Data collection for vestibulogram construction

Patent metadata

Field	Value
Publication number	US-9795335-B2
Application number	US-201314390923-A
Country	US
Kind code	B2
Filing date	Mar 15, 2013
Priority date	Apr 6, 2012
Publication date	Oct 24, 2017
Grant date	Oct 24, 2017

Abstract

The methods, systems, and computer program products described herein enable the amount of information that can be acquired during a defined period of vestibular testing to be significantly increased while also significantly reducing the time required to collect data during such vestibular testing. These objects are achieved by intelligent data collection methods and systems configured to adaptively control a motion platform in a way that increases the amount of information gleaned from each data collection event and to achieve synergies based on the different types of, and the order of, data analysis and calibration methods used.

First claim

The invention claimed is:

1. A method for assessing a subject's vestibular system, the method comprising:
administering a psychometric test to a subject and measuring responses of the subject to obtain a set of values, wherein administering the psychometric test comprises:
positioning the subject on a motion platform that includes a device for supporting the subject and is configured to execute motion profiles,
obtaining a first estimate of a parameter vector of the subject's psychometric function based on the subject's perception of motion in response to a first motion profile set wherein the subject's perception of motion is received using one or more input devices, and
adaptively selecting, using one or more processing devices, a subsequent motion profile based at least in part on the first estimate, determining at least one fit parameter that represents a distribution of the set of values and represents a characteristic of the subject's responses to the psychometric test;
estimating a bias quantity associated with each said fit parameter; subtracting the bias quantity from each said fit parameter to obtain a bias-reduced estimate of the fit parameter;
scaling the bias-reduced estimate of the fit parameter by a scale-factor to obtain a final estimate of the fit parameter; and
generating a quantitative measure representing the subject's vestibular system based on the final estimate of the fit parameter.

2. The method of claim 1 , wherein the scale factor has a value substantially equal to or less than one.

3. The method of claim 1 , wherein the responses of the subject are measured for stimuli corresponding to a plurality of values of a test parameter associated with the motion profiles and the responses to different values of the test parameter are scaled using a corresponding scaling function to obtain the set of values.

4. The method of claim 1 , wherein the responses of the subject are obtained by providing a stimulus to the subject for a predetermined number of times to measure the responses of the subject, wherein a level of the stimulus is associated with a corresponding motion profile.

5. The method of claim 1 , wherein the distribution is represented as a cumulative distribution function.

6. The method of claim 1 , wherein the at least one fit parameter is determined using a numerical maximum-likelihood method.

7. The method of claim 1 , wherein the bias quantity represents a first order asymptotic bias.

8. The method of claim 1 , further comprising selecting the subsequent motion profile to reduce uncertainty in the estimate.

9. The method of claim 1 , further comprising selecting the subsequent motion profile based at least in part on Fisher information associated with the estimate.

10. The method of claim 1 , further comprising correcting for lapses in the subject's attention by identifying outlier data and eliminating the outlier data prior to obtaining the first estimate.

11. The method of claim 1 , wherein the bias reduced estimate of the fit parameter is obtained iteratively, the method further comprising:
estimating a second bias quantity for a first bias-reduced estimate; and
subtracting the second bias quantity from the first bias-reduced estimate to obtain the bias-reduced estimate.

12. A system for assessing a subject's vestibular system, the system comprising:
a test apparatus for providing a motion profile to a subject and measuring responses of the subject to obtain a set of values as part of a psychometric test the test apparatus comprising:
a motion platform that includes a device for supporting a subject, wherein the motion platform is configured to execute motion profiles;
one or more input devices configured to receive the subject's perception of motion;
a memory; and
one or more processors programmed to obtain a first estimate of a parameter vector of a psychometric function of the subject based on the subject's perception of motion in response to a first motion profile set, and to adaptively select a subsequent motion profile based at least in part on the first estimate;
wherein the one or more processors are further configured to:
determine at least one fit parameter that represents a distribution of the set of values and represents a characteristic of the subject's responses to the psychometric test;
estimate a bias quantity associated with each said fit parameter;
subtract the bias quantity from each said fit parameter to obtain a bias-reduced estimate of the fit parameter;
scale the bias-reduced estimate of the at least one fit parameter by a scale-factor to obtain a final estimate of the fit parameter; and
generate a quantitative measure representing the subject's vestibular system based on the final estimate of the fit parameter.

13. The system of claim 12 , wherein the scale factor has a value substantially equal to or less than one.

14. The system of claim 12 , further comprising one or more input devices configured to accept the responses of the subject for stimuli corresponding to a plurality of values of a test parameter associated with the motion profiles, and wherein the responses to different values of the test parameter are scaled using a corresponding scaling function to obtain the set of values.

15. The system of claim 12 , further comprising one or more input devices configured to accept the responses of the subject, wherein the responses of the subject are obtained after providing a stimulus to the subject for a predetermined number of times, and wherein a level of the stimulus is associated with a corresponding motion profile.

16. The system of claim 12 , wherein the distribution is represented as a cumulative distribution function.

17. The system of claim 12 , wherein the at least one fit parameter is determined using a numerical maximum-likelihood method.

18. The system of claim 12 , wherein the bias quantity represents a first order asymptotic bias.

19. The system of claim 12 , wherein the processor is configured to select the subsequent motion profile to reduce uncertainty in the estimate.

20. The system of claim 12 , wherein the processor is configured to select the subsequent motion profile based at least in part on Fisher information associated with the estimate.

21. The system of claim 12 , wherein the one or more processors are further configured to correct for lapses in the subject's attention by identifying outlier data and eliminating the outlier data prior to obtaining the first estimate.

22. The system of claim 12 , wherein the one or more processors are configured to obtain the bias-reduced estimate iteratively by:
estimating a second bias quantity for a first bias-reduced estimate; and
subtracting the second bias quantity from the first bias-reduced estimate to obtain the bias-reduced estimate.

23. A non-transitory computer readable storage device having encoded thereon computer readable instructions for assessing a subject's vestibular system, which when executed by a processor, cause one or more processors to perform operations comprising:
obtaining a first estimate of a parameter vector of a subject's psychometric function based on the subject's perception of motion in response to a first motion profile set, wherein a psychometric test is administered to the subject by positioning the subject on a motion platform configured to execute motion profiles;
adaptively selecting a subsequent motion profile based at least in part on the first estimate;
obtaining respon

Assignees

• Massachusetts Eye & Ear Infirmary

Inventors

• Merfeld Daniel Michael
• Chaudhuri Shomesh Ernesto
• Lim Koeun
• Priesol Adrian
• Lewis Richard
• Karmali Faisal

Classifications

• G09B5/00

  Electrically-operated educational appliances (working with questions and answers G09B7/00; simulators G09B9/00; advertising or displaying in general G09F) · CPC title

• A61B5/7221

  Determining signal validity, reliability or quality (preventing, reducing or removing noise induced by motion artefacts A61B5/7207; noise originating from a therapeutic or surgical apparatus A61B5/7217) · CPC title

• A61B5/18 Primary

  for vehicle drivers {or machine operators} · CPC title

• A61B5/0057

  by applying motion other than vibrations, e.g. rolling, rubbing, applying a torque, tribometry · CPC title

• A61B5/16 Primary

  Devices for psychotechnics (using teaching or educational appliances G09B1/00 - G09B7/00); Testing reaction times {; Devices for evaluating the psychological state} · CPC title