CHAPTER 3 - PERCEPTION Flashcards
define sensation
reception of stimulation from the environment and the initial encoding of that stimulation into the nervous system
for visual input what body part is used for sensation
eyes
name the photoreceptors of the eye
cones and rods
what is a saccade?
the quick movement of the eyes from one location to another
how long does a saccade last?
25-175 milliseconds
what is fixation?
the brief period when the eyes stop moving and process the visual scene
what is the area in the eye that has no cones or rods?
the blind spot
what happens to the sensory information when it reaches the blind spot
goes through the optic nerve to the brain
define perception
experiences resulting from stimulation of the senses
what occurs during perception?
process of interpreting and understanding information
what was George Sperling’s first experiment in 1960?
challenged the concept of perceptual span and introduced iconic memory
what is perceptual span?
the number if items one can report from a brief display that does not allow eye movement
what is the predicted perceptual span?
4.5 items
name the 2 kinds of reports Sperling had his participants do
whole and partial
what is a whole report?
trying to report everything that was presented
what is a partial report?
trying to report only the cued portion of the display
how did Sperling revise his experiment?
using digits and letters and had 3 kinds of report
what were the 3 new reports of Sperling’s revised?
whole, partial (spatial/row), and partial (categorial/type)
define a template
a pattern treated as an unanalyzed whole
what is a feature?
a separable element of a pattern
Describe Averbach and Coriell’s revised experiment
cued only one location to reduce memory demands even more
how did Averbach and Coriell replicate Sperling’s results?
using a bar marker and a circle
what were the conclusions of these experiences about perceptual span
perceptual span is not a good measure of what is perceived
what concluded about iconic memory?
an iconic image persists after an array disappears and it decays/is lost very rapidly
what kind of process is perception similar too?
the process of reasoning or problem solving and can change based on added information
what is the perceptual system’s job?
figure out what object created the image on the retina
what is the inverse projection problem?
the task of determining the object responsible for a particular image on the retina
what is viewpoint invariance?
the ability to recognize an object even when it is seen from different viewpoints
why does a scene have high level information?
has many objects and may have information that requires figuring out
what are the 2 types of information used by the human perceptual system?
environmental energy that stimulates receptors
knowledge and expectations that the observer brings to the situation
what is bottom-up-processsing?
the sequence of events from the eye to the brain
describe the events in bottom-up processing
looking at something to create an image on the retina
electrical signals go from the retina to the visual receiving area of the brain
what is top-down processing?
processing that originates from the brain/ the top of the perceptual system
what does top-down processing demonstrate?
addition of information to the foundation