Imaging facial signs of neuro-physiological responses

• US 8,401,261 B2
• Filed: 09/25/2008
• Issued: 03/19/2013
• Est. Priority Date: 09/25/2007
• Status: Active Grant

• Current Assignee: University of Houston System
• Original Assignee: University of Houston System
• Inventors: Pavlidis, Ioannis
• Primary Examiner(s): Cao, Phat X
• Assistant Examiner(s): Vieira, Diana C
• Application Number:
  US12/237,889
• Publication Number:
  US 20090080730A1
• Time in Patent Office: 1,636 Days
• Field of Search: 382/115, 382/117, 382/118, 382128-134
• US Class Current: 382/128
• CPC Class Codes: A61B 5/015 By temperature mapping of body part
• CPC Class Codes: A61B 5/026 Measuring blood flow A61B3/1233, A61B3/1241 take precedence
• CPC Class Codes: A61B 5/1135 by monitoring thoracic expansion
• CPC Class Codes: A61B 5/4035 Evaluating the autonomic nervous system
• CPC Class Codes: A61B 5/726 using Wavelet transforms
• CPC Class Codes: G06V 2201/03 Recognition of patterns in medical or anatomical images
• CPC Class Codes: G06V 40/168 Feature extraction; Face representation

Abstract

The invention provides an integrated framework for detecting peripheral sympathetic responses through imaging. The measurements may be performed on three facial areas of sympathetic importance, that is, periorbital, supraorbital, and maxillary. Because the imaging measurements are thermal in nature and comprise multiple components of variable frequency (i.e., blood flow, sweat gland activation, and breathing), wavelets are used as the image analysis framework. The image analysis may be grounded on GSR signals.

Claims

1. A system for quantifying at least one sympathetic response on the face, the system comprising:

a thermal imager adapted to measure signals from at least one facial region selected from the group consisting of supraorbital, periorbital, and maxillary regions;

wherein the measured signal is at least one selected from the group consisting of blood flow in the facial/ophthalmic arteriovenous complex, blood flow in the supraorbital area, perspiration in the supraorbital area, and perspiration in the maxillary area; and

at least one ground-truth probe synchronized with the thermal imager via an electronic circuit.

2. The system of claim 1 wherein the at least one ground-truth probe is selected from GSR sensors, thermistor sensors, piezo-respiratory belt transducers, and combinations thereof.

3. The system of claim 1 further comprising a computer in communication with the thermal imager.

4. The system of claim 3 wherein the computer is adapted to perform wavelet energy analysis on the measured signal.

5. A method for quantifying at least one sympathetic response on the face, the method comprising measuring signals from at least one facial region selected from the group consisting of supraorbital, periorbital, and maxillary regions:

wherein said sympathetic responses are quantified through measurement or at least one selected from the group consisting of blood flow in the facial/ophthalmic arteriovenous complex, blood flow in the supraorbital area, perspiration in the supraorbital area, and perspiration in the maxillary area; and

obtaining of at least one corroborating probe signal selected from perspiratory signals extracted through GSR, thermal signals extracted through thermistor sensors, and breathing signals extracted through a piezo-respiratory belt transducer.

6. The method of claim 5 comprising obtaining at least one measurement via thermal imaging.

7. The method of claim 5 wherein at least one of the corroborating probe signals is synchronized with the measurement via thermal imaging.

8. The method of claim 5 wherein the at least one sympathetic response is quantified through wavelets analysis.

9. The method of claim 8 comprising a multi-resolution wavelets approach.

10. A method of extracting a breathing component from thermal imaging signal data obtained from the maxillary area of the face, the method comprising:

performing multi-resolution wavelets analysis to determine phasic and tonic components; and

examining the lower scale (higher frequency) wavelet energy for extraneous modulation indicative of a breathing component.