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O + E Bruce and Young’s theory of face perception

Is there a specific part of the brain for face perception?

If there is, how is it doing it?

A clear and detailed account of the model, fully evaluated and linked to AIDS

Give a full outline of the model and evaluations that are expanded on

Describe B&Y’s model limited to FRU, PIN and name generation. Provide some +/- evidence

Fusiform Gyrus

What evidence is there that there is a specific part of the brain for face processing?

If this is true, how did we first discover it?

Who would help us prove it initially?

Why might it be useful?

NOT special for faces!

• Is it special processing for FACES, or just differentiating between similar looking ‘objects’?

• Gauther et al (2000)• Used fMRI to look at peoples brains as

they were asked to identify types of birds, and types of cars (when shown a picture of them)

What type of Bird is this?

Gauthier et al (2000)

• The fusiform Gyrus is also active during this task, so it might not be exclusively for face recognition.

• Particularly true if they are experts in that field e.g. birdwatchers.

• Conclusion- The fusiform area is specialised for ‘expert’ processing (we are all experts with faces, particularly those of our own race).

…….If they are right

I am a Birdwatcher!

Doing a face recognition task…….

…..and a bird recognition task

Arrggghh!!

They compete for the same area of the brain and it is difficult!

Feature analysis and holistic processing

• Shepherd, Davies and Ellis (1981)

• Showed P’s unfamiliar faces and asked them to describe them….

What did she look like?

Features are IMPORTANT

• But just because that is how you describe them, doesn’t mean that is how you perceive them

• It is really hard to recognise faces if you ONLY see the features, so maybe we process the whole face

• This is called Holistic processing

Bruce and Valentine (1986): scrambled faces are harder to process

Not hard for objects, why for faces?

Yin (1969) Inversion Effect

• Objects are easy to recognise upside down, but faces are hard.

• Yin suggests this is because inversion interferes with holistic processing but not feature processing.

• Therefore- faces are processed ________

Bruce & Young’s model of face recognition (1986)

Errors in face recognition (Young, 1986)

• Failure to recognise a familiar person (e.g. if they had grown a beard)

• Mistakenly identifying one person as another (typically in poor viewing conditions)

• Recognising a person but being unable to place them or remember their names

• Inability to remember someone’s name, even when other personal details were recalled

Don’t write these down!

Young et al. (1986)

• CONCLUSION: there are at least THREE separate systems involved in face recognition:– A face recognition system– A semantic system that includes general

information about people (job, etc.)– A name system

http://www.resourcd.com/@psychexchange/video/show/1182

View-centred descriptions

Expression-independent descriptions

Structural Encoding

WE LOOK AT A FACE:

Information is first encoded: this information is expression INDEPENDENT, first because we recognise faces irrespective of their expression and second because there is clinical evidence that we process faces and emotional expressions separately. Some patients can recognise faces and not emotions and vice-versa.

Structural Encoding

Face Recognition Units (FRUs)

This structural encoding stimulates the FACE RECOGNITION UNITS. The closer the correspondence between the face that is seen and the information that is stored in a FRU, the stronger the activation will be.

Structural Encoding

Cognitive System

Person Identity Nodes (PINs)

The FRUs are linked to both the cognitive system and to person identity nodes (PINs). Face recognition makes available other information about the person from which identification can be made, such as their job or hobbies. Information from the cognitive system is included because we may often recognise someone using information other than their face, such as their voice or the way they walk.

Structural Encoding

Cognitive System

Name Generation

The PIN is the point at which recognising a person can be said to have taken place. After this, name generation can occur! This is the process most likely used whenever we are identifying a person with whom we are familiar.

The Directed Visual Processing Unit is included because we can choose to focus on certain aspects of a face – e.g. if we are meeting a friend in a crowded space we may choose to look for someone with a particular hair colour.

Structural Encoding

Cognitive System

Directed visual

processing

Name Generation

The Facial Speech Analysis unit is included because there is clinical evidence that lip reading is a separate ability from face recognition: some patients with brain damage can read lips but not recognise faces, and vice-versa.

