Modules 16,17,18 Flashcards
What is sensation
The process by which our sensory receptors and nervous system receive and represent stimulus energies from our environment
Define perception
The processes of organizing and interpreting sensory information, enabling us to recognize meaningful objects and events
Define bottom-up processing
Analysis that begins with the sensory receptors and works up to the brain’s integration of sensory information.
Define top-down processing
Information processing guided by higher-level mental processes, as when we construct perceptions drawing on our experience and expectations.
Provide na example of both bottom up and top down processing:
Ex: bottom up processing allows the sensory systems to observe the lines and colors of flowers, while top down processing interprets what these senses detect
What is selective attention
The focusing of conscious awareness on a particular stimulus
What is inattention blindness
Failing to see visible objects when our attention is directed elsewhere.
What is change blindness
Failing to notice changes in the environment
What do our senses help us to do?
Receive sensory stimulation, often using specialized receptor cells
Transform that stimulation into neural impulses
Deliver the neural information to our brain
What is transduction
Conversion of one form of energy into another. In senseation, the transforming of stimulus energies, such as sights, sounds, and smells, into neural impulses our brain can interpret.
What is psychophysics
The study of relationships between the physical characteristics of stimuli, such as their intensity, and our psychological experience of them.
What are absolute thresholds
The minimum stimulation needed to detect a particular stimulus 50% of the time.
Ex: Detecting a particular light, sound , pressure, taste, or odor
What is signal detection theory
A theory predicting how and when we detect the presence of a faint stimulus (signal) amid background stimulation (noise). Assumes that there is no single absolute threshold and that direction depends partly on a person’s experience, expectations, motivation, and alertness.
-Tries to understand why people respond differently to the same stimuli
What is subliminal
Below one’s absolute threshold for conscious awareness
What is prime
The activation, often unconsciously, of certain associations, thus predisposing one’s perception, memory, or response.
What is The difference threshold
The minimum difference between two stimuli required for detection 50 percent of the time. We experience the difference threshold as a just noticeable difference (minimum difference a person can detect between two stimuli half the time)
What is Weber’s law
The principle that for an average person to perceive a difference two stimuli must differ by a constant minimum percentage, not a constant amount)
What is Sensory adaptation
Diminished sensity as a consequence of cosntant stimulation
-Going into a loud movie theater, you will eventually get used to it
What is a perceived set
A mental predisposition to perceive one thing and not another
Ex: stereotypes about ethnicity or race
What is wavelength
Distance from one wave peak to the next, which determines the hue (dimension of color that determined by the wavelength of light; what we know as the color names blue, green, and so forth.
What is intensity
amount of energy in light waves. This influences brightness
Describe the process in which light enters the eye:
Light enters the eye through the cornea, which protects the eye and bends light for focus
Light passes through the pupil (adjustable opening in the center of the eye through which light enters.)
The pupil controls the size of the iris (ring of muscle tissue that forms the colored portion of the eye around the pupil and controls the size of the pupil opening.)
Behind the pupil is the lens (transparent structure behind the pupil that changes shape to help focus images on the retina)
Retina is the light-sensitive inner surface of the eye, containing the receptor rods and cones plus layers of neurons that begin the processing of visual information
The lens focuses the rays by changing the curve in a process called accomodation
Remember: the retina doesn’t see a whole image, but rather they convert particles of light energy into neural impulses
What are rods
Retinal receptors that detect black, white, and gray; necessary for peripheral and twilight vision, when cones don’t respond
What are cones
Retinal receptor cells that are concentrated near the center of the retina and that function in daylight or in well-lit condition. The cones detect fine detail and give rise to color sensations
