Memory implantation is a technique used in cognitive psychology to investigate human memory. In memory implantation studies researchers make people believe that they remember an event that actually never happened. The false memories that have been successfully implanted in people's memories include remembering being lost in a mall as a child, taking a hot air balloon ride, and putting slime in a teacher's desk in primary school. Memory implantation techniques were developed in the 1990s as a way of providing evidence of how easy it is to distort people's memories of past events. Most of the studies on memory implantation were published in the context of the debate about repressed memories and the possible danger of digging for lost memories in therapy. The successful implantation of memories in people's minds has implications for therapy and legal settings. Successful memory implantation Published studies The first formal studies using memory implantation were published in the early 1990s, the most famous being "The Formation of False Memories" (commonly referred to as the "Lost in the Mall" study) by Loftus and Pickrell. The basic technique used in this study involved asking family members of a participant to provide narratives of events that happened when they were young and then add another event that definitely had not happened. The participants saw these four narratives and were told to try to remember as much as possible about each event. Across a number of studies using memory implantation, about 37% of people have come to remember parts of or entire events that never actually happened. Other studies have expanded on this paradigm by introducing photos instead of narratives. Wade and colleagues found that 50% of people came to remember details of a hot air balloon ride that never happened, after seeing a manipulated photo depicting the event. Later it has been argued that photos by themselves do not produce more false memories than narratives, but that both methods have the power to successfully implant false memories. Real photos have also been found to increase the creation of false memories. In a study by Lindsay and colleagues people were shown a childhood photo from the same time period as the false event. Seeing the photo resulted in more false memories, even when the photos did not depict the actual event. In a study with children 1999 Pezdek and Hodge found that it was easier to implant a memory