Chapter 17 Avital-Cohen activity

We will complete this activity in class, but if you would like to try out the task this activity focuses on, we would recommend to do this in advance. You can run the Avital-Cohen flanker task online here. It should take less than 15 minutes to complete.

For this activity, you will need to read parts of an empirical journal article. We think that it is really important that you start reading primary research literature early on in your course. As discussed in Chapter 2 of Beth’s book, empirical journal articles are the main way to communicate new findings in psychology. Not only do textbooks typically present a simplified picture, they also tend to lag behind new developments. This is not surprising given that it can take a few years before a new edition of a textbook is published. In addition, textbook authors frequently are not (and simply can not be) experts in all areas that their textbook covers. Thus, it might take years for them to pick up more recent developments that are not in their primary area of expertise12.

What is more, every primary research article is basically a lab report written by researchers. Therefore, if you want to develop an understanding of how lab reports should be written, it is a great idea to regularly read journal articles.

You might also want to go over the section “Reading the Research” in Chapter 2 of Beth’s book again before starting the activity. I completely agree with everything Beth says, but would like to take up the cudgels for the method section, which in my view is the most under-appreciated of all article sections. If you really want to understand what happened in a study, read the method section. If it is a well-written method section, it will provide you the deepest insights into what the researchers actually did.

The article you are about to read is about the flanker interference effect. The classic demonstration of the flanker interference effect was reported by Eriksen & Eriksen (1974). In the visual flanker task, there is a target that is usually presented in the middle of screen. Next to the target are the flankers. The target is relevant, the flankers are irrelevant. Similar to the Stroop task, target and flankers can be congruent, neutral or incongruent. The flanker effect refers to a slowing of RTs in incongruent relative to neutral or congruent trials and/or a decrease in accuracy in incongruent relative to neutral or congruent trials.

The classic version of the visual flanker task used letters. The version in the article below is slightly different from the classic version in that it uses letters and numbers.

If you would like to try out the task as a naïve participant, now is your final chance. If you read on, you will know too much about the study.

Please download the article by Avital-Cohen and Tsal.

Before you start reading the article:

  • Think about which sections of the article might be most relevant to answering the questions below, and focus on these sections.
  • Please note that to make it easier for you to identify the relevant parts of the article we have removed information pertaining to Experiment 2 from the article.

For Experiment 1 in Avital-Cohen and Tsal, please identify:

  • The design (i.e., between-subjects or within-subjects).
    • If between-subjects, posttest-only or pretest/posttest?
    • If within-subjects, was there any counterbalancing employed? If yes, how was this done?
  • The IV(s), and the levels of the IV(s) (see hint below if you get stuck)
  • The DV(s).
  • Examples of constants.


  • How many trials did the experiment consist of overall?
  • Can you think of a follow-up experiment to further investigate the effect?

Please work on this activity in pairs. Make sure you agree on one answer per question per pair.


Here is a hint for the question about the IV(s).

Note that there are two IVs in this experiment.

Note that there is a twist in how this article uses the flanker task: The flankers are either letters or digits. Critically, some flankers are ambiguous: They could be either numbers or letters (e.g., O could be the number 0 or the letter O). Avital-Cohen and Tsal show that these ambiguous letters only elicit an interference effect if participants interpret them as letters. This result is interesting because it is often believed that interference effects are automatic (i.e., they are not under voluntary control). Alternatively, one could say that researchers often believe these effects are a consequence of bottom-up processing (i.e., what happens is determined by the stimulus, not by your goals or the task instructions). On the contrary, Avital-Cohen and Tsal’s results show that top-down processing does influence the interference effect in the letter flanker task. This article is also a great example of how classic tasks can still be used to gain new insights!


Eriksen, B. A., & Eriksen, C. W. (1974). Effects of noise letters upon the identification of a target letter in a nonsearch task. Perception &Amp; Psychophysics, 16(1), 143–149.

  1. In this respect, edited books can be a better choice. Chapters in edited books are usually written by experts in a field.↩︎