One result of traumatic experiences is that they can lead to involuntary flashbacks. These flashbacks are also known as "intrusive memories." Although many people simply try to not think about these memories, that approach is not typically effective. In the study described below, researchers attempted a novel intervention that capitalized on memory reactivation and reconsolidation.

Typically, when we remember events we "reopen" those memories (called reactivation). At that point the memories can change to include new information before being stored again (called reconsolidation). Work by James and colleagues (2015) explored whether traumatic memories could be disrupted by performing an interfering task after memories were reactivated. In other words, if people remembered images from a traumatic memory and then immediately performed a competing visual task (playing the game Tetris), the traumatic memories would weaken.

Participants (all of whom volunteered for the study after providing informed consent) watched video clips from movies depicting graphic violence. Participants then recorded the number of times images from the videos intruded on their thoughts over the next day. These "pre-intervention intrusions" are provided in the "Day_Zero_Number_of_Intrusions" column. After 24 hours had passed, all participants returned to the lab and participated in one of four conditions:

1. No-task control: These participants completed a 10-minute music filler task.
2. Reactivation + Tetris: These participants were shown a series of images from the trauma film to reactivate the traumatic memories (i.e., reactivation task). After a 10-minute music filler task, participants played the video game Tetris for 12 minutes.
3. Tetris Only: These participants played Tetris for 12 minutes, but did not complete the reactivation task.
4. Reactivation Only: These participants completed the reactivation task, but did not play Tetris.

All participants then recorded the number of intrusions over the next 7 days ("Days_One_to_Seven_Number_of_Intrusions").

Question 1

Some participants completed the study during morning sessions (1) whereas others completed the study during afternoon sessions (2). This information can be found in the "Time_of_Day" variable. Did participants' pre-intervention intrusions ("Day_Zero_Number_of_Intrustions") differ based on the time of day they completed the study?

Using our statistic decision tree, identify the most appropriate test.

Question 2

Perform your analysis and report your observed test statistic here. Remember to round to two decimal places.

Question 3

Based on your analysis, can you reject the null hypothesis?

Question 4

Write up your result in format, include mean and standard deviation if applicable.

Question 5

Your next task is to compare the four groups on the number of intrusions prior to returning to the lab for the intervention (Day_Zero_Number_of_Intrustions). Did they differ on this variable?

What is the most appropriate type of analysis for this question?

Question 6

Perform your analysis and report your observed test statistic here. Remember to round to two decimal places.

Question 7

Based on your analysis, can you reject the null hypothesis?

Question 8

Write up your result in format.

Question 9

Your final task is to explore whether the four groups differed in the number of intrusions during thethe 7 days following the intervention (Days_One_to_Seven_Number_of_Intrusions).

What is the most appropriate type of analysis for this question?

Question 10

Perform your analysis and report your observed test statistic here. Remember to round to two decimal places.

Question 11

Based on your analysis, can you reject the null hypothesis?

Question 12

Write up your result in format.

Question 13

Use the following process to export your output from the previous analysis and upload it here.

1. Select "Export results" in the pull down
2. Select "Computer," then select a place where you can find the file.
3. This will create an .html file, which you can upload here.

If you are using SPSS, you can export your results as a pdf file.

DATA

https://drive.google.com/file/d/1nZUVwsXWLfBvCZw3aBtm0jcz2LYFi4o9/view?usp=sharing