Homework #2: Part 2: Stroop Effect (CogLab)

This homework has two parts. You will complete both this lab and the Visual Search lab for this assignment. For this lab, you will participate in one version of Stroop's classic study.

Remember to turn off any pop-up blockers before running this module. The lab report that you'll write up for this module will include information from both your individual data and the overall class data. Before beginning, read all of these instructions.

1. You will complete the Attention module on Stroop Effect. Read the relevant section in the Student Manual, then go to CogLab online. Read the online description of the study carefully (pay careful attention to the instructions, including which keys are used for which responses), then login and complete the module.
2. Be sure to click "Yes" to add your individual results to the global results. The class (PSY 622) results will appear. Ignore those for now. Instead, click on the link on that results page that allows you to view your individual results. Print out your individual results (the trial-by-trial data will give you information from which you can deduce details about the design of the study, but you don't need to print out your trial-by-trial data, only the summary table of means. To avoid printing all the other stuff, go to Print Preview on your browser (on the File tab) and check to see which page has the info you want -- it will probably be page 1 -- then go to the Print option and select only that page under the Print Selected Pages option).
3. In order to view the global results, you'll need to go to the“User Information” page by logging in on the CogLab page and then clicking “Access Account.” You’ll see that this lab is listed in the “Labs you have finished column” (If you want to see your individual data again, just click on “Get your data”).
4. To view the global results for the experiment, first highlight the name of the module (Stroop Effect), then click on “Get global averages.” The global averages are compiled from the data from all the people who have completed this module to date. Print out these global results, too. You may want to see how the students in PSY 622 did; if so, click on "Get group averages."
5. The remainder of this assignment involves writing up a lab report of your results. Your report will be about 4-6 pages long and roughly follow APA style with a brief Introduction, a Hypothesis section, a Method section, a Results section, and a Discussion section. The paper also includes a References page. Finally, attach the printouts of both your individual and global results to the paper. The assigned article that accompanies this module is Stroop (1935).
   • First, provide an Introduction, giving the reader a theoretical context for the phenomenon under study. While you may cite your textbook as a source, you may use other relevant sources that you find (including the original Stroop article). Include citations to the relevant literature.
   • Next, provide a Hypothesis section. In this section, first identify the dependent variable(s) and the independent, grouping, subject, and/or predictor variable(s).Then provide a clear statement of the hypothesis (or hypotheses) being tested in this experiment. Be sure each hypothesis is relevant to the concepts/theories being discussed in class and to what is illustrated in the experiment and is stated in terms of how each dependent variable is expected to change as a function of the independent/grouping variable(s). Do not simply copy (or slightly paraphrase) the hypothesis or research question provided in CogLab. You are to formulate and phrase each hypothesis in your own words.
   • Next, provide a Method section with its relevant subsections. Because you know the sample size from the global results but you do not know anything else about the characteristics of those participants (e.g., average age, gender distribution, etc.), it does not make much sense to have a separate Participants section in the lab report when you would only have one sentence under it. So, for this and all subsequent modules, you will instead have a Participants, Materials and Procedure section instead (be aware that this is for lab report purposes only. APA style for a manuscript, thesis, etc. requires a Participants section separate from the Materials and Procedure section).
     • For the Participants part of the section, use the global data to identify the sample size. For the Materials and Procedures portion, describe the types of materials used (be as specific as possible as to type of stimuli, number of types etc), the procedure for administering the stimuli (number of trials, order of trials, etc), and the general design (e.g., the conditions). Use the information from the manual and online CogLab pages as well as your experience with the experiment itself (including inferences you can make about procedures by looking at the trial-by-trial data) as sources for specific information on materials and procedures, but do not simply copy the method descriptions from those sources (that's plagiarism). Rework and reword the descriptions into your own wording and organization. Remember, a good Method section describes the method in such a way that a person who hasn't been in the experiment could design and run it based on your description.
   • Next, write a Results section. As part of the results, use the global averages to construct a bar (column) graph of the global reaction time data. Call the graph Figure 1 and give it a descriptive title. Give the X and Y axes appropriate labels. Be sure you refer to the graph in your Results section (you cannot attach figures or tables to a paper unless you also refer directly to them in the text). Use Excel to create the graph and follow the graphing guidelines given out in class. In the narrative portion of this Results section describe the patterns of both your individual results and the global results. Use the CogLab printouts to compare the pattern of your individual results to that of the global results and to discuss the similarities. Attach copies of the printouts of both your individual results and the global averages to the paper.
   • In the Discussion section for this module, you'll talk about how your results relate to previous study of the phenomena, including if the hypotheses were supported. In addition, you are to address all of the following issues (write the section as a coherent narrative including relevant citations, not as a list of answers to questions):
     1. How do the data relate to the theory that, in fluent readers, word meaning is processed automatically?
     2. Would you expect to see Stroop interference if the color words were written in a language that the person did not know? Why or why not?
     3. The "control" condition in this study is actually an enhancement condition; that is, when the word name and ink color match, ink naming RT is even faster than when when the stimulus is a nonword or color patch (the standard control condition). How might that pattern of Stroop results (ink naming fastest for word/ink match, slowest for word/ink mismatch, in between for nonword/ink) be explained in terms of automatic spreading activation?
     4. Stroop interference designs have also been used to evaluate other types of phenomena. For example, phobic patients generally show slower ink naming times (Stroop interference) when asked to name ink colors of words related to their phobia compared to phobia-unrelated words. How might you account for this finding?
   • Be sure to include a References section at the end giving full APA-style references for all the sources cited in your report. Remember, you cannot cite anything in your References that you have not actually read yourself.
     • If you use sources in addition to your textbook, the CogLab manual, and the Stroop article, include a photocopy of each article (or book chapter) along with your lab report.

Go to CogLab.