faces

F A C E P E R C E P T I O N D R V I C T O R I A W R I G H T / / P S 2 1 8 2 0 / / 2 0 2 5 - 2

T O D A Y ’ S S E S S I O N

  • Introduce a model of face processing that accounts for the recognition of familiar faces.

  • Discuss key findings from the face recognition literature and their implications on face processing.

  • Introduce prosopagnosia as a selective deficit in the processing of faces.

  • Consider the proposition that faces are a special class of stimuli.

T W O K E Y Q U E S T I O N S

  • Are faces special?

  • Is face processing configural or featural?

F A C E S I N C O G N I T I O N

  • Recognizing faces requires within-category discrimination and between-category discrimination.

  • Within-category discrimination: distinguishing between different faces within the same category.

  • Between-category discrimination: distinguishing between different categories of stimuli, which may not include faces.

F A C E S A S S O C I A L S T I M U L I

W H A T I N F O R M A T I O N D O W E G E T F R O M F A C E S?

  • Facial features provide crucial social information: emotions, identity, and intentions.

B R U C E & Y O U N G (1986)

Stages of Face Processing:

  1. Structural Encoding

    • Can you perceive that this is a face?

  2. Face Recognition

    • Do you know if the face is familiar?

  3. Person Identification

    • Do you know whose face it is?

  4. Name Generation

    • Do you know the name of this person?

Related Concepts in Face Processing:

  • Expression analysis, view-centered descriptions, facial expression-speech independent analysis, directed visual processing, face recognition units, cognitive system, person identity nodes.

K E Y Q U E S T I O N: C O N F I G U R A L V S . F E A T U R A L

  • Configural Processing: Whole, holistic detection of faces.

  • Featural Processing: Parts-oriented, piecemeal detection of facial components.

K E Y F I N D I N G S I N F A C E R E C O G N I T I O N

T H E D I S T I N C T I V E N E S S E F F E C T

  • Distinctive faces are recognised better than less distinctive faces (Bruce et al., 1994).

F A C E I N V E R S I O N E F F E C T (Yin, 1969)

  • Performance is always better for upright faces compared to inverted faces.

  • Inversion disrupts face processing more significantly than for other types of stimuli (e.g., houses, stick people).

  • Inversion primarily affects configural processing, but not featural processing.

W H O L E - O V E R - P A R T E F F E C T (Tanaka & Farah, 1993)

Study Phase:

  • Recognition tested by asking, "Which is Larry’s nose?"

Test Phase:

  • Participants demonstrated higher accuracy in recognizing features when they were embedded in a complete face.

  • Suggests that face processing is holistic (configural) rather than merely feature-based.

C H I M E R I C F A C E E F F E C T (Young, Hellawell & Hay, 1987)

  • Aligned halves of faces create a strong impression of a new face.

  • Recognition of individual ‘donors’ becomes difficult.

  • Upright faces prompt configural processing.

T H E T H A T C H E R E F F E C T (Thomson, 1980)

  • Subtle relational changes between features are harder to identify in inverted faces.

  • Demonstrates disruption of holistic/configural processing.

D O E S D I S T O R T I N G F A C E S A F F E C T R E C O G N I T I O N?

  • Hole et al. (2003): Studied effects of various transformations (vertical stretching, horizontal stretching, shearing, and inversion) on familiar face recognition.

K E Y F I N D I N G S I N F A C E R E C O G N I T I O N

  • Evidence from face inversion, chimeric faces, whole-over-part, and Thatcher effect suggests that configural (or holistic) processing plays a significant role in face recognition.

I S F A C E R E C O G N I T I O N I N N A T E?

  • Johnson et al. (1991): Newborns orient towards moving face-like stimuli more than scrambled face stimuli.

  • Turati et al. (2002): Infants preferred top-heavy configurations over symmetrical face configurations.

  • Simion et al. (2002): Infants fixate longer on patterns with more elements in the top half, suggesting innate preferences for face-like structures.

E F F E C T O F V I E W P O I N T C H A N G E S

  • In daily life, we rarely see the same face from the exact same angle or viewpoint.

  • Changes in viewpoint may alter the amount of information available for recognition and may make recognition more challenging.

E F F E C T O F V I E W P O I N T C H A N G E S (Stephan & Caine, 2007)

  • Participants trained on unfamiliar faces at three-quarter view.

  • Recognition tasks manipulating available information (eyes only, nose only, mouth only) and angle of rotation showed that performance was best with whole faces.

  • Deleting eye information had the most significant impact on recognition performance.

  • Accuracy reduced for profile view as critical information about the eyes is lost.

W H Y A R E W E S E N S I T I V E T O G A Z E D I R E C T I O N?

