Quiz 2 Flashcards
(91 cards)
Bottom up processing
processes that directly shaped by stimulus
Can bottom up processing explain everything?
NO
-Apperceptive agnosia: (V1) impaired early vision, unable to recognize basic features
-Associative agnosia: impaired late vision, can see object/draw, but can’t recognize/name
How is perception constructive
affected by assumptions about the context
(e.g. stimulus + env)
Top-down processing
knowledge/expectations that influence and enhance interpretation of sensory input
Examples of knowledge/expectations we use in top down processing
Context and Experience shape perception
Why are features important?
Helps in visual search tasks (examine a display and judge whether target is present)
-slower w/ combination search
Word Recognition
Tachistoscopic presentation (flash word quickly, then cover w/ random word and then ask about recognition of words)
Word recognition is better with which conditions?
-high frequency words (recognized in tachistoscopic)
-primed high frequency words
-primed low frequency words over unprimed low frequency words
as long as high frequency and/or primed
How do we recognize words?
-word superiority effect
-well formedness
-feature nets
Word Superiority effect
remember/recognize entire words better than single letters
Feature nets
-driven by bottom-up (sensitive to external stimuli) and top down (recency effect/priming)
-can be used w/ well-formedness
Well-formedness
how closely letter sequence conforms to typical patterns of spelling in language
(e.g. HZYQ vs FIKE vs HIKE)
-may be prone to errors because of this
Detectors of feature nets
- feature
- letter
- bigram
- word
-each receptor has starting activation level (affected by recency & frequency)
-input increases activation
-firies when response threshold reached
-NOT neuron (rather could be represented by network of neurons/neural tissue)
important aspects of feature nets
-knowledge is distributed (increase neuronal firing=correct)
-sacrifice perfect accuracy for efficiency
-more advanced feature nets have connected mechanisms (top-down, bottom up. lateral connections)
Feature nets for objects
- feature detectors
- geon detectors
- geon assemblies
- object model
(use about 30 geons to create objects)
Face perception
face inversion effect=something special about faces
-make more errors w/ inverted faces compared to inverted houses
-more extensive experience, unique processing strategy
Prosopagnosia
cannot recognize individuals face- but have good vision+memory
Super-recognizers
identify faces amazingly well (recognize years later)
Perception (imagery) and brain areas
-areas (face-inferotemporal, places-hippocampus) used for early visual processing are ALSO active during visualization imagery
-disruption (natural or TMS) affects vision AND imagery
Individual differences in imagery
change in frequency is due to the level of vividness of imagery (more vividly you image=more change in frequency)
Visual imagery
involves experience of seeing
Spatial imagery
involves moving through space
Visual VS Spatial imagery
Strengths of Visual: career in arts, emotional processing
Strengths of Spatial: science, reliving memories
Attention
- cognitive mechanisms that combine to help us select, modulate, and sustain focus on information that might be most relevant for behaviour.
- capacity-limited
- directed externally or internally