perception Flashcards
what is a local level of processing
details and parts of the whole
what is the global level of processing
the whole picture
what is viewpoint invariant
object recognition does not depend on viewpoint
doesn’t matter what angle looked at from, processes the same
what is viewpoint dependent
object recognition does depend on viewpoint
within category discrimination
what are the 3 different types of pattern recognition theories
template
prototype
feature
template theories
selfridge and neisser 1960
selfridge and neisser 1960
template theories
template theories
explanation
patterns in real world recognised but matching those stored in templates
prototype theories
rosch 1975
rosch 1975
prototype theories
prototype theories
explanation
we store prototypes instead of templates
the most typical member of a category
feature theories
jaun and duin 2004
jaun and duin 2004
feature theories
feature theories
explanation
patterns consist of set of features of attributes
feature theories
neisser 1964
find the letter z in 2 lists
list 1 was more difficult to identify the letter z because it shares more features with the other letters e.g. straight lines
navon 1977
global and local
global and local
navon 1977
navon 1977
study
performance speed was slowed when asked what the small letters was when the large letter differed
however
decision speed with the large letter was not influenced by the small letter
i.e. when the small letters differed, decision speed for the large letter was not slowed
global affects local but not visa versa
dalrymple, kingstone and handy 2009
replicated navon
replicated navon
dalrymple, kingstone, handy 2009
replicated navon
study
when the small letters were densely packed, it replicated Navon but when the spacing between the letters were bigger, processing was faster at the local level than the global letter
biederman 1987
recognition of components
recognition of components
biederman 1987
recognition of components
explanation
we can construct everything in our world form a set of 36 shapes called geons
geons are view-invariant
they are easily discriminable from each other
complex shapes are more than one geon connected
4 steps pf object recognition
edge extraction
detection of non-accidental properties/parsing of regions by concavity
determination of components
matching components to object representations
convex vs concave
the invariant properties can still be detected even why only parts of edges are visible
provided the concavities are preserved, the object can still be identified
what is apperceptive agnosia
a failure in recognition due to a failure of perception
cannot copy shapes when asked to do so
what is associative agnosia
perception occurs but recognition does not occur
can copy shapes but cannot identify the objects
why are faces important in cognition
recognising faces requires ‘within-category’ discrimination
we are very good and fast at this discrimination
what is configural processing
in relation to faces
whole/holistic processing
position of features in relation to each other
doesnt matter what you do to a face e.g. blur, we still recognise it
what is featural processing
in relation to faces
parts/piecemeal
using the features of the face e.g. nose
key findings in face processing
yin 1969
face inversion effect
key findings in face processing
face inversion effect
yin 1969
key findings in face processing
face inversion effect
study
performance for upright is always better than for inverted
but
inversion disrupts processing for faces more so than for other types of stimuli e.g. stickmen
inversion affects configural processing but not featural
key findings in face processing
whole over part effect
tanaka and farah 1993
key findings in face processing
tanaka and farah 1993
whole over part processing
key findings in face processing
whole over part processing
study
p’s are significantly more accurate at recognising features when they are embedded in a face
suggests that processing of faces is holistic not simply a series of features/parts
supports global/top down processing
key findings in face processing
distinctiveness effect
bruce et al 1994
key findings in face processing
bruce et al 1994
distinctiveness effect
key findings in face processing
distinctiveness effect
study
distinctive faces are recognised better than less distinctive faces
key findings in face processing
the thatcher effect
thomson 1980
key findings in face processing
thomson 1980
the thatcher effect
key findings in face processing
the thacther effect
study
subtle rational changes between features are harder to identify in inverted faces
own effects?
people are better at recognising faces of their own race, the same age as them, the same gender as them and the same species as them
is face recognition innate?
according to johnson 2005, newborns visual ability is different to that of an adults
adults see more detail and need less contrast to do so
when we see a familiar face we use face memory
when we see an unfamilar face we need information on emotion and gender in order to know how to interact
is face recognition innate?
johnson et al. 1991
infants tested one hour after birth found that they orient towards face-like stimuli compared to scrambled faces
is face recognition innate?
simion et al 2002
babies fixated longer on patterns with most elements in their top half
free space model
valentine 1991, 2016
valentine 1991 2016
free space model
free space model
explain
we compare any face to an average face and put on this model depending on features
explains why it is more difficult to remember average looking faces
faces are easy to recognise when difference from mean is exaggerated
what is prosapagnosia
inability to recognise faces
prosopagnosia can be developmental or aquired
developmental- present from birth and is a developmental disorder
never develop the face recognition system
tends to run in families
aquired-from a brain injury
had typical system before
prosopagnosia 3 inclusionary criteria
difficulty with faces in every day life
impairment on at least 2 measures of face familiarity
lesions confirmed by CR or MRI scans
what is anomia
can recognise face but cannot remember name
patient PG
young et al 1988
young et al 1988
patient PG
patient PG
explain
damage to RH impaired in structural encoding of faces
patient est
flude et al 1989
flude et al. 1989
patient est
patient est
explain
can perceive and encode faces but cannot retrieve name
4 stages in face processing
structural encodoing
face recognition
person identification
name generation
face inversion effect for damaged brains
yin 1970
face inversion effect for damaged brains
explain
when shown upright faces-rh damaged patients perform worse than lh and control
rh damage may disrupt configural processing
when shown inverted faces-lh damage patients perform worse suggesting damage interrupts featural processing
people with prosopagnosia cannot demonstrate face inversion effect as they cannot apply configural processing and this cannot applied when the face us upside down
inversion superiority effect
gelder et al 1998
gelder et al 1998
inversion superiority effect
inversion superiority effect
explain
in inverted faces, people with prosopagnosia can process featural information without interference from disrupted configural system meaning that they have improved performance for the face inversion effect
so, are faces special?
yes
can recognise faces from birth
configural and featural
conditions
face/object dissociation
so, are faces special?
no
high exposure to faces
faces are stimuli we have got good at
visual expertise hypothesis
what is the visual expertise hypothesis
gauther and tarr 2002
face-selective mechanisms are also involved in recognising members of any category for which we possess expertise