Structural Encoding

Cognitive System

Directed visual

processing

Facial Speech Analysis

Name Generation

Structural Encoding

Cognitive System

Directed visual

processing

Facial Speech Analysis

Expression Analysis

Name Generation

Expression analysis helps us to recognise the angry person in a crowd, etc. Like facial-speech analysis and directed visual processing, this relates more to the recognition of unfamiliar faces.

Using the model

• Failure to recognise a familiar face:– There is insufficient stimulation of a FRU for the face to be

recognised.

• Misidentifying one person for another:– The person misidentified is sufficiently similar to the familiar

person to activate a FRU inappropriately.

• Not being able to place a person:– The relevant FRU has been activated but the stimulation was not

sufficient to activate the Cognitive System or the PIN and so retrieve more information.

• Not being able to remember a name:– A problem has occurred between the PIN and Name Generation

system.

Evaluation of the model

• The model can predict and explain many research findings particularly relating to brain-damaged patients.

• It can account for the recognition errors reported by Young et al.’s (1986) research. E.g. almost 20% of P’s referred to instances where they knew a lot of information about a person but couldn’t think of their name, however no-one reported being able to name a face whilst knowing nothing else about the person.

Inverted faces:

The two faces look similar when upside down, but when turned the right way up one suddenly looks very different from the other. This shows that features on the face are processed separately (if whole faces were processed then the two images would instantly be seen as different to each other). It also shows that the second stage, where facial features are combined to get a mental image of the whole face, only works when everything is the right way up, as this is how we normally see faces.

Who is this? the Thatcher illusion (Johnson,1980)

Evaluating Bruce and Young (1986)Evaluating Bruce and Young (1986)

Ellis et al (1979) found that external facial features, like hairstyles, are used to recognise unknown faces, while internal features (like noses) are used with familiar faces.

Malone et al (1982) reported two case studies;• a man able to recognise familiar faces but who could not match photos of unknown faces.• a man who could not recognise familiar faces but could match photos of unknown people.The results point to damage to different areas of the brain.

Young et al (1985) asked 22 participants to keep a record of the mistakes they made when recognising people. They found that many errors involved recalling information about a person but not recalling their name, but never recalling a name without some relevant personal information.

Evaluating Bruce and Young Evaluating Bruce and Young (1986)(1986)

Young et al (1986) found that participants were faster at identifying whether a particular face was that of a politician than they were at identifying the politician’s name.

Stanhope and Cohen (1993) found that participants could recall the names for faces, despite having no information about personal identity (PINs)

Evaluating Bruce and Young Evaluating Bruce and Young (1986)(1986)

• The main strength is that the model generates precise predictions that can be tested.

• Clear differences in the way familiar and unfamiliar faces are recognised.

• However, the details of unfamiliar face processing are vague and other components of the model (such as the cognitive system) are not clearly explained.

Evaluation of the model (cont)

• Some of the components have been less well explained than others. The role of the cognitive system is unclear.

• The model focuses on the recognition of familiar faces and is of limited value in helping to understand how, for example, eyewitness identification of unfamiliar faces can be improved.

• It does not account for the processes involved in learning to recognise new faces and storing these images in memory.

• The model is neutral on the question of whether face recognition is a special perceptual process that is qualitatively different from other types of object recognition. Evidence from brain-damaged patients is more revealing in relation to this!

Bruce and Young’s Theory

Bruce and Young (1986)

Stages of face recognition– 1. Structural encoding – 2. Expression analysis– 3. Facial speech analysis – 4. Directed visual processing – 5. Face recognition nodes– 6. Person identity nodes– 7. Name generation – 8. Cognitive system

Bruce and Young’s (1986) Model of Face Recognition

Researching Face Recognition

• Bruce and young model would suggest participant recall for face and name condition (set 2) would be poorer than the recall from set .

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