CHAP 2 Sensation and Perception Flashcards
What is the primary difference between sensation and perception?
Sensation is the conversion of physical stimuli into electrical signals; perception is the processing of these signals to understand their significance.
What are sensory receptors?
Nerves that respond to stimuli and trigger electrical signals.
What are sensory neurons associated with?
Sensory ganglia, which are collections of cell bodies outside the central nervous system.
What do projection areas in the brain do?
Further analyze the sensory input.
Name some common sensory receptors.
- Photoreceptors
- Hair cells
- Nociceptors
- Thermoreceptors
- Osmoreceptors
- Olfactory receptors
- Taste receptors
What is a threshold in sensory perception?
The minimum stimulus that causes a change in signal transduction.
Define absolute threshold.
The minimum amount of stimulus energy needed to activate a sensory system.
What is the threshold of conscious perception?
The minimum stimulus energy that creates a signal large enough and long enough to be brought into awareness.
What is the difference threshold or just-noticeable difference (jnd)?
The minimum difference in magnitude between two stimuli before one can perceive this difference.
State Weber’s law.
The jnd for a stimulus is proportional to the magnitude of the stimulus, and this proportion is constant over most of the range of possible stimuli.
What does signal detection theory examine?
The effects of nonsensory factors like experiences, motives, and expectations on the perception of stimuli.
What are the four possible outcomes in a signal detection experiment?
- Hits
- Misses
- False alarms
- Correct negatives
What does adaptation refer to in sensory perception?
A decrease in response to a stimulus over time.
Fill in the blank: Sensation is the conversion of physical, electromagnetic, and other information into _______.
[electrical signals in the nervous system]
True or False: The absolute threshold is the same as the difference threshold.
False
What is the primary function of the eye?
To detect light in the form of photons
What role does the cornea play in vision?
Gathers and filters incoming light
What two muscles are contained in the iris?
- Dilator pupillae
- Constrictor pupillae
What is the function of the lens in the eye?
Refracts incoming light to focus it on the retina
What holds the lens in place?
Suspensory ligaments connected to the ciliary muscle
What does the ciliary body produce?
Aqueous humor
Where does aqueous humor drain?
Through the canal of Schlemm
What are the two types of photoreceptor cells in the retina?
- Rods
- Cones
What do rods detect?
Light and dark
