Sensory thresholds refer to the minimum level of stimulus intensity required for a sensory receptor to detect a change in the environment. This concept applies to all five senses: sight, hearing, taste, touch, and smell. For example, the absolute threshold is the smallest amount of stimulus that can be detected, while the difference threshold (or just noticeable difference) is the smallest change in stimulus intensity that can be perceived. These thresholds can vary among individuals and can be influenced by factors such as age, health, and environmental conditions. Understanding sensory thresholds is important in fields like psychology and neuroscience, as it helps researchers study how humans perceive and interact with the world around them.