Cognitive Development of Face Processing
Models of Face Recognition
Bruce and Young Model (1986):
Recognition is facilitated by the development of Person Identity Nodes (PINs), which are composed of Face Recognition Units (FRUs).
Identification of Familiar Faces:
Achieved through the activation of stable “average” representations (Valentine, 1991).
Cortical Basis of Face Recognition
Face Fusiform Area (FFA):
A brain area activated more by faces than other visual objects.
Lesioning this area induces Prosopagnosia (face blindness).
Prosopagnosia:
An inability to recognize other humans by their faces.
Distributed Neural System for Face Processing
Models Summary
Face processing involves a distributed network of regions.
Similarities amongst other species suggest an evolved network.
Early Face Processing System
Preference for face schema at birth (Johnson & Morton, 1991; Valenza et al., 1996).
Face Detection
Selective Attention: Are faces selectively attended to (i.e., prioritized) above other stimuli?
Di Giorgio, Turati, Altoe & Simion (2012) found that adults and 6-month-olds (n=12), but not 3-month-olds (n=19), detected faces in heterogeneous displays.
Visual Array Approach:
Detection found for color images (e.g., Gluckman & Johnson) but only in 2-item arrays for 4-month-old infants and when competing stimulus has low physical salience (Kwon et al., 2016).
Grid Displays: Faces are also found efficiently in grid displays (Jakobsen et al., 2016).
*Recent work by Simpson and colleagues has also shown support for rapid and early face detection using arrays and grids.Adults are also faster to detect human faces relative to non-human primate faces and animal faces.
More Naturalistic Testing:
Requires computation.
Assess visual properties of images using saliency analysis.
Potential Outcomes:
Detected.
Found.
Missed.
Findings:
Performance is better in more complex tasks (500 msecs versus 2 secs in Simpsons et al. 2019).
Adult-like saccadic responses observed.
Social information affects eye movement behavior.
Faces fixated differently to ‘other’ locations.
Two-Process Theory of Face Processing
Suggests that we have a subcortical (CONSPEC) and a cortical system (CONLERN).
The subcortical system detects faces and guides visual attention towards relevant stimuli. This encourages the development of the cortical system.
Originally considered that subcortical system declined around 1 month after birth (Morton & Johnson, 1991)
Now acknowledged that face detection continues into adulthood (Johnson et al., 2015).
Eye Contact:
The two-process theory suggests that eye contact might be critical for face detection (Johnson et al. 2015).
Detection was superior when faces had eye contact, but again they used visual arrays.
Findings from Kelly et al. (2019) suggest that eye contact is not necessary.
Might be a question of stimuli and methods
Face Processing in Infancy
Early in life infants are able to recognize individual primate faces (Pascalis, de Haan, & Nelson, 2002).
This ability declines between 6-9 months of age unless artificial exposure is provided (Pascalis et al. 2005).
Visual Preference
Kelly et al. (2005) tested preference for faces of different races in neonates and 3-month-old infants.
Newborn infants do not look preferentially at own- or other-race faces
Three-month-old infants look preferentially at own- race faces when paired with other-race faces.
Own-race preference also reported in Israeli and Ethiopian infants
Ethiopian infants raised in an absorption centre exposed to Caucasian and African faces showed no preference.
Conclusions:
Newborn infants are able to perceive differences between racial categories, but the differences are meaningless to them.
Predominant exposure to own-race faces produces preferential looking by 3 -months of age
Early face preferences are shaped by the environment.
Perceptual Narrowing
Phoneme discrimination and face preferences becomes 'tuned' by environment - sensory inputs.
Kelly et al. (2007; 2009) tested OR face recognition in 3-, 6 - and 9-month-old infants Caucasian, Chinese, Middle Eastern and African faces.
Infant Face Recognition
Preference for mother’s face at 3 days of age (Bushnell et al., 1989; Pascalis et al., 1995).
Recognition of a picture of a face learned 2 minutes before in 4-day-olds (Pascalis and de Schonen, 1994).
