The anatomical basis of face recognition: evidence from studies of intact individuals:

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The anatomical basis of face recognition
evidence from studies of intact individuals
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What is the anatomical basis of face recognition
in humans? Right hemisphere seems particularly
important for face-recognition. Farah (1990)
65 of 81 prosopagnosics had bilateral damage,
29 RH only, 6 LH only. RH important for
configural processing, LH for featural?
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Which hemisphere is most important for face
recognition? Divided-field studies with normal
people (Bourne, Vladeanu and Hole, 2008) Stimuli
in extreme left visual field go first to right
hemisphere, and vice versa. Both hemispheres can
recognise faces. LH featural processing. RH
configural processing.
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RH faster than LH with complete faces. Blurring
affects LH more than RH. Features-only affects
RH more than LH.
Mean RT ( 1 SE) to normal and blurred faces as a
function of visual field of presentation.
Mean RT ( 1 SE) to complete faces and the eyes
only as a function of visual field of
presentation.
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Bourne and Hole (2003) hemispheric differences
in processing incomplete faces
Complete
Eyes missing
Nose missing
Mouth missing
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Bourne and Hole (2003) hemispheric differences
in processing incomplete faces
Bars represent the difference between the
complete face condition and each experimental
condition. The greater the difference the more
detrimental the effect of the manipulation.
LH (featural) copes worse with missing features
than RH (configural).
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Tong, Nakayama, Moskowitz, Weinrib and Kanwisher
(2000)
fMRI study of fusiform responses to face-like
stimuli, eyes, houses and non-face objects. FFA
response similar for cat, cartoon and human faces
(with/without eyes) weaker for schematic faces
and eyes alone equal for front and profile
views, but declining as face rotated away from
view weakest for non-face objects and
houses. Conclusion fusiform gyrus responds best
to facial configurations plus features - involved
in "face" perception/detection.
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Schiltz, Dricot, Goebel and Rossion (2010)
fMRI adaptation study of neural responses to
composite faces. Right middle fusiform ("FFA")
sensitive to composites - treats them as "new"
faces. Right FFA involved in "holistic"
processing.
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Lee, Anaki, Grady and Moscovitch (2012)
fMRI study of responses to face halves
separated in time or space.
Behavioural data ISI 0 and ISI 200 similar ISI
800 and Misaligned similar to each other, and
worse than ISI 0 and ISI 200. ISI 800 activated
face processing regions (more bilaterally) plus
areas involved in attention and working memory
(strategic processing?) ISI 0 and ISI 200 better
identification correlated with increased activity
in configural processing network (R fusiform,
middle occipital, bilateral superior temporal,
inferior/middle cingulate and frontal
cortex). ISI 800 and Misaligned better
identification correlated with less activity in
these regions. Suggest configural and analytic
processing regions oppose each other.
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Nakayama et al (2000) PET study
Four visual tasks (a) Personally-familiar face
recognition. (b) Unfamiliar-face direction
discrimination. (c) Dot location on scrambled
face. (d) Familiar/unfamiliar scene
recognition. Bilateral occipital cortex and
posterior fusiform gyri respond to faces,
scrambled faces and scenes involved in
extraction of physical features from complex
images. Right inferior temporal/fusiform gyrus
responds selectively to faces (face
perception). Bilateral parahippocampal gyri and
parieto-occipital junctions respond selectively
to scenes. Right temporal pole is activated
during familiar/unfamiliar face and scene
discrimination probably involved in recognition
of familiar objects (memory in general).
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Gorno-Tempini and Price (2001) PET/MRI study
Four visual tasks (a) Famous face matching. (b)
Non-famous face matching. (c) Famous building
matching. (d) Non-famous building
matching. Category-specific perceptual
processing Faces (famous and non-famous)
activate fusiform gyrus. Buildings (famous and
non-famous) activate parahippocampal
gyrus. Shared analysis of semantic
processing Fame (faces or buildings) activates
left anterior middle temporal gyrus.
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Anatomical location of processes involved in face
recognition (Schweinberger and Burton (2003)
Fusiform gyrus Lingual gyrus Parahippocampal gyrus
Structural encoding N170 (superior temporal
sulcus)
Face recognition (Fusiform gyrus) N250R
PIN N400 (Anterior temporal lobe)
Name (Left temporal lobe)
Arousal to familiar face (Amygdala)
Skin conductance response
Semantic information (Anterior medial temporal
lobe)
Attribution processes
Integrative device
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Event-related Potential (ERP) studies of face
processing (Schweinberger 2003)
N170 Generated from posterior lateral
occipitotemporal cortex (superior temporal
sulcus). Larger for faces than most other visual
stimuli. Not human face-specific also produced
by car "faces", ape faces, schematic faces and
inverted faces. Unaffected by face familiarity or
face priming. i.e., not related to face
recognition. Correlate of structural encoding,
identification of face-like configurations?
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N250R Strongly right hemisphere. Affected by
familiarity of faces, and larger for
personally-familiar faces than famous faces.
Activity modulated in response to repeated faces
(even if diffferent views each time, though
strongest with identical images). Probably
generated from fusiform gyrus. Most response from
human faces then ape faces no response to
inverted faces or car "faces". Correlate of "face
recognition units"? N400 Anterior medial
temporal cortex. Correlate of "person identity
nodes" (post-perceptual response to individuals)?
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Barbeau, Taylor, Regis, Marquis, Chauvel and
Liegeois-Chauvel (2008) Intra-cranial ERP study
of time-course of famous face recognition. Massive
ly distributed processing from 110 -600 msec
post-stimulus - at least seven structures
involved.
Processing is not "one-way" - frontal areas
influence "earlier" stages. FG - invariant
aspects of faces STS - changeable
aspects. Perirhinal cortex -signals
"familarity". Temporal structures - recognition.
(Dark blue periods when recognition effects
were found).
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Outstanding questions How do the hemispheres
cooperate during normal face processing? Are the
RH and LH really specialised for configural and
featural processing, or are these merely
reflections of generalised differences in
processing modes? (RH global, LH local). In
particular, is featural processing really a mode
of face processing, or merely a strategy to cope
with odd-looking faces in psychology experiments?