Face Face RecognitionRecognition

Name these famous faces

Cohen (1989) distinguishes between

• a) Face identification: looking at a person’s face and knowing who it is.

• b) Face recognition: recognising the face as one we have seen before.

• c) Face recall: verbally describing a face from memory

Explanations for Face Recognition

• There are two theories of face recognition you need to know for the exam.

• Feature Analysis

• Holistic – Form Theory

Feature Analysis

• This is bottom up processingFeature are built up to form the face

FeatureFeature AnalysisAnalysis

Visual cues are Visual cues are most most important for important for recognitionrecognition

Separate Separate features are features are analysed analysed closelyclosely

Describe one of these faces to your partner and see if they can guess who it is from your

description; you can only use facial features to describe the face not hair or clothing

Evidence for Feature Analysis

Shepherd et al (1981) Aim.

To see what features were used in face recognition.

Method. People were briefly shown faces they had never see before and then asked to describe the from memory.

• Results

The features most often referred to were hair, eyes, nose, mouth, eyebrows, chin and forehead.

• Conclusion

With unfamiliar faces people used the main features of the face in order to recall it.

Ellis et al (1979)

With unfamiliar faces we tend to focus on external features when describing them(these can easily be altered eg hair dyed or cut)

With familiar faces we focus on internal features

Criticisms of Feature AnalysisCriticisms of Feature Analysis

1) Davis et al (1978). People had difficulty making photofit likenesses of faces even when the face was in front of them

2) Also when new people were asked to recognise the face from the photofit produced there success was just above chance levels

Holistic-forms Theory

• This is a top down processing approach.

Holistic-forms Theory

• The face is recognised as a whole.

a) by analysing the relationship between the various facial features.

b) by feelings aroused by the face

c) by semantic information about the person

Holistic-forms Theory• Ellis (1975) says we

have a stored templates of faces we know.

• When we see a face we try to match it to one of our stored mental templates of faces

The holistic form of these faces has been altered; can you recognise them

It is easier when the holistic form of the face is intact

Evidence Young and Hay (1986)

• Aim: To see if the configuration of a face was important for recognition

• Method. Pictures of famous faces were cut in half horizontally.

People were asked to say who the half face was a)) when they just saw each separate half face.

b) when the half faces were combined with a none matching opposite half face

Evidence Young and Hay (1986) Results. People took longer to recognise the half

faces when they were combined in none matching pairs.

This was because when put together the none matching half faces produced a new holistic form

Conclusion. The configuration of the face is important for face recognition

Other Supporting Evidence

• a) Haig (1984) – Recognition time increased for famous faces when the spacing between features were altered

• b) Yin (1989) - Recognition of faces took longer when the face was shown upside down

A criticism of Holistic-Forms Theory is that it is not a good explanation of how we recognise unfamiliar faces.

In actual fact to some extent we probably use both methods. If a face had a particularly prominent feature we may use feature analysis, but for the most part holistic forms is used.