3- and 6-month-olds recognize human faces presented on different point of view (Pascalis et al., 1998).
Infants’ ability to process different aspect of faces is well developed during the first year of life.
What is the function of narrowing?
It is not certain, but probable that narrowing help us to become efficient at processing the types of information most frequently encountered
Reflects the interaction between immature cognitive systems and early experience
The extent to which narrowing can be reversed is still debated, but it is clear that some plasticity remains (e.g., Heron-Delany et al., 2011; Pascalis et al., 2005).
Underlying mechanisms are uncertain, but the process of narrowing is an important path to perceptual specialisation and expertise.
Head-Camera Studies
What do infants see in their day-to-day lives?
One- and three-month old infants wore pinhole cameras
Worn whenever the infant was awake
Exposure to faces was coded
Findings:
Around 25% of all footage contained faces in the infant’s environment
Each face was in view for 4s on average
More female faces were viewed
More own-race faces were viewed
Why Eye Movements?
Oculomotor system is mature by 2 months of age
Infant saccades may even be faster than adult saccades
More reliable than motor responses
Landing position accuracy of saccades is not yet clear, but available data suggests they are reliable (e.g., Kelly et al., 2019)
Adult-like fixation behaviour is observed by 12 months of age (Helo et al., 2016)
Shorter fixations during initial viewing (1.5 s), then longer
Face Processing - Summary
A specialized face processing system is observed in non-human primates (and other species)
The face system would have kept comparable abilities throughout evolution
It is then possible that a good part of the face system development is genetically determined
The environment will finalize the specialisation of the face system
What happens if we are deprived at an early age of such information?
Early Visual Deprivation
Adult levels of face recognition take years to develop (e.g., Carey & Diamond, 1994)
Adults show sensitivity to spatial configuration of facial features – configural processing
Le Grand et al. (2001) found that deprivation of patterned visual information in early infancy left permanent deficits in configural processing
Tested adolescents born with cataracts that were removed between 2-6 months of age
At time of test, all patients had a minimum of nine years visual experience
Cataract patient’s performance was significantly poorer than aged matched-controls and adults
Mondloch, Lewis, Levin & Maurer (2013) tested infants with cataracts removed within first weeks of life
Used a face detection task within one hour of their first focused visual input
Like newborns, but unlike age matched controls, infants showed a preference for face-like stimuli ( config) over an inverted counterpart
Conclusion
A specialized face processing system is observed in non- human primates (and other species)
The face system would have kept comparable abilities throughout evolution
It is possible that a substantial part of the face system development is genetically determined
*The environment will finalize the specialisation of the face system
Okay, I have reworded the previous summary to be more detailed and easier to understand. I've also expanded the study explanations and provided guidance on how to approach the university-level essay questions.
Detailed Summary of Face Recognition
Core Concept: Our brains have a specialized system dedicated to recognizing faces. This system starts developing very early in life and continues to be refined by our experiences.
Brain Areas Involved: The Face Fusiform Area (FFA) is a key region in the brain that is more active when we look at faces compared to other objects. Damage to this area can lead to prosopagnosia, also known as face blindness.
Early Development: Infants show preferences for face-like patterns very early. Over time, their ability to recognize faces becomes more tuned to the faces they see most often in their environment. This is known as perceptual narrowing.
Environmental Influence: The faces we are exposed to early in life shape our ability to recognize faces. For example, infants show a preference for faces of their own race by 3 months of age, reflecting their visual environment.
Impact of Experience: Studies on infants with cataracts (clouding of the lens) have shown that early visual experience is crucial for developing normal face processing abilities.
Detailed Study Explanations
Bruce and Young Model (1986):
Main Idea: This model proposes that face recognition involves specific units in the brain.
Person Identity Nodes (PINs): These nodes contain information about a person's identity.
Face Recognition Units (FRUs): These units store visual information about faces.
How it Works: When you see a face, the FRUs activate, which then activate the corresponding PINs, allowing you to recognize the person.
