GENERAL PSYCHOLOGY
CHAPTER 4 NOTES
Please make sure you review the following terms/ concepts from this chapter. This includes not
just knowing the definitions, but also that you feel confident with your knowledge of the terms/
concepts and your ability to apply them critically.
Sensation – The stimulation of our sense organs by the outer world. Eyes are sensitive to
light waves, ears to sounds, skin to touch and pressure, tongues to tastes, and noses to odors.
Transduction – The conversion of physical into neural information. When cells in the retina
change light waves to neural energy, when hair cells in the inner ear change sound waves to
neural energy, when chemicals in the air bind to receptors in the nose, when food chemicals
stimulate taste buds on the tongue, and when pressure and temperature stimulate nerve cells
in the skin. In short, transduction is occurring when the outer world becomes the inner world.
Absolute threshold – The lowest intensity level of a stimulus a person can detect half of the
time. A common way to assess absolute thresholds is for a researcher to present stimuli, such
as light, of different intensities to a research participant. The intensity level that a participant
can see 50% of the time is that person’s absolute threshold for light. Imagine that six light
intensities, whose values are 150, 160, 170, 180, 190, and 200, are presented 10 times each.
Of these values, a participant detects the 180 value 50% of the time. Then 180 is this person’s
absolute threshold for this light stimulus.
Signal detection theory – The viewpoint that both stimulus intensity and decision-making
processes are involved in the detection of a stimulus. In signal detection research, a low-
intensity stimulus is presented on some occasions but not presented on other occasions.
Instead of having a 50% detection line, which is at threshold, signal detection experiments
present only a single, low-intensity stimulus. In signal detection the participant’s responses
create a profile of hits, misses, false alarms, and correct rejections. Hits and misses each
CHAPTER 4 NOTES
Please make sure you review the following terms/ concepts from this chapter. This includes not
just knowing the definitions, but also that you feel confident with your knowledge of the terms/
concepts and your ability to apply them critically.
Sensation – The stimulation of our sense organs by the outer world. Eyes are sensitive to
light waves, ears to sounds, skin to touch and pressure, tongues to tastes, and noses to odors.
Transduction – The conversion of physical into neural information. When cells in the retina
change light waves to neural energy, when hair cells in the inner ear change sound waves to
neural energy, when chemicals in the air bind to receptors in the nose, when food chemicals
stimulate taste buds on the tongue, and when pressure and temperature stimulate nerve cells
in the skin. In short, transduction is occurring when the outer world becomes the inner world.
Absolute threshold – The lowest intensity level of a stimulus a person can detect half of the
time. A common way to assess absolute thresholds is for a researcher to present stimuli, such
as light, of different intensities to a research participant. The intensity level that a participant
can see 50% of the time is that person’s absolute threshold for light. Imagine that six light
intensities, whose values are 150, 160, 170, 180, 190, and 200, are presented 10 times each.
Of these values, a participant detects the 180 value 50% of the time. Then 180 is this person’s
absolute threshold for this light stimulus.
Signal detection theory – The viewpoint that both stimulus intensity and decision-making
processes are involved in the detection of a stimulus. In signal detection research, a low-
intensity stimulus is presented on some occasions but not presented on other occasions.
Instead of having a 50% detection line, which is at threshold, signal detection experiments
present only a single, low-intensity stimulus. In signal detection the participant’s responses
create a profile of hits, misses, false alarms, and correct rejections. Hits and misses each
