Wednesday, May 6, 2020

Describe and evaluate Bruce and Youngs model of face recognition free essay sample

Describe and evaluate Bruce and Youngs model of face recognition (8+16marks) Bruce young’s model of face recognition starts with structural encoding, where the face is seen and the features are analysed. The model then splits up into separate compartments one for familiar faces and the other for unfamiliar faces. [AO1] The first of these compartments is the name generation system, which consists of eight separate processes. The first stage being the structural encoding where the face perceived is converted in neural impulses for the brain to interpret. [AO1] Followed by Face Recognition Units (FRU’s) where the brain contains stored structural descriptions of familiar faces, followed by the Person Identity Nodes (PINs) where stored information about the known individual’s e. g. their occupation, interests etc. Finally the name is generated; this is stored separately to the other information that is held of the person. [AO1] Bruce and Young believed that the serial nature of this meant that the model only goes in this order e. g. you can’t retrieve the person’s name without knowing personal information about them, however they do believe that you don’t necessarily go through all the stages and can stop at any if the information isn’t sufficient. [AO1] This compartment of the Bruce-young model can explain everyday face recognition problems very well, such as our failure to recognise a familiar face by giving a reasonable explanation of that there is sufficient-stimulation of an FRU for the face to be recognised. [AO2] It goes onto explain the reason why we mis-identify one person for another is because the person being identifies is sufficiently similar to the familiar person and therefore activates an FRU inappropriately. [AO2] Not being able to place a person is effectively explained by the relevant FRU not being activated enough due to the stimulation not being sufficient enough to activate the cognitive system or the PINs and so the information cannot be retrieved. [AO2]And finally it also successfully explains why we are sometimes not able to remember names, which is because of a problem occurring between the PINs and the name generation. [AO2] This model of face recognition also has much support from research studies, particularly those involving the use of brain damaged patients (For example; Young et al. , 1983) who asked 22 people to keep diaries of their everyday errors in person recognition. [AO2] A total of 1,008 errors were recorded and almost 20% of these referred to instances when someone knew alot of information about the person but could not think of their name. In contrast, no diarist reported being able to name a face whilst knowing nothing else about that person. This supports the idea that naming is a separate process. [AO2] Similarly, people often reported a feeling of familiarity but an inability to think of any personal details about the person. This suggests that the face recognition unit has been activated but not the PINs. [AO2] There is also support for the model from case studies of people with brain damage. The PET scanning to view areas of activity in the brain whilst different tasks are performed, has shown that different areas of the model are being accessed (Sergent Signoret, 1992)[AO2] A further study that supports this theory is by Young who asked nurses to keep a diary over an 8 week period about recognising faces. They found the most common problem experienced was remembering information about the person but not their name. This supports the serial nature of Bruce and Young’s model. [AO2] However it could be said that this study is mildly retrospective as the participants wouldn’t fill the diaries in until the end of the day so they might have forgotten what had happened during the day or might have forgotten to fill it in. [AO2] The second compartment are called parallel processes, these processes are able to occur separately of one another. These are able to occur without knowing the person (unfamiliar faces). [AO1] It is believed that after the structural encoding the information is passed to the facial expression analysis where the individual’s expression and speech is analysed e. g. their lip movement. Expression analysis helps us to recognise the angry person in a crowd, etc. [AO1] Like facial-speech analysis and directed visual processing, this relates more to the recognition of unfamiliar faces. After this it is passed to a node that notes other important information e. g. scars. All of these nodes for familiar and unfamiliar are linked to the Cognitive System. [AO1] The model has also been criticised as being descriptive rather than explanatory. It does not for example; explain how expression analysis is initiated, or how we are able to label certain emotions as â€Å"happy â€Å"or â€Å"sad†. [AO2] Although aspects of the model have been well supported by research, some of the components have been less well explained than others components are not all explained fully. This is particularly true of the cognitive system which was included in the model to explain processing not accounted for by the other components. It seems to link in with PINs, what we do know that it is holds additional information. [AO2] Furthermore, it focuses on how we recognize familiar faces, but not it is not much use for explaining how we can recognize a face that we have not seen before but are familiar, we can assume again that this may be due to us again having similar FRUs for the individual, but this is not explicitly explained. [AO2] Additionally, it fails to tell us how we learn to recognize and store new faces. Nor, does the model tell us anything about whether face recognition is a special perceptual process that is qualitatively different from other types of object recognition. [AO2] This model focuses mainly on the recognition of familiar faces and is of limited value in helping to understand how, for example, eye witness identification of unfamiliar faces can be improved. It also does not account for the processes involved in learning to recognize new faces and storing these images in memory. [AO2] The model has been criticised as being deterministic, in that it is a linear model. This suggests that face recognition can only occur in the order stated. It is possible that this occurs in many different ways, so it is invalid to state that it can only occur in one order.

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