EEG control of devices using sensory evoked potentials

• US 8,155,736 B2
• Filed: 03/16/2009
• Issued: 04/10/2012
• Est. Priority Date: 03/16/2009
• Status: Expired due to Fees

• Current Assignee: Neurosky Incorporated
• Original Assignee: Neurosky Incorporated
• Inventors: Sullivan, Tom, Delorme, Arnaud, Luo, An
• Primary Examiner(s): Marmor, II, Charles A
• Assistant Examiner(s): Reddy, Sunita
• Application Number:
  US12/381,887
• Publication Number:
  US 20100234752A1
• Time in Patent Office: 1,121 Days
• Field of Search: 600/544, 600/545, 600/372
• US Class Current: 600/544
• CPC Class Codes: A61B 5/165 Evaluating the state of mind, e.g. depression, anxiety
• CPC Class Codes: A61B 5/18 for vehicle drivers or machine operators
• CPC Class Codes: A61B 5/378 Visual stimuli
• CPC Class Codes: G06F 3/015 Input arrangements based on nervous system activity detection, e.g. brain waves [EEG] detection, electromyograms [EMG] detection, electrodermal response detection

Abstract

An EEG control of devices using Sensory Evoked Potentials (SEPs) (e.g., visually-evoked potentials), is disclosed. In some embodiments, a system receives a plurality of EEG signal samples; generates a stimulus locked average signal using the plurality of EEG signal samples; and determines whether the plurality of EEG signal samples are evoked in response to a pattern of stimulus.

Claims

1. A system, comprising:

a processor configured to;

generate a stimulus-locked average signal of a plurality of EEG signal samples; and

determine whether the plurality of EEG signal samples are evoked in response to a pattern of stimulus events, wherein the determination of whether the plurality of EEG signal samples are evoked in response to a pattern of stimulus events is performed by multiplying the stimulus-locked average by a previously created prototype average; and

a memory coupled to the processor and configured to provide the processor with instructions.

2. The system recited in claim 1, wherein the pattern of stimulus events includes a plurality of light sources emitting light flashes periodically at a fixed frequency.

3. The system recited in claim 1, wherein the pattern of stimulus events includes a plurality of light sources emitting light flashes periodically, including a first light source emitting light flashes a first fixed frequency and a second light source emitting light flashes at a second fixed frequency.

4. The system recited in claim 1, wherein the pattern of stimulus events includes a light source emitting light flashes periodically at a plurality of frequencies, including a first light flash at a first frequency and a second light flash at a second frequency.

5. The system recited in claim 1, wherein the pattern of stimulus events includes a plurality of light sources emitting light flashes at non-periodic frequencies.

6. The system recited in claim 1, wherein the pattern of stimulus events includes one or more of the following:

a pattern of visual stimulus events, a pattern of audio stimulus events, and a pattern of tactile stimulus events.

7. The system recited in claim 1, wherein the pattern of stimulus events includes a plurality of light sources that each provides independent flashing light events.

8. The system recited in claim 1, wherein the plurality of EEG signal samples are evoked as an involuntary response of a user of the system.

9. The system recited in claim 1, wherein the plurality of EEG signal signals include voluntary EEG signal responses.

10. The system recited in claim 1, wherein each of the plurality of EEG signal samples includes a plurality of sample points.

11. The system recited in claim 1, wherein each of the plurality of EEG signal samples is a time series of EEG signal samples.

12. The system recited in claim 1, wherein the stimulus-locked average signal includes a flash-locked average signal.

13. The system recited in claim 1, wherein the determination of whether the plurality of EEG signal samples are evoked in response to a pattern of stimulus events is performed by comparing the stimulus-locked average to a threshold.

14. The system recited in claim 1, wherein the determination of whether the plurality of EEG signal samples are evoked in response to a pattern of stimulus events is performed by multiplying the stimulus-locked average by the prototype average that adapts to the user'"'"'s EEG signals.

15. The system recited in claim 1, wherein the determination of whether the plurality of EEG signal samples are evoked in response to a pattern of stimulus events is performed by integrating the EEG signal data to generate a result, and comparing the result to a threshold.

16. The system recited in claim 1, wherein the determination of whether the plurality of EEG signal samples are evoked in response to a pattern of stimulus events is performed using a time domain classifier.

17. The system recited in claim 1, wherein the determination of whether the plurality of EEG signal samples are evoked in response to a pattern of stimulus events is performed in real-time.

18. The system recited in claim 1, wherein the processor is further configured to:

determine whether a user of the system is looking at a first light source.

19. The system recited in claim 1, wherein the processor is further configured to:

calculate a first peak value of the stimulus-locked average signal, wherein the first peak value is determined based on maximum value minus a minimum value of the stimulus-locked average signal; and

compare the first peak value with a threshold.

20. The system recited in claim 1, wherein the processor is further configured to:

correlate the plurality of EEG signal samples with the pattern of stimulus events using a time offset based on stimulus timing.

21. The system recited in claim 1, wherein the processor is further configured to:

train based on a first user to determine a first signature signal to assist in correlating the plurality of EEG signal samples with the pattern of stimulus events for the first user.

22. The system recited in claim 1, further comprising:

a plurality of electrodes including an active EEG electrode and a reference EEG electrode, wherein the plurality of electrodes detect the plurality of EEG signal samples.

23. The system recited in claim 1, wherein the processor is further configured to:

provide a control signal based on a determination of whether the plurality of EEG signal samples are evoked in response to the pattern of stimulus events.

24. The system recited in claim 1, wherein the processor is further configured to:

provide a control signal to a device based on a determination of whether the plurality of EEG signal samples are evoked in response to the pattern of stimulus events, wherein the device includes one or more of the following;

an entertainment system, an educational system, a medical system, an automobile system, and a computer executing an application.

25. A method, comprising:

measuring a plurality of EEG signal samples using a bio-signal sensor;

generating a stimulus-locked average signal using the plurality of EEG signal samples using a processor; and

determining whether the plurality of EEG signal samples are evoked in response to a stimulus using the processor, wherein the determination of whether the plurality of EEG signal samples are evoked in response to a pattern of stimulus events is performed by multiplying the stimulus-locked average by a previously created prototype average.

26. The method recited in claim 25, wherein the determination of whether the plurality of EEG signal samples are evoked in response to a pattern of stimulus events is performed by multiplying the stimulus-locked average by the prototype average that adapts to the user'"'"'s EEG signals.

27. A computer program product, the computer program product being embodied in a non-transitory computer readable storage medium and comprising computer instructions for:

record a plurality of EEG signal samples;

generate a stimulus-locked average signal using the plurality of EEG signal samples; and

determine whether the plurality of EEG signal samples are evoked in response to a stimulus, wherein the determination of whether the plurality of EEG signal samples are evoked in response to a pattern of stimulus events is performed by multiplying the stimulus-locked average by a previously created prototype average.

28. The computer program product recited in claim 27, wherein the determination of whether the plurality of EEG signal samples are evoked in response to a pattern of stimulus events is performed by multiplying the stimulus-locked average by the prototype average that adapts to the user'"'"'s EEG signals.