Signal detection theory differs from the absolute threshold because it addresses stimuli that are:

1. Laboratory thresholds are measured under ideal, quiet conditions. 2. Real environments are noisy, so detection becomes a judgment rather than a measurement. 3. The ability to identify a stimulus when it is embedded in a distracting background is called signal detection theory. 4. That framing allows for both misses and false alarms. 5. A stimulus far above threshold poses no detection problem at all. _Source: OpenStax Psychology 2e (CC BY 4.0), Ch 5 'Sensation and Perception', sections 5.1-5.6_