Chapter 3 - Perception Flashcards
-Perception is:
- experience resulting from stimulation of the senses. Basic Concepts:
- perceptions can change based on added information
- involves a process like reasoning or problem solving
- perceptions occur in conjunction with actions
-It is possible that true human perceptual processes are
unique to humans
-Attempts to create artificial forms of perception (machines) have been met with limited success and each time have had problems that could not be solved
Why is it so Difficult to Design a Perceiving Machine?
-Inverse Projection Problem
- refers to the task of determining the object responsible for a particular image on the retina
- involves starting with the retinal image and then extending outward to the source of that image
-Objects can be hidden or blurred
-people can often identify objects that are obscured and therefore incomplete, or in some cases objects that are blurry
-Objects look different from different viewpoints
-viewpoint invariance
Approaches to Understand Perception
- Direct perception theories
- bottom-up processing
- perception comes from stimuli in the environment (starts form the “bottom”)
- parts are identified and put together, and then recognition occurs
- Construction perception theories
- top-down processing
- people actively construct perceptions using information based on expectations
- start from the “top” (brain)
The Complexity of Perception
-Bottom-up processing
- perception may start with the senses
- incoming raw data
- energy registering on receptors
Top-down processing
- perception may start with the brain
- person’s knowledge, experience, expectations
Hearing Words in a Sentence
-when you hear words in a sentence spoken or in a foreign language, your ability to pick out or understand words based on context demonstrates top-down processing (e.g., listening to a baseball game that is broadcast in Spanish may make it easier to hear players names or certain “baseball-related” words)
(speech segregation)
-the ability to tell when one-word ends, and another begins
-transitional Probabilities
the likelihood that one sound will follow another within a word
-Statistical probabilities
every language has transitional probabilities for different sounds, and the process of learning about transitional probabilities and about other characteristics of language
Experiencing Pain
-Direct Pathway Model
- an early model that emphasized nociceptors that would send pain messages directly to the brain
- A bottom-up processing model
- more recent models have found that expectations, attentions and distraction can affect how we experience pain in a “top-down” manner
- The placebo effect
- attention, play games during bandages change
Bottom-up Processing: Behavioral
-Recognition-by-components theory:
- we perceive objects be perceiving elementary features
- Geon’s: three-dimensional volumes
- objects are recognized when enough information is available to identify objects; geons
Geons
- discriminability: geons can be distinguished from other geons from almost all viewpoints
- resistance to visual noise: geons can be perceived in “noisy” conditions
- distinct: 36 different geons have been identified
Treisman’s Feature Integration theory (FIT) – COGLAB 3 – Illusory Conjunctions
-Visual perception and visual attention Identification of objects in the world involves two stages:
- A pre-attentive stage that automatically computes basic features
- An attentive stage that binds together the basic features to form objects Identification of objects depends on what else is also visible
-Visual search can be used for two basic purposes: First, to identify the basic features of visual perception that are proceeded pre-attentively. Second, to investigate the nature of attentive stage.
Feature integration theory (FIT)
- Pre-attentive stage
- Automatic
- No effort or attention
- Unaware of process
- Object analyzed into features
-R.M. – Ballint’s syndrome
- inability to focus attention on individual objects
- high number of illusory conjunctions reported
-Feature integration theory (FIT)
- mostly bottom-up processing
- top-down processing influences processing when participants are told what they would see
- top-down processing combines features with feature analysis to help one perceive things accurately