Psych Chapter 6 09/26/2013
Chapter 6: Sensation and Perception
Study of how the world out there gets in…how we construct internal representations of the external world.
Sensationrefers to the stimulation of the sensory organs by physical energy from the external world,
and the conversion of this energy into neural signals.
Transductionpage 218 in book.
Perceptionrefers to our interpretation of what we sense based on experience, expectations, and
Sensation and perception are not the same. For example, people who suffer from prosopagnosia cannot
perceive human faces, but they can perceive objects.
Sensing the World: Basic Principles
Absolute Thresholdthe minimum stimulation necessary to detect physical stimulation half the time; that is,
a particular light, sound, pressure, taste, or odor.
Psychophysicsstudy of the relationship between physical characteristics of physical stimuli and our
perceptual experiences of them, and makes use of signal detection to measure absolute thresholds and
other properties of sensation and perception.
Stimuli below the absolute threshold are subliminal and we are influenced by subliminal stimulation.
However, effects of subliminal stimulation are fleeting. And there’s no evidence for powerful, enduring
effects on behavior.
Wavelengthrefers to the distance between one wave peek and the next, and determines hue (color).
Intensityrefers to the amplitude of the light wave (its height) and determines brightness.
The light enters the eye through the cornea the clear coating that protects the eye. The light passes
through the pupil. A small adjustable opening surrounded by the iris a colored muscle that gives your eyes
their color and dilates or constricts in response to light intensely through a process called accommodation.
The lens focuses the light on the retina.
Retinathe light sensitive inner surface of the eye containing receptor rods and cones in addition to layers of
other neurons the process visual info.
Conesenable color vision and