  • Gaze direction can indicate intent to initiate communication or prompt attention to an object.

  • Direct gaze may signal potential threats, tapping into survival mechanisms.

F A C E S A N D A S D

  • Autistic Spectrum Disorder (ASD) encompasses various neurodevelopmental conditions, primarily characterized by reduced social interaction and engagement in repetitive behaviors.

  • The Theory of Mind in ASD relates to the understanding of others' thoughts, beliefs, and emotions, with faces being vital for recognizing these mental states.

ASD & F A C E P R O C E S S I N G

  • Children with ASD show poorer performance in recognizing identity, emotional expression, gaze direction, and lip reading compared to controls (Deruelle et al., 2004).

  • ASD participants focus less on facial features and more on non-feature areas of the face (Pelphrey et al., 2002).

A S D & W H O L E - O V E R - P A R T A D V A N T A G E

  • Typically developing children show superior identification of facial features embedded in a face.

  • ASD children only demonstrated this advantage for mouth features, and they particularly struggled with eye stimuli, indicating flexible processing strategies (Joseph & Tanaka, 2003).

F A C E S A N D S O C I A L A N X I E T Y

  • Individuals with social anxiety often avoid social situations due to fear.

  • Garner et al. (2009): Participants with social anxiety found it challenging to recognize emotionally ambiguous faces compared to non-anxious controls.

F A C E S & S O C I A L A N X I E T Y (Horley et al., 2004)

  • Social anxiety participants exhibited longer scan paths, indicative of hyperscanning.

  • Tended not to fixate on the eye region, particularly for angry-faced stimuli.

P R O S O P A G N O S I A

  • Defined as the inability to recognize faces, which can be developmentally or acquired.

  • First described by Bodamer (1947) through the case of Patient S, who suffered from a brain injury, highlighting the complexity involved in face recognition.

P R O S O P A G N O S I A D I A G N O S I S

  • Corrow, Dalrymple & Barton (2016) addressed the diagnosis and implications associated with prosopagnosia.

C A S E S T U D I E S

  • Patient PG (Young et al., 1988): Damage to right hemisphere, inability to recognize familiar faces while structural encoding intact.

  • Patient PH (Dr Haan et al., 1987): Could identify faces but not recall semantic information.

  • Patient ME (De Haan et al., 1991): Perceived and encoded faces and could make familiarity decisions but had anomia (inability to retrieve names).

  • Patient EST (Flude et al., 1989): Similar patterns observed but some capacity to engage in basic processing was retained.

S T A G E S I N F A C E P R O C E S S I N G

Patient

Structural Encoding

Face Recognition

Person Identification

Name Generation

PG

û

û

û

û

PH

ü

û

û

û

ME

ü

ü

û

û

EST

ü

ü

ü

û

P R O S O P A G N O S I A & C O N F I G U R A L P R O C E S S I N G (Uttner et al., 2002)

  • Individuals with prosopagnosia might demonstrate a failure to integrate facial features into a whole.

  • Case studies indicate varied strategies used to identify faces; some may leverage distinguishing features such as eyebrows.

F A C E I N V E R S I O N E F F E C T: R E V I S I T E D (Yin, 1970)

  • Patients with left hemisphere damage performed poorly when shown inverted faces, indicating an interruption of featural processing.

  • Conversely, right hemisphere damage resulted in poorer performance on upright faces, suggesting disruption of configural processing.

A R E F A C E S S P E C I A L?

Cognitive Neuroscience Insights

ERP Studies:

  • N170 ERP component is larger in the right hemisphere (Bentin et al., 1996), suggesting specialized processing for faces by the right hemisphere.

Activation Patterns:

  • Fusiform gyri more activated by faces, varying according to orientation (upright vs. inverted).

F A C E S A R E N ’ T S P E C I A L!

  • Human beings are classified as face experts due to extensive exposure and experience with faces.

  • The Visual Expertise Hypothesis (Gauthier & Tarr, 2002): Proposes that mechanisms developed for face recognition also apply to other categories with a high level of expertise.

Studies Supporting Expertise:

  • Gauthier et al. (1999) trained participants on Greebles, resulting in increased performance and brain activity linked to object recognition with experience.

  • Expertise extends to cars and birds, indicating transferability of facial recognition skills across categories (Gauthier et al., 2000).

C O N C L U S I O N

  • Faces may be special in terms of innate recognition abilities and configural vs. featural processing aspects but not exclusively so.

  • High exposure results in the ability to apply visual expertise more broadly across different stimulus categories.

N O T E - T A K I N G A N D R E V I E W

  • Regular revision of these key themes and findings can enhance understanding of face perception and its implications in various social and clinical contexts.