The general purpose of this thesis was to investigate face recognition for persons with or without learning disability. Three specific research questions were investigated:
1. How does familiarity of faces interact with familiarity of environments in pictures for persons with learning disability?
2. Which, if any, of the 2 theoretical approaches to memory conjunction errors, the binding approach and the dual-processing approach, can explain performance for both persons with and without learning disability?
3. How does working memory relate to performance in memory conjunction error studies?
The results of the 4 papers included in this thesis provided answers to the questions:
1. A person by environment interaction was found and was explained by an absent, present or implausible association between the person and the environment in the picture. These semantic relations determined performance and a “lazy” semantic strategy was suggested.
2. Different group by recognition type interaction patterns, and specifically different amounts of conjunction errors, were found for different degrees of task difficulty. These patterns could neither be explained by the dual processing approach nor the binding approach. Hence, a new frame of interpretation which included working memory was suggested.
3. High working memory capacity was associated with 2 effects: firstly, recognition of more facial features and, secondly, recognition of more facial configurations. At high working memory demands, participants relied on the first effect to a higher degree, at the expense of the other.
It was also found that, in a task with low working memory demands, the performance for persons with learning disability was similar to the performance of age-matched controls with higher working memory demands in the task. This indicates that learning disability, at least in this type of recognition task, can be “simulated” by higher working memory demands in a population without learning disability. This finding is discussed in relation to witness psychology and the use of photographs as cognitive assistance.