Past research has focused on the extent to which people will falsely remember things that did not happen to them. In the current set of experiments, the rate at which twins disputed the ownership of a past event was investigated. Questioning the ownership of a memory for a past event varies slightly from past research on false memories and false memory implantation, in that the validity of the memory is not in question, but rather, who the protagonist of the event was. By this logic, one of the twins actually was the central character of the event in question. As such, one of the twins must be in error about their role in the past event. 

Experiment 1 

The issue of central concern of the first experiment is simply the number of disputed memories elicited by a semantic cueing task. Pairs of twins were presented with a set of 45 cue words, and each member of the pair was asked to provide a description of an event specific memory cued by the presentation of the words. 

Results
Of the 20 sets of twins, 14 disputed ownership of a memory with their twin, producing a total of 36 disputed memories. Of these disputed memories 21 were first disputed during the experimental session. Two points of interest arise out of this first study. First, the age of the twins when a disputed memory occurred ranged from 5 to 14 years old age. Thus, these events occurred during a time when twins would have had many shared events, and prior to the stage of life when self- identity is thought to form. Secondly, most of the disputed memories were negative in nature. As pointed out in the article, past research has demonstrated that affectively charged memories are experienced as being more vivid than less affectively charged memories. 

Experiment 2

This paradigm allows researchers another manner in which to investigate the qualia accompanying accurate and inaccurate memories. Forty sets of twins were recruited to participate in the present experiment. Of these 40 sets of twins, 26 (25 females, and 1 male; 65%) reported having disputed a memory with their twin. Of these 40 sets of twins, 20 actually participated in the remainder of the experiment. Twins were asked to report a total of 10 memories, five of which could be disputed. Then, twins completed an autobiographical memory questionnaire, consisting of 15 statements about the quality of the memory, for each of the 10 memories. Participants first completed questionnaires for the disputed memories. 

Results
Again disputed memories were recalled from late childhood and adolescence. However, this is not informative because nondisputed memories were typically from this same time period. Twins were more likely to rate disputed memories as being higher on memory qualities associated with recollection, imagery and emotion (see Table 4). These dimensions of memory qualities are of particular interest given different theories of autobiographical memory and memory more generally. 

Experiment 3

Finally, the rate at which individuals who are not twins would experience disputed memories was addressed. A questionnaire inquiring about the occurrence of disputed memories was distributed to 69 college students. Of these students 6 reported having disputed the ownership of an event with another person in the past.