Di Giorgio, Turati, Altoe & Simion (2012):
Main Idea: This study investigated when infants start to selectively attend to faces.
Method: Researchers presented infants with displays containing various stimuli, including faces.
Findings: They found that adults and 6-month-olds could detect faces in the displays, but 3-month-olds could not.
Implication: This suggests that the ability to selectively attend to faces develops between 3 and 6 months of age.
Kelly et al. (2005):
Main Idea: This study examined the development of racial biases in face preference.
Method: Researchers presented newborns and 3-month-old infants with pairs of faces, including faces of their own race and faces of other races.
Findings: Newborns showed no preference, but 3-month-olds preferred faces of their own race.
Implication: This suggests that early exposure to faces of a particular race leads to a preference for those faces.
Kelly et al. (2007; 2009):
Main Idea: This series of studies explored perceptual narrowing in face recognition.
Method: Researchers tested 3-, 6-, and 9-month-old infants on their ability to recognize faces of different races.
Findings: They found that infants became better at recognizing faces of their own race but worse at recognizing faces of other races as they got older.
Implication: This demonstrates that face recognition becomes tuned to the faces most frequently encountered in the environment.
Head-Camera Studies:
Main Idea: These studies aimed to understand the visual input that infants receive in their daily lives.
Method: Researchers fitted infants with head-mounted cameras to record their visual experiences.
Findings: They found that faces were present in about 25% of the footage, and infants tended to view more female and own-race faces.
Implication: This provides insight into the types of faces that infants are exposed to, which can influence their face recognition abilities.
Le Grand et al. (2001):
Main Idea: This study investigated the impact of early visual deprivation on face processing.
Method: Researchers tested adolescents who had cataracts removed in infancy on their ability to process faces.
Findings: They found that these individuals had deficits in configural processing, which is the ability to process the spatial relationships between facial features.
Implication: This suggests that early visual experience is crucial for developing normal face processing abilities.
Mondloch, Lewis, Levin & Maurer (2013):
Main Idea: This study examined face preference shortly after visual input.
Method: Researchers tested infants shortly after cataract removal
Findings: They found that these individuals had preference for face-like stimuli.
Implication: This suggests that early visual experience is crucial for developing normal face processing abilities.
University-Level Essay Questions (with guidance on how to answer)
Discuss the role of nature vs. nurture in the development of face recognition abilities. How do studies of infants with cataracts contribute to this debate?
How to Approach:
Define "nature" (genetics) and "nurture" (environment).
Discuss how some aspects of face processing appear to be innate (e.g., preference for face-like stimuli in newborns).
Explain how environmental factors, such as exposure to faces of a particular race, shape face preferences and recognition abilities.
Integrate findings from studies of infants with cataracts to highlight the critical role of early visual experience.
Explain the concept of perceptual narrowing in face recognition. What are the potential benefits and drawbacks of this process?
How to Approach:
Define perceptual narrowing as the process by which the brain becomes more specialized for processing information that is frequently encountered.
Describe how perceptual narrowing affects face recognition, leading to improved recognition of familiar faces but decreased recognition of unfamiliar faces.
Discuss potential benefits, such as increased efficiency in processing relevant information.
Discuss potential drawbacks, such as difficulty recognizing individuals from different racial or ethnic groups.
Critically evaluate the methodologies used to study face recognition in infants. What are the strengths and limitations of these approaches?
How to Approach:
Discuss various methodologies, such as preferential looking paradigms, habituation techniques, and head-mounted cameras.
Analyze the strengths of each approach, such as the ability to assess face preferences in preverbal infants.
Discuss the limitations, such as the potential for confounding factors (e.g., stimulus salience) and the difficulty of generalizing findings from artificial laboratory settings to real-world situations.
How do the findings from head-camera studies enhance our understanding of infant face processing?
How to Approach:
Describe the head-camera study methodology.
Explain that the primary finding is that infants spend the majority of their time looking at female and own-race faces.
Discuss the importance of the face processing system developing from facial input, and that early biases such as these are a key element of developing the face processing system.