Patent ID: 7806831

Claim:
A method of monitoring an individual for the occurrence of a particular sleep state condition of the individual, comprising: applying an external probe to an external surface at a peripheral body location on the individual's body for monitoring the peripheral vascular bed volume of the individual at said peripheral body location while applying a predetermined pressure field to the distal end of said peripheral body location, including its distal-most extremity, effective to prevent the occurrence of venous pooling within said peripheral body location, and thereby to produce an output from the probe corresponding to changes in the peripheral arterial bed volume at said peripheral body location; while the individual is in a sleep state, utilizing said probe to detect: (a) changes in the peripheral vascular bed volume of the individual at said peripheral body location, (b) amplitude changes in the probe output or time changes in the time course of the response pattern of the probe output, and (c) changes in the individual's pulse rate or amplitude, and to produce outputs corresponding to such changes; and determining the sleep state condition of the individual according to such changes detected by said external probe.