

data obtained is illustrated in Figure 1 and comprises a plurality of electrical signals or

waveforms 10 corresponding to channels of data relating to the different types of

brainwave (α, β, θ, γ) and also to data retrieved from different locations on the skull, for

example, forehead, temples and so on. In the following illustrative example, a single

channel, known as T3, is used to generate the data to be processed, but any one or more

channels could be used at the option of the user. A channel waveform with a wide

variance in peak height could be chosen as being expected to produce an interesting

graphic form. The waveform of a channel which is associated with a particular brain

function might be selected.

The waveform data is converted into a spreadsheet format as shown in Figure 2. This

conversion can be affected by suitable software such as the commercially available

LabNiew (TM) and MATLAB (TM) software which can be used to respectively extract

and analyse the EEG data. The spreadsheet data can then be processed using other software to generate preliminary waveforms such as that shown in Figure 3. Microsoft Excel® 97 includes suitable routines. In Figure 3, the data from twenty three separate scans of the T3 channel have been processed as waveforms and superposed. It will be

observed that there is a sharp peak at the 50Hz position. This, in fact, arises through

interference from the mains electricity supply and can be filtered out. As shown in Figure

4, all or only a section of the full scan can be selected for further processing. Indeed, for

the present purposes the range from 8Hz to 20Hz is preferred. In Figure 5, the scale of

the abscissa of the spectra of Figure 3 has been expanded and then, using a routine in

Microsoft Excel, converted into a "radar" chart (Figure 6). Preferably, for visual effect,

each of the twenty three scans would be represented in Figures 3 to 6 in a different

colour.

Figure 7 illustrates the same data processed into a radar chart using slightly different

parameters. Figure 8 shows the same chart but with shading added to each set of scan

data. It is important to realise that as each scan is superposed it may overlie the

colouration of the spectrum below such that, in the shaded graphic, fewer than the full

twenty three spectra may be visible.

In the application of the present invention, the data used may be extracted from an EEG

used for medical purposes. However, this is not essential for the purposes for which the

present invention is particularly intended. As such, accuracy in data acquisition is not of

paramount importance. The present inventor has also devised a headset (not illustrated)

which includes means for holding the headset on a wearer's head and incorporates the

necessary electrodes to enable a brainwave activity scan to be obtained. Typically, the electrodes need only sense a single channel. The headset is connected to an electroencephalogram processing unit, typically in the form of a computer expansion

card. The data is then software processed further as described above to produce the

output graphic. Additional channels can be "generated" electronically based on the data derived from the channel data actually acquired.

The quantity of data required to be acquired will depend upon the level of detail required

in the final image. Acquisition for ten seconds may provide sufficient data for a single

channel.

To illustrate the wide application of the present invention, reference is made to Figures 9,

10 and 1 1. Instead of an EEG, the waveform is the power spectrum derived from

sampling (at 22.05 KHz) a 3 to 5 second recording of a person's speech (Figure 9). The

recording was made using a conventional computer fitted with a sound card and

microphone and was saved as a 'Wave sound (.wav)' file. As before the data is processed

into a Microsoft Excel® spreadsheet from which a radar contour plot (Figure 10) and

radar filled plot (Figure 11) were obtained. Figure 10 and 1 1 show plots obtained at just

one sampled frequency. Several frequencies can be sampled sequentially and the results

overlayed to produce a multiple layer graphic as, for example, is shown in Figure 7 or 8.

Alternative graphic outputs are, of course, derivable from the same data. For example,

the same data used to produce the radar plot of Figure 8 can produce a scatter chart of

the "bubble" type as shown in Figure 12. The graphic image (as, for example, shown in Figures 6 to 8 or 10 to 12) can be combined with other images before being output. For example, the image could be a photographic image of the person who provided the original data or simply an additional

background graphic.

The graphic image can then be output in the form desired by the user. For example, it

could be printed out simply to provide a picture for mounting or for forming greetings

cards or badges etc. Alternatively, the graphic can be reverse printed using transfer inks

to enable the graphic to be subsequently applied to clothing such as T-shirts.

The image can, of course, be saved in a digital format for further manipulation and

subsequent use by the user. Particularly as regards the multiple layer or three-

dimensional graphics, these can be further processed into holographic images.

Additionally, a plurality of images, perhaps collected over an extended period of time,

can be adapted into the form of a personalised cartoon or screen saver for a computer.

The data could be adapted such as by rotation, translation and/or changing of colours,

such that a moving and changing graph can be displayed on a computer screen,

Additional features, such as zooming in and zooming out could be added. All of these

forms of data manipulation are well known for computer animation and screen savers and

would be readily apparent to a person skilled in the art. It will be apparent that any

portion of the data (for example, the frequency portion) from any EEG scan or sound

extract could be used to produce a screen saver or other program, as can any of the EEG

channels. It is also envisaged that the program could be formed from scans of a plurality

of individuals, such as of all the people who would use a particular computer. The data may be combined in such a way as to provide an animated interaction between each data

set.

For the finished screen saver or other program, the user will be able to see on the screen of their personal computer their personal brainwave which will be automatically

manipulated to cause visually appealing effects. This data has never been used for such a

purpose before and the user will have a sense not only of this unique data which they may

not have appreciated before but will also provide an important psychological link with the

computer itself.

The skilled reader will readily appreciate methods for improving the capture of data on

the EEG, such as coupling the electrodes to the right parts of a person's head, providing

or, selectively, withdrawing particular stimuli from the person during capture of

brainwaves (for example ensuring the person closes his/her eyes during data capture, and

so on).

It is not necessary for the brainwave or audible data to be human data, it could, for

example, relate to a bird or animal of particular interest to the user, for example a pet.

Given the above discussion of the various aspects of the present invention, those skilled

in the art will be readily able to devise and construct apparatus suitable for acquiring and

processing the relevant data without further instruction.

Claims

1. A visualisation system for visualising a function of the body of a living being; the system comprising acquisition means for acquiring an electrical signal corresponding to a

function of a subject body; data processing means and graphic processing means, the data

processing means processing the electrical signal into a form from which the graphic

processing means can produce a graphic representation of the function of the subject.

2. A visualisation system as claimed in Claim 1 wherein the function relates to a

physiological process.

3. A visualisation system as claimed in Claim 2 wherein the physiological process is

a brainwave function and the acquisition means comprises an electroencephalograph.

4. A visualisation system as claimed in Claim 1 wherein the function is an audible

output from the body.

5. A visualisation system as claimed in Claim 4 wherein the acquisition means

comprises a microphone coupled to a computer or other means for digitising the sound

output.

6. A visualisation system as claimed in any one of claims 1 to 5 wherein the data

processing means and/or the graphic processing means includes data selection and

manipulation means adapted to enable a user to select and manipulate portions of the data

from which the graphic representation is produced.

7. A visualisation system as claimed in Claim 6 wherein the system also includes means for combining datasets corresponding to a plurality of electrical signals.

8. A method of generating a graphic representation of a function of a body of a

living being, the method comprising the steps of obtaining an electrical signal

corresponding to the function; processing the signal to obtain a dataset; and processing

the dataset to produce a graphic image.

9. A method as claimed in Claim 8 wherein the function relates to a physiological

process.

10. A method as claimed in Claim 9 wherein the physiological process is a brainwave

function and is obtained by means of an electroencephalograph.

11. A method as claimed in Claim 8 wherein the function is an audible output from

the body.

12. A method as claimed in any one of claims 8 to 11 wherein portions of the data may be selected and manipulated prior to production of the graphic representation.

13. A method as claimed in Claim 12 wherein datasets corresponding to a plurality of electrical signals are combined.