It is recommended that researchers and practitioners consider individual differences in demographic, cognitive, personality, social, and emotional variables when evaluating the Cognitive Interview (CI) and that the mental imagery component of the CI be omitted.
2. Traditionally, research examining eyewitness memory and memory errors has not focused on individual differences (Hosch, 1994; Schooler & Loftus, 1993). However, some researchers have used the misinformation paradigm to investigate various demographic variables associated with suggestibility. Concerning age, such research reveals that, in response to free recall, young children remember less information in comparison to older children and rarely recall incorrect information. However, young children demonstrate more errors than older children when responding to unbiased and misleading cues and, under most conditions, demonstrate more susceptibility to suggestion (see Ceci & Bruck, 1993). Memon & Stevenage (1996) acknowledge age effects and recommend that the CI be used only for children over the age of 8. However, they failed to provide theoretical explanation for such developmental differences. Several researchers have used fuzzy-trace theory to explain some of these findings (Cassel & Bjorklund, 1995; Ceci & Bruck, 1993; Reyna, 1994).
3. Fuzzy-trace theory explains age effects by calling attention to young children's greater reliance on verbatim traces, which are less likely to be retrieved and more prone to forgetting and suggestibility in comparison to fuzzy, or gist-like, traces. Verbatim traces deteriorate rapidly and thus may be inaccessible when post-event information is provided or when suggestive questions are asked. Therefore, inaccurate information has an increased likelihood of incorporation with real memories and of becoming indistinguishable from them (Ceci & Bruck, 1993).
4. In other work examining demographic variables, Loftus, Levidow, and Duensing (1992) conducted an experiment that examined gender, educational level, and occupation in addition to age. Results indicated that children aged 5 to 10 years and senior citizens aged 65 and over were relatively inaccurate and suggestible. Loftus et al. (1992) also found that artists and architects were relatively accurate but highly suggestible. Loftus et al. (1992) suggested that differences in imagery ability may explain the latter effect and hypothesized that artists and architects may possess a greater ability to clearly imagine misleading suggestions and therefore, they may appear more real to them. Since mental imagery is one of the cognitive strategies used in the CI, it appears that individual differences in imagery ability warrant consideration.
5. The mental imagery component of the CI asks the witness to visualize scenes from the perspective of a person or an object located in another position in the room. Ceci & Bruck (1995) note that this technique enhances the risk that fantasies will be incorporated into children's beliefs, especially if the interviewer fails to provide a context for reality testing. Research examining adult source monitoring reveals that mentally imagining events produced memories of real events that were more similar to memories of imagined events (Suengas & Johnson, 1988).
6. Several researchers have examined individual differences in mental imagery. For example, Tousignant (1984), as cited in Schooler and Loftus (1993), found a significant correlation between imagery scales and measures of social desirability to suggestibility in the standard misinformation paradigm. Furthermore, research has consistently demonstrated a relationship between hypnotizability and suggestibility (Barnier & McConkey, 1992).
7. In related research, Hyman and Billings (1995) employed the false memory paradigm to examine four types of cognitive and personality differences in college students' false memory creation. They found that 27% of participants created false childhood memories in response to repeated presentations of a false event. Furthermore, scores on the Creative Imagination Scale (Wilson & Barber, 1978) and the Dissociative Experiences Scale (Berstein & Putnam, 1986) were significantly positively correlated with false memory creation. Surprisingly, neither the Social Desirability Scale (Crowne & Marlowe, 1960) nor the Tellegen Absorption Scale (Tellegen & Atkinson, 1974) were significantly related to false memory creation.
8. The research presented above demonstrates that people's reports for events are influenced by personality variables, particularly mental imagery. Memon & Stevenage (1996) noted that interviewers using the CI elicited more information from witnesses in comparison to an untrained group. However, the interviewers using the CI also elicited significantly more errors and confabulations than the untrained group (Memon, Bull, & Smith, 1995). Researchers and practitioners must ask themselves if more information is always better. In certain laboratory contexts, it may be appropriate to use every means possible to promote recall so that the nature of memory may be better understood. However, in forensic contexts, obtaining accurate information should be the interviewer's primary goal. I argue that the cognitive strategy of mental imagery be omitted from the CI until further research demonstrates that its benefits exceed its costs. Furthermore, I recommend that researchers consider the addition of an error detection component when developing interviewing techniques. At the very least, researchers and practitioners should note that some people have more productive imaginations than others.
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