Sleep detection using an adjustable threshold

A sleep detection device, comprising:

• a first sensor configured to sense a first sleep-related signal;
• a second sensor configured to sense a second sleep-related signal;
• and
• a sleep detector coupled to the first and the second sensors and configured to adjust a sleep threshold associated with the first sleep-related signal using the second sleep-related signal, and to detect a sleep condition by comparing the first sleep-related signal with the adjusted threshold, wherein one of the first sensor, second sensor and sleep detector comprises an implantable component.

A system for detecting sleep, comprising:

• means for adjusting a sleep threshold associated with a first sleep-related signal using a second sleep-related signal;
• means for comparing the first sleep-related signal to the adjusted threshold;
• and
• means for detecting sleep based on the comparison,
• wherein one of the means for adjusting, comparing or detecting comprises an implantable component.

A method of detecting sleep, comprising:

• sensing a plurality of sleep-related signals;
• defining a relationship between at least two of the sleep-related signals, the relationship associated with sleep detection;
• and
• detecting sleep using the sleep-related signal relationship, wherein at least one of sensing, defining, and detecting is performed at least in part implantably.