Module 17 Flashcards
Basic Principles of Sensation and Perception
What is sensation?
the process by which our sensory receptors and nervous system receive and represent stimulus energies from our environment
What is perception?
the process of organizing and interpreting sensory information, enabling us to recognize meaningful objects and events
What is bottom up processing?
starts at the sensory receptors and works up to higher levels of processing
What is top down processing?
constructs perceptions from the sensory input by drawing on our experience and expectations
What three steps are basic to all our sensory systems?
R - Receive sensory stimulation
T - Transform that stimulation into neural impulses
D - Deliver the neural information to our brain
What is transduction?
conversion of one form of energy into another
What is psychophysics?
the study of relationships between the physical characteristics of stimuli, such as their intensity, and our psychological experience of them
What is absolute threshold?
the minimum stimulation needed to detect a particular stimulus 50% of the time
Detecting a weak stimulus depends on what two things?
- the signal’s strength
2. our psychological state (experience, expectations, motivation, alertness)
What is signal detection theory?
a theory predicting how and when we detect the presence of a faint stimulus amid background stimulation.
What does signal detection theory assume?
there is no single absolute threshold and that detection depends partly on a person’s expectations, experience, motivation, and alertness
What is an example of a study for signal detection theorists?
Why do exhausted parents notice the faintest whimper from a newborn’s cradle while failing to notice louder, unimportant sounds.
What does subliminal mean?
below one’s absolute threshold for conscious awareness
True or False. Under certain conditions, you can be affected by stimuli so weak that you don’t consciously notice them.
True
What does priming mean?
the activation, often unconsciously, of certain associations, thus predisposing one’s perception, memory, or response
What three factors will make it more likely that you correctly detect a text message?
- Expecting it.
- You see the message and respond.
- You are alert
When will a stimulus reach our consciousness?
when it triggers synchronized activity in several brain areas
True or False. Much of our information processes occur only when we concentrate upon them.
False. Much of this occurs automatically, out of sight, off the radar.
What is difference threshold?
the minimum difference between two stimuli required for detection 50% of the time
What is another name for difference threshold?
just noticeable threshold
True or False. The difference threshold decreases with the size of the stimulus.
False. it increases
What is Weber’s law?
the principle that, to be perceived as different, two stimuli must differ by a given percentage (rather than a given amount)
What is sensory adaptation?
diminished sensitivity as a consequence of constant stimulation
Why is it that after wearing shoes for a while, you cease to notice them?
The shoes provide constant stimulation. Sensory adaptation allows us to focus on changing stimuli.
