Final answer:
The absolute threshold is the minimum stimulus energy required for detection, whereas the difference threshold is the minimum change in stimulus needed to notice a difference. These concepts are key to distinguishing between detection, as with the absolute threshold, and discrimination, as with the difference threshold or Weber's law in sensory perception.
Step-by-step explanation:
Differences between Detection and Discrimination Thresholds
The concepts of absolute threshold and difference threshold are central to understanding the differences between detection and discrimination in the context of sensory stimuli. The absolute threshold refers to the minimum amount of stimulus energy that must be present for a stimulus to be detected 50% of the time. For example, on a clear night, a person might detect a candle flame 30 miles away, demonstrating the remarkable sensitivity of our sensory receptors.
In contrast, the difference threshold, or just noticeable difference (jnd), describes the minimum amount of difference in stimulus energy required to detect a change in the stimulus 50% of the time. The difference threshold varies depending on the intensity of the initial stimulus. This concept is encapsulated by Weber's law, which posits that the difference threshold is a constant fraction of the original stimulus. For instance, a minor increase in illumination might be more noticeable in a dark movie theater than in a brightly lit basketball arena.
Stimulus discrimination is also an important learning process whereby organisms such as humans and animals respond differently to various similar stimuli, enabling them to react appropriately to their environment. For example, Pavlov's dogs only responded to the specific tone associated with feeding, not to other similar tones.