12 - Visual Perception Flashcards
What are letter features?
Lines
Curves
Etc.
What experiment did Riggs et al perform in 1953?
Developed special contact lens that projected images directly onto the retina
Image would be projected directly onto retina no matter where the eye was “looking”
Images would fade after a few seconds
What did Riggs et al want to learn (1953)?
How we processed the info coming directly at us
What did Riggs et al find in their 1953 experiement?
4
Letters and shapes would fade due to neural fatigue.
However they would fade in a organized pattern that made sense (shapes, letters, words)
Words would NEVER fade into nonwords
Letters would NEVER fade into non-letter/numbers
What did Hubel & Wiesel study in 1962?
How animals recorded neural activity in the visual cortex
What did Hubel & Wiesel learn from their 1962 experiment?
3
Some neurons are specialized for feature detection (Feature Detectors)
Feature Detector Neurons that respond to specific features. They only detect certain orientations ( / - | \ )
This is only seen when the object is in the center of our visual field
What award did Hubel & Wiesel receive in the 1980s?
Nobel Prize
Most letters have ___ basic features.
In English, the average has ___ letters.
5
5
Typical reading speed is about _____ words/minute.
That’s over ______ features a second.
250
100
Is reading a combination of top-down and bottom-up processing?
Yes
Top-down influences are obvious in _______.
Top-down processing helps us make sense out of ______ and ______.
Context effects
Ambigiuous info
Optical illusions
Does top-down processing influence our perception of words/letters - especially in contextual situations?
Yes
Can we interpret things better when “noise” is applied (ink blots, etc.)?
Yes
Will context help us interpret distorted or ambiguous bottom-up information?
Yes
Does top down processing allow us to read different handwritings, fonts, etc.?
Yes
What is a connectionist model?
All the parts of a theory are interacting with each other instead of working individually
What model of visual perception did MeClelland & Rumelhard create in 1981?
Interactive-Activation Model
What is the Interactive-Activation Model?
It is a connectionist (PDP) model
Words are presented acorss different levels
(Whole words, letters, visual features)
These levels interact with one another
What can the Interactive-Activation Model explain?
This modal can explain how we read ambiguous information
It cuts out the nonsense information and leaves us with real words
What theory of reading did Coltheart et al create in 1989 & 1993?
Dual Route Model of Reading
What is the Dual Route Model of Reading?
There are two routes to reading words
Direct Route
Indirect Route
What is the direct route in Coltheart’s Dual Route Model of Reading?
Orthographic
Reading by eye
Whole word reading
What is pathway of understanding for the direct route (in Coltheart’s Dual Route Model of Reading)?
Letter Units ->
Orthographic Lexicon (letters) ->
Semantics Lexicon (meaning) ->
Phonological Lexicon (sound)
What is the indirect route in Coltheart’s Dual Route Model of Reading?
Phonological
“Reading by Ear”
Sounding out
Used for new words and non-words
What is pathway of understanding for the indirect route (in Coltheart’s Dual Route Model of Reading)?
Letter Units ->
Spelling/Sound Conversion->
Speech Output
What are Connectionist Models of Reading?
There are three different units being processed
All interact with each other
The same process is used for ALL words
Assumes that we always process phonology when we read
(For non words the orthographic and phonological units interact but there is no need for the semantic unit since there is no meaning to attach)
What are the three different units being processed in Connectionist Models of Reading?
Orthographic (Letter) Units
Phonological Units
Semantic Units
What is the Stroop Effect?
Participants are asked to name the color of the text NOT what the text says
What does the Stroop Effect show us?
Shows that reading is so automatic that we can’t even stop it even if we try
Even when you become good at this you still have to slow down significantly
How is the Stroop Effect performed with bilinguagals?
In bilinguagls, may ask for the color in English and have the color names written in their other language
What is the Stroop Effect?
Participants are asked to name the color of the text NOT what the text says
What does the Stroop Effect show us?
Shows that reading is so automatic that we can’t even stop it even if we try
Even when you become good at this you still have to slow down significantly
How is the Stroop Effect performed with bilinguagals?
In bilinguagls, may ask for the color in English and have the color names written in their other language
What did Reicher discover in 1969?
The Word Superiority Effect
What is the Word Superiority Effect?
We recognize letters better when they are in a word. It is harder when the letter is viewed alone.
What did Reicher want to learn?
How people perceived letters when presented in different contexts
In what contexts did Reicher place the target letter?
Alone
In a Word
In a Non-Word
How was the Word Superiority experiment performed?
Words were presented for 50 msec.
Participants asked for the last letter
In the Word Superiority experiment, in what context did the participants perform best?
Participants performed best when the letter was in a real word. (The letter was easiest to recognize in context.)
Note: it can be hard to recognize letters when there is no context
