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Interesting research is being presented at the 2003 Society for Neuroscience Meeting that shows the processes that take place in the brain when memories are established can be as important to the development of false memories as the process of memory retrieval. Previous research shows that specific parts of the brain are more active when a true memory is being retrieved than when a false memory is being retrieved, potentially providing a neural label by which to understand the differences between true and false memories.
Since we literally cannot record and store all of what we learn and experience, memories can be fragile and subject to distortion . People often mistakenly claim to remember having seen a word or object that is similar to something they saw earlier. Such false memories can have an even greater impact when they manifest in such a way that entirely novel events are implanted into an individual’s memory. Such an individual can willingly retrieve these completely false memories, such as being lost in a mall, with surprisingly vivid and specific details.
Neuroimaging techniques can help determine if the neural processes driving this retrieval of inaccurate memories are different from those that drive the retrieval of accurate memories. The hope is that neuroimaging can help determine the various potential sources of false memories. Daniel Schacter, PhD, and his colleagues at Harvard University have looked at neural activity associated with the creation of false memories. Previous studies had focused on neural activity associated with the retrieval of false memories. It has been shown that the right fusiform cortex is involved in encoding the exact visual details of objects and the left fusiform cortex is involved in more general processing, An experiment was designed to test the role of the right fusiform area in avoiding the formation of false memories for objects similar to those seen previously but not exactly the same. The fMRI study revealed that there is a different activation of brain regions involved in visual processing during true versus false memory.
In an related study by David Beversdorf, MD, and colleagues at Ohio State University, researchers looked at formation of false memories when a "critical lure" similar to a geometric shape previously seen was later viewed. "Twenty-three participants were shown images of geometric figures in 24 sets on 12 slides. Each set of slides showed different geometric shapes that were different in size, color, and position. Participants were asked to remember as many of the slides as they could. After seeing the 12 slides in each set, participants were shown five more slides and asked whether or not they had seen them in a previous set. Two of the five slides had in fact been shown, two had not, and one was designed to be strongly related to all of the other slides shown but had not been shown previously. This slide was called a critical lure."
Results were suprising in that participants believed they had seen an image that they had actually not seen 59 percent of the time. This suggests that people can be easily persuaded to believe that they have seen something they did not see. The significance of this study and others using visual stimuli shows that false memories can develop during nonverbal tasks. It is suggested that such findings may have implications for those with autism. High functioning autistic individuals can actually perform better than others on verbal false memory tasks. However, because atypical language processing is a defining feature of autism, it remains to be seen whether this unusually good performance for false memories can extend to nonverbal tasks.
11:38:22 PM 
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