face recognition. name these famous faces cohen (1989) distinguishes between a) face identification:...

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  • Face Recognition

  • Name these famous faces

  • Cohen (1989) distinguishes betweena) Face identification: looking at a persons 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 RecognitionThere are two theories of face recognition you need to know for the exam.

    Feature Analysis

    Holistic Form Theory

  • Feature AnalysisThis is bottom up processingFeature are built up to form the face

  • Feature Analysis

    Visual cues are most important for recognition

    Separate features are analysed closely

  • 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.

    ConclusionWith 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 AnalysisDavis et al (1978). People had difficulty making photofit likenesses of faces even when the face was in front of themAlso when new people were asked to recognise the face from the photofit produced there success was just above chance levels

  • Holistic-forms TheoryThis is a top down processing approach.

  • Holistic-forms TheoryThe 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 TheoryEllis (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 Evidencea) 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.