Experiment+2+Summary

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

__Introduction__:

 * Experiment 1 successfully showed that by getting someone to re-tell a version of a story, it can affect their free recall and recognition of an entire scene from a brief vignette. This experiment will investigate whether having people imagine parts of a past event can have a similar effect. In this experiment, participants saw an event, they then later imagined several parts of the event, and finally were tested on their memory for the event.

__ Procedure: __

 * __Participants__:


 * 162 volunteer undergraduate participants were randomly allocated to one of four conditions: Control Omit, Control Add, Omit, and Add.


 * Two versions of a video clip of a drunk-driving incident was shown to participants.


 * The Control Omit and Omit groups' film included a scene where a policeman stops a car with a drunk driver, the person then drives off and later in the clip the car ends up hitting a person.


 * The Control Add and Add groups saw the same film, excluding the part where the drunk driver gets pulled over and drives off.


 * __1 Critical Scene__:
 * 1) The officer pulls over a drunk driver and the drunk driver then drives off.


 * For the two experimental conditions (Omit and Add), the participants were presented with a brief description of each scene from the video ans asked to imagine it. The participants then rated how easy or difficult the scene was to imagine.
 * The Add condition participants, who weren't originally shown the critical scene, were asked to imagine it along with all the other scenes.
 * The Omit condition participants, who had originally saw the scritical scene, were not asked to imagine the critical scene, but were asked to imagine all the other scenes.


 * This was a self paced imagination task, with most participants taking around 5 minutes. After a 4 minute filler task, participants then free recalled everything they could about the event sequence and answered 19 yes/no recognition questions about whether or not certain actions, including the critical scene, had occured during the original video presentation.

__Results:__

 * = **Description** ||||= **Free Recall** ||||= **Recognition** ||
 * ||= Not Recalled ||= Recalled ||= Not Recognized ||= Recognized ||
 * = //Control Add// ||= 98 ||= 2 ||= 85 ||= 15 ||
 * = //Add// ||= 85 ||= 15 ||= 59 ||= 41 ||
 * = //Control Omit// ||= 3 ||= 98 ||= 3 ||= 98 ||
 * = //Omit// ||= 18 ||= 83 ||= 10 ||= 90 ||
 * This table shows the percentages of people in each condition who recalled the critical scene.


 * __FREE RECALL FINDINGS:__**


 * Only 2% of people in the Control Add condition (shown the video without the critical scene) reported the critical scene
 * 98% in the Control Omit condition (shown the video with the critical scene) reported the critical scene.
 * This shows that the two groups were very accurate in their free recalls.

The second comparison is between the Control Add and the Add conditions (who each did not see the critical scene).
 * 15% of the people in the Add condition gave a report that referred to the critical scene, as opposed to the 2% in the Control Add group.

The third compatison is between the Control Omit and the Omit conditions (who each did see the critical scene).
 * 98% of people in the Control Omit condition reported the critical scene, as opposed to only 83% in the Omit group.

__**RECOGNITION FINDINGS:**__

The recognition findings refer to the answers to the True/False question in regard to the critical scene.


 * 98% of those in the control group who saw the critical scene recognised it, while only 15% of those who were not shown the scene said that they recognized it. The control participants were extremely accurate.

The second comparison looks at determining whether the imagination task can increase false recognition.
 * 15% of those in the Control Add condition said that they recognized the scene, while over 40% of the people in the Add condition //falsely// recognized it.

The third comparison looks at whether or not the manipulations could reduce accurate recognition.
 * 90% of those in the Omit condition recognized the critical scene (although they had not been asked to imagine it along with the other scenes).

__Conclusion:__
The control groups were very accurate in their free recalls and recognition of the critical scene. Fifteen percent of people in the Add group who had not originally been shown the version including the critical scene, but instead were asked to imagine it, reported having seen the critical scene. This is larger than the 2 percent of the Control Add group that had not originally been shown the critical scene, nor were asked to imagine it. Perhaps the most surprising finding in experiment 2 is that over 40% of the Add group, who again had not originally been shown the critical scene, but were asked to imagine it, //falsely recognized// the scene in the questionaire.