Experiment1Summary

= = =// Now You See It; Now You Don't: Inhibiting Recall and Recognition of Scenes //=

__Introduction__:
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 * The biggest question being considered by the researchers in this article are the effects that "postevent information" or PEI can have on inhibiting the retrieval of information from memory. Postevent information is the information that is presented after an event has occurred. Previous findings on PEI have indicated that PEI can alter and add aspects to a memory. This article will focus more on whether or not PEI can make aspects of memory less accessible. This research is important when considering eyewitness accounts of an event and the impact it could possibly have on a police investigation (Write, Loftus, Hall 2001).

__Procedure__:

 * __Participants__:
 * 115 undergraduate volunteers are shown 13 colored drawings depicting a man and a women going on a date.


 * __2 Critical Scenes__:
 * 1) WAITRESS taking a couples order (critical to restaurant script)
 * 2) Man playing a GUITAR (not critical to restaurant script)


 * Each participant saw 12 of the 13 drawings on a computer screen. Half saw the WAITRESS scene but not the guitar, and the other half were shown the GUITAR and not the waitress scene.
 * Participants were then asked to redraw each scene using a black pen on separate sheets of paper.
 * One week later participants were brought back into the lab.
 * 1/2 were in a control group and given a filler task.
 * 1/2 were placed in 1 of 2 "storybook" conditions.

Table 1. The different conditions for the WAITRESS scene. As depicted by Write, Loftus, Hall (2001).
 * = **Description** ||= **Original Presentation** ||= **Postevent Information** ||
 * = //Control Add// ||= No W shown ||= No storybook (filler task) ||
 * = //Add// ||= No W shown ||= W in book ||
 * = //Control Omit// ||= W shown ||= No storybook (filler task) ||
 * = //Omit// ||= W shown ||= No W in book ||


 * The participants in the "storybook" conditions were given someone else's drawings from the previous week and asked to tell a story about the "date" depicted in the storybook as if they were telling it to a 6-year old girl.
 * There were 2 versions of the storybook:
 * 1: WAITRESS no guitar --> given to participants who did not originally see the waitress scene.
 * 2: GUITAR no waitress --> given to participants who did not originally see the guitar scene.
 * All participants were then given a 20-minute filler task and then asked to provide a detailed description of the //original drawings presented the first week//. (RECALL)
 * Using a yes or no recognition test participants were then questioned about whether or not certain actions occurred during the original presentation. (RECOGNITION)

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__Results__:
Table 1. The different conditions for the WAITRESS scene. As depicted by Write, Loftus, Hall (2001). Table 2. The percentages for free recall and recognition //of the critical scene//. As depicted by Write, Loftus, Hall (2001).
 * = **Description** ||= **Original Presentation** ||= **Postevent Information** ||
 * = //Control Add// ||= No W shown ||= No storybook (filler task) ||
 * = //Add// ||= No W shown ||= W in book ||
 * = //Control Omit// ||= W shown ||= No storybook (filler task) ||
 * = //Omit// ||= W shown ||= No W in book ||
 * <  ||||= **Free Recall** ||   ||||= **Recognition** ||
 * <  ||= **Not Recalled** ||= **Recalled** ||   ||= **Not Recog.** ||= **Recog**. ||
 * < //Control Add// ||= 94 ||= 6 ||  ||= 64 ||= 36 ||
 * < //Add// ||= 80 ||= 20 ||  ||= 54 ||= 46 ||
 * < //Control Omit// ||= 33 ||= 67 ||  ||= 16 ||= 84 ||
 * < //Omit// ||= 56 ||= 44 ||  ||= 34 ||= 66 ||
 * **FREE RECALL:**
 * The "Control Add" and "Control Omit" groups helped the researchers identify that the participants were able to properly encode and remember the "critical scenes." You can see by comparing Table 1 and Table 2 that those in the control group that were not shown the PEI storybook were more often then not able to freely recall the critical scene.
 * The second important piece to be interpreted is how the alternative groups were effected by the PEI. When comparing the "Control Add" and "Add" as well as the "Control Omit" and "Omit" the results in Table 2 suggest that PEI //can add// a scene to a memory, as well as inhibit the recall of a scene.


 * **RECOGNITION:**
 * The control groups in the yes or no recognition results indicate that:
 * The "Control Add" group who had not been shown the critical scene, only 36% recognized one.
 * And those in the "Control Omit" group that were shown the critical scene, 84% recognized the scene.
 * The most important piece was found when comparing the "Control Omit" and the "Omit" groups. Using the recognition test with the "Control Omit" group recognition of the critical scene increased to 84% from 67% in the recall test. Within the "Omit" group 66% recognized the critical scene up from a previous 44% in the recall test.


 * Conclusion:**
 * The storybooks manipulated a participants memory of the critical scenes observed. When information was added to the storybook but not present in the original scenario it was added to recall. It was also more difficult to recall information from the original scenario when it wasn't in the storybook. In terms of recognition those that were shown the storybook were less likely to recognize the scenes they were shown in the original scenario.