Sensation and Perception Flashcards
Sensation
Conversion of physical, electromagnetic, auditory, and other info from internal and external environment into electrical signals in nervous system
Perception
Processing of sensory information to make sense of its significance
Absolute threshold
minimum of stimulus energy that is needed to activate a sensory system
Threshold of conscious perception
minimum of stimulus energy that creates a signal large enough in size and long enough in duration to be brought into awareness
Difference threshold or just noticeable difference
Minimum difference in magnitude between two stimuli before one can perceive this difference
Weber’s law
The JND for a stimulus is proportional to the magnitude of the stimulus and that this proportion is constant over most of the range of possible stimuli
Signal detection theory
Effect of non-sensory factors (experiences, motives, expectations) on perception of stimuli
Adaptation
decrease in response to a stimulus over time
Cornea
Gathers and filters incoming light
Iris
Colored part of the eye
Divides into anterior and posterior chambers
Lens
Refracts incoming light to focus it onto the retina and is held in place by suspensory ligaments connected to ciliary muscle
Retina
Contains rods (dim light) and cones (color)
Contains mostly cones in the macula (central visual field)
Fovea
At the center of the macula
Contains only cones
Most precise vision
Parallel processing
Ability to analyze and combine information simultaneously regarding color, shape, and motion
Parvocellular cells
Detect shape
High spatial resolution