psychology vocabulary chapter 5-sensory adaptation
signal direction theory
a theory predicting how and when we detect the presence of a faint stimulus amid background stimulation. Assumes there is no single absolute threshold and that detection depends partly on a persons experience, expectations, motivation, and level of fatigue
bottom-up processing
analysis that begins with the sensory receptors and works up to the brains integration of sensory information
Subliminal
below ones absolute threshold for conscious awareness
sensory adaptation
diminished sensitivity as a consequence of constant stimulation
top-down processing
information processing guided by higher-level mental processes, as when we construct perceptions drawing on our experience and expectations.
priming
the activation, often unconsciously of certain associations thus predisposing ones perception, memory, or response.
difference threshold
the minimum difference between two stimuli required for detection 50% of the time. We experience the difference threshold as a just noticeable difference.
absolute threshold
the minimum stimulation needed to detect a particular stimulus 50% of the time
webers law
the principle that, to be perceived as different, two stimuli must differ by a constant minimum percentage
sensation
the process by which our sensory receptors and nervous system receive and represent stimulus energies from our environment.
perception
the process of organizing and interpreting sensory information enabling us to recognize meaningful objects and events.
Psychophysics
the study of relationships between the physical characteristics of stimuli, such as their intensity and our psychological experience of them