Sensation Practice Test

Weber’s law: the minimum detectable brightness is a constant proportion of background light, so 50% detection does not define it.

Absolute threshold: the minimum brightness intensity detected correctly on 50% of trials, estimated by varying the stimulus level.

Perceptual set: the participant’s expectations about brightness determine detection, so the researcher is measuring a cognitive bias.

Difference threshold: the smallest brightness change detected 50% of the time, which requires comparing two intensities, not gradual onset.