Sensation and Perception Flashcards
What is sensation?
when physical energy produces a change in specialized elements of the nervous system called “receptors”
ex. “I see a spot of light”
“I hear a buzz”
What is perception?
Sensations are interpreted and organized to give meaning to the objects or events that produced the sensation
ex. “I see the moon” “I hear a fire alarm”
What is transduction?
Turning a specific idea, thought into a general idea, thought, or experience.
How can we measure perception?
Present a stimulus, ask the person to describe it.
What is the field of psychophysics?
Study of relationship between physical stimuli and the resulting psychological experiences
What is absolute threshold?
Smallest level of energy required by an external stimulus to be detectable by human senses.
What is an action potential?
Action potentials are the fundamental units of communication between neurons.
When do neurons fire action potentials?
When stimulated can “all or none” response.
What does it mean to say that an action potential is an “all-or-none” event?
Neurons encode different intensities by changing their firing rate.
When measuring absolute threshold in a detection task, what introduces uncertainty into our decision as to whether or not a signal is present?
peoples BIAS
What do the terms hit, miss, false alarm, and correct rejection refer to in Signal Detection Theory?
Hit: presented and corrected
Miss: presented and incorrect
False Alarm: NOT presented said yes
Correct Rejection: NOT presented said no
What is Weber’s Law?
The just noticeable difference (JND) in the intensity of a stimulus is proportional to the intensity of the standard stimulus. ex. more likely to react to quiet commercial that suddenly doubles in volume than a commercial that only slightly increases in volume.
What is adaptation?
Our sensory systems are most responsive to changes in stimuli. The responsiveness to a stimulus decreases (adapts) when the stimulus remains constant.
What is the visual stimulus?
electromagnetic energy: energy emitted or reflected from objects in the form of electrical and magnetic waves.
-our visual receptors are sensitive to a small range of wavelengths
-we percieve different wavelengths as different colors.
What are the stages of visual information processing?
A ganglion cell responds when light falls on the point on the retina from which the cell recieves input.
