Unit 3: Sensation and Perception Flashcards
Sensation
The process by which our sensory receptors and nervous system receive and represent stimulus energies from our environment.
Perception
The process of organizing and interpreting this information, enabling recognition of meaningful events.
Bottom-up processing
Bottom-up processing refers to processing sensory information as it is coming in.
For example, if you see an image of an individual letter on your screen, your eyes transmit the information to your brain, and your brain puts all of this information together.
Top-down processing
Top-Down Processing is the idea that our brains form an idea of a big picture first from previous knowledge and then break it down into more specific information.
An example of this is stubbing your toe on a chair, the pain receptors detect pain and send this information to the brain where it is processed.
Selective Attention
A very limited portion of incoming information, blocking out much and often shifting the spotlight of our attention from one thing to another.
Inattentional blindness
Inattentional blindness a failure to notice unexpected but perceptible stimuli in a visual scene while one’s attention is focused on something else.
What three steps are basic to all our sensory systems?
Our senses
(1) receive sensory stimulation (often using specialized receptor cells),
(2) transform that stimulation into neural impulses, and
(3) deliver the neural information to the brain.
Transduction
The process of converting one form of energy into another.
Psychophysics
Study the relationships between stimuli’s physical characteristics and our psychological experience of them.
Absolute threshold
The minimum stimulation is necessary for us to be consciously aware of it 50 percent of the time.
Signal detection theory
Predicts how and when we will detect a faint stimulus amid background noise.
Difference threshold
The minimum stimulus difference we can pick out 50 percent of the time.
Weber’s law
States that two stimuli must differ by a constant percentage (not a constant amount) to be perceived as different.
Sensory adaptation
(our diminished sensitivity to constant odors, sights, sounds, and touches) focuses our attention on informative changes in our environment.
Basilar membrane
Found in the cochlea; it forms the base of the organ of Corti, which contains sensory receptors for hearing.
Define receptor cell-
Protein molecules inside the target cell or on its surface receive a chemical signal.
What does a rod do?
Specialized photoreceptors that work well in low light conditions are involved in our vision in a dimly lit environment as well as our perception.
What does a cone do?
Receptor cells help us see fine details of things and tend to help us see in situations where there is light or daylight.
What is important about the fovea?
It is responsible for sharp central vision, which is necessary for humans for reading, watching, driving, and things that require consistency.
What is the place where the ganglion cells’ axons leave the eye?
They exit the retina through a circular region in its nasal part called the optic disk, where they bundle together.
What lobe processes visual information?
Occipital Lobe
Explain the trichromatic theory of color vision-
There are three classes of cone receptors subserving color vision.
The three primary colors are the base of all colors.
Explains Colorblindness
Explain the opponent-process theory of vision-
One member of the color pair suppresses the other color.
For example, we do see yellowish-greens and reddish-yellows, but we never see reddish-green or yellowish-blue color hues.
Explains Afterimages
What is the vestibular sense and what parts of the ear are important to it?
A sensory system that provides the leading contribution to the sense of balance and spatial orientation for the purpose of coordination of the body’s movements.
The major sensory organs of the vestibular system are located next to the cochlea in the inner ear.
