The study of relationships between the physical characteristics of stimuli, such as their intensity, and our psychological experience of them.
The minimum stimulation needed to detect a particle
Signal Detection Theory
A theory predicting how and when we detect the presence of a faint stimulus amid background noise. Assumes there is no single absolute threshold and that detection depends partly on a person's experience, expectations, motivation, and alertness.
below one's absolute threshold for conscious awareness
the activation, often unconsciously, of certain associations, thus predisposing one's perception, memory, or response.
the minimum difference between two stimuli required for detection 50% of the time. We experience the difference threshold as a just noticeable difference.
the principle that, to be perceived as different, two stimuli must differ by a constant percentage (rather than a constant amount.)