Top-down processes
The fact that listeners rarely notice mispronunciation of phonemes in the context of a sentence
How does mispronunciation relate to top-down processing
Information processing takes place through the excitatory and inhibitory interactions of a large number of simple processing units, each working continuously to update its own activation on the basis of the activations of other units to which it is connected
What is the trace model
a 0.3 mm diameter rod-free area with very thin, densely packed cones.
What is fovea centralis
Approximately 6 - 8 letters
Fovea
Foveal region uptakes visual info to verify letters (hence words), parafoveal allows for few more letter spaces and maybe next word, and the peripheral vision stabilizes the visual fixation
How do fovea, parafovea, and periphery combine for visual processing?
A phenomenon whereby a person listening to speech recordings in which phonemes have been replaced by white noise or have otherwise been made inaudible does not notice the interruption
What is the phoneme restoration effect?
Perception is an iterative process, the iteration involves articulation
What is analysis-by-synthesis?
provides the sharpest vision
what is fovea?
~15 letters to the right and left
Parafovea
Sudden, rapid, controlled movements that allow the eye to move to identify outside perception span; when eye briefly stops at the region, that’s the fixation where it’s up taking info
What are saccades?
When a categorical boundary shifts towards a word from a non-word
What are perceptual boundaries?
feature, phoneme, and word
What are the three levels of interactive units of the trace model?
previews foveal information
What is parafovea?
Extends to the end of line
Periphery
Use part of perceptual span to see end of the word
When you fixate too early
The superiority of the letters; faster to identify a letter in the context of a word than a non-word
What is the word superiority effect?
Claims that the invariance isn't in the speech signal but in the speaker's gestures (motor commands of articulatory mechanisms like the vocal tract moving). Hear sound differently based on knowledge of how you produce that sound (implicit knowledge); the gesture (how you produce sound in that context) is where the invariance is
What is the motor theory of speech perception?
reacts to motion; gives "blob" information
what is periphery?
Equivalent to 3-4 letter spaces in typical texts.
What are the reading consequences of 1 degree of visual angle?
Lose crucial information about the word /start of word
When you fixate too late or in the centre
a categorical change in auditory perception induced by incongruent visual speech, resulting in a single percept of hearing something other than what the voice is saying.
What is the McGurk effect?
receptors for high spatial resolution
what are cones good for?
The size of the effective vision, is 3-4 letter spaces to the left of fixation and 14-15 letter spaces to the right
Perceptual span
Will get the first part of the word, and get as much info right of that (allowing you to incorporate the unique display)
When you fixate off-centre