Method and apparatus for measuring the relaxation state of a person

• US 4,665,926 A
• Filed: 11/18/1985
• Issued: 05/19/1987
• Est. Priority Date: 11/17/1984
• Status: Expired due to Term

• Current Assignee: Hanscarl Leuner, Hartwig Klaumunzer
• Original Assignee: Hanscarl Leuner, Hartwig Klaumunzer
• Inventors: Leuner, Hanscarl, Klaumunzer, Hartwig
• Primary Examiner(s): Coven, Edward M.
• Application Number:
  US06/799,158
• Time in Patent Office: 547 Days
• Field of Search: 128/1 C, 128/716, 128/718, 128/719, 128/721, 128/722, 128/723, 128/724, 128/905, 128/671, 128/204.21, 128/205.3
• US Class Current: 600/529
• CPC Class Codes: A61B 5/0816 Measuring devices for examining respiratory frequency measuring frequency of electric signals G01R23/00
• CPC Class Codes: A61B 5/16 Devices for psychotechnics using teaching or educational appliances G09B1/00 - G09B7/00; Testing reaction times ; Devices for evaluating the psychological state
• CPC Class Codes: A61M 2021/0027 by the hearing sense
• CPC Class Codes: A61M 2021/0044 by the sight sense
• CPC Class Codes: A61M 2230/40 Respiratory characteristics

Abstract

In a system for respiratory feedback therapy, relaxation state can be qualitatively measured by forming a quotient between values related to the inhalation/exhalation duration and values related to the pause between inhalation/exhalation phases over intervals of 0.5 to 3 minutes or 5 to 20 respiration cycles.

Claims

1. A method of measuring a degree of relaxation of a subject which comprises the steps of:

measuring respiration movements of said subject and generating a respiration signal representing an inhalation/exhalation phase and an interval between inhalation/exhalation phases for each respiration cycle;

averaging time durations related to a duration t_A of inhalation/exhalation phase and a duration t_P of said interval for a number of respiration cycles of duration T where T=t_A +t_P ; and

forming an average quotient of durations t_P and t_A and displaying a value related to said quotient as a qualitative measurement of the degree of relaxation of said subject.

2. The method defined in claim 1 wherein values corresponding to the duration t_A and t_P are averaged for respiration cycles over equal time durations between 0.5 minute to 3 minutes to provide said qualitative measurement.

3. The method defined in claim 1 wherein a baseline level is established for said respiration signal, such that intersections of successive rising and falling flanks of said signal during the inhalation/exhalation phase with the baseline are separated by a time interval t₁ and intersections of successive falling and rising flanks with said baseline level are separated by a time interval t₂, the relative durations t₂ and t₁ being ascertained to form said qualitative measurement.

4. The method defined in claim 3 wherein the durations t₁ and t₂ are ascertained for at least 5 and at most 20 respiration cycles to obtain said qualitative measurement.

5. The method defined in claim 3 wherein the durations t₁ and t₂ are ascertained for a number of respiration cycles over fixed durations between 0.5 and 3 minutes for said qualitative measurement.

6. The method defined in claim 3 wherein said durations are formed into a direct voltage output signal in accordance with the formula ##EQU3## where C is a constant, and a signal corresponding to the value of said formula is displayed as at said qualitative measurement.

7. The method defined in claim 1 wherein said qualitative measurement is displayed in an analog display.

8. The method defined in claim 1 wherein said qualitative measurement is displayed in a digital display.

9. The method defined in claim 1 wherein values of t_A and t_P are measured over fixed numbers of respiration cycles of duration T between 5 and 20 in number, to obtain each such qualitative measurement.

10. An apparatus for measuring the relaxation state of a subject which comprises:

means for detecting respiration movements of said subject and generating a respiration signal having an inhalation/exhalation phase of duration t_A, separated at least during relaxation of the subject by an interval of duration t_P from a subsequent respiration cycle having a duration T=t_A +t_P ;

signal processing means connected to said detecting means for evaluating a ratio between a value related to the duration t_A to a value related to the duration t_P over a period of at least a number of respiration cycles to form an output representing a qualitative measurement of relaxation state; and

display means for displaying a value corresponding to said output.

11. The apparatus defined in claim 10 wherein said signal processing means comprises means for distinguishing between different signals corresponding respectively to t_A and t_P, averaging said different signals, and forming a ratio of the averaged difference signals over a fixed time period of at least 0.5 minute and at most 3 minutes.

12. The apparatus defined in claim 10 wherein said signal processing means includes a R-C network connected to an amplifier, a comparator connected to said amplifier and generating equal magnitude voltages of positive and negative polarity in dependence upon the polarity of the output of said amplifier, and a further RC-network forming an output element connected to said display means.

13. The apparatus defined in claim 10 wherein said signal processing means includes means responsive to said respiration signal for generating distinct signals related to the durations t_A and t_P, means for summing the respective distinct signals, means for forming a quotient of the sums of said distinct signals relating to the durations t_P with the sums of said distinct signals relating to the duration t_A, and counting means for fixing the number of signals counted at a number between at least 5 and at most 20 for each qualitative measurement and display of relaxation degree.

14. The apparatus defined in claim 10 wherein said means is a digital display.

15. The apparatus defined in claim 10 wherein said display means is an analog display.