Memory conjunction errors, that is, when a combination of 2 previously presented stimuli is erroneously recognized as previously having been seen, were investigated in a face recognition task with drawings and photographs in 23 individuals with learning disability, and 18 chronologically age-matched controls without learning disability.Compared to the controls, individuals with learning disability committed significantly more conjunction errors, feature errors (1 old and 1 new component), but had lower correct recognition, when the results were adjusted for different guessing levels. A dual-processing approach gained more support than a binding approach. However, neither of the approaches could explain all of the results. The results of the learning disability group were only partly related to nonverbal intelligence.
Keywords: Face recognition, memory conjunction errors, learning disability
Author noteThis research was financed by the Swedish Defence Research Agency. We thank pupils, teachers, and other personnel at the participating school for their collaboration.We also thank Neal Kroll and Mark Reinitz for making the picture material used in their studies available to us. Correspondence concerning this article should be addressed to Henrik Danielsson, Department of Behavioural Sciences (IBV), Linköping University, SE-581 83 Linköping, Sweden, or henda@ibv.liu.se.Telephone +46 13 28 21 99 and fax +46 13 28 21 45.
Memory Conjunction Errors and Learning Disability 3The Face You Recognize May Not Be the One You Saw:
Memory Conjunction Errors in Individuals With or Without Learning DisabilityMemory conjunction errors represent a form of memory illusion (see Roediger, 1996, for an overview) in which individuals erroneously recognize a stimulus as "old", though it is a combination of two previously presented stimuli. One example of a memory conjunction error is that subjects studying lists with compound words like "Heartache" and "Toothpaste" have a strong tendency to claim that test words like "Toothache" have been seen before . This effect has been shown for many different types of stimuli, for example, nonsense words (Reinitz, Lammers, & Cochran, 1992;Reinitz & Hannigan, 2001), real words (Reinitz, Verfaellie, & Milberg, 1996;Rubin, Van Petten, Glisky, & Newberg, 1999;Marsh, Hicks, & Davis, 2002Jones, Jacoby, & Gellis, 2001), sentences (Reinitz et al., 1992), colors (Zimmer & Steiner, 2003), environments with landmarks (Albert, Reinitz, Beusmans, & Gopal, 1999), autobiographical events , drawings of faces (Reinitz et al., 1992; Kroll, Knight, Metcalfe, Wolfe, and Tulving, 1996), and photographs of faces (Bartlett, Searcy, & Abdi, 2003;Busey & Tunnicliff, 1999). There have also been some studies of special populations, for example individuals with amnesia (Reinitz, Verfaellie, & Milberg, 1996), individuals with hippocampal damage (Kroll, Knight, Metcalfe, Wolf, & Tulving, 1996;Stark & Squire, 2003), and older adults (Rubin et al., 1999), but none with individuals with learning disability.The purpose of t...
