Priming research is multifaceted and criticism cannot be universally applied to all this research. One widely used approach is masked priming. Having studied masking in many experiments for almost forty years and well familiar with relevant literature I can assure that im many cases those who USE masking (incl. in priming studies) do not know all the subtleties and pitfalls common to this paradigm. There are surprisingly many potential sources of artifacts and confounds when one uses masking of the stimuli that are hoped to become subliminal (i.e., not consciously experienced) by the masking procedure. From tens of the possible places where one may overlook these artefacts I mention only few here. 1. Not alltrials in masked presentations lead to equal perceptual experiences of the prime-mask interaction. In some trials masking is severe, in some other masking is not strong; this is despite that physical parameters of stimulation are the same. Thus the effects can be based on trials where masking somewhat fails. 2. In an interaction of successive stimuli masked input has an effect also on how the masking stimulus looks like or influences behavior. Although a preceding stimulus (e.g., prime) may be subliminal itself, it has had an effect on mask appearance whereby mask takes over the role of the source of effect, often through a semi-conscious appearance. 3. Methodologically, it is challenging and without an ideal solution to disentangle perception and immediate memory. Some trials may involve experienced perception of the prime, but also a fast forgetting of it. 4. Mask may change SOME perceptual characteristics of teh prime, but not all; hence primes may have effect indirectly, but still as consciously perceived aspects of stimulation. 5. And so on... In a nutshell, before beginning to use masking as a method it is advisable to carefully and substantially study this field in order to be better prepared to avoid artefacts. And an endnote: in my lab when we have tried to obtain priming effects, we have always failed when true masking has been granted. (This does not mean that a masked stimulus can not influence how fast and how mask itself is perceived.)

I think he is right.

Priming research is multifaceted and criticism cannot be universally applied to all this research. One widely used approach is masked priming. Having studied masking in many experiments for almost forty years and well familiar with relevant literature I can assure that im many cases those who USE masking (incl. in priming studies) do not know all the subtleties and pitfalls common to this paradigm. There are surprisingly many potential sources of artifacts and confounds when one uses masking of the stimuli that are hoped to become subliminal (i.e., not consciously experienced) by the masking procedure. From tens of the possible places where one may overlook these artefacts I mention only few here. 1. Not alltrials in masked presentations lead to equal perceptual experiences of the prime-mask interaction. In some trials masking is severe, in some other masking is not strong; this is despite that physical parameters of stimulation are the same. Thus the effects can be based on trials where masking somewhat fails. 2. In an interaction of successive stimuli masked input has an effect also on how the masking stimulus looks like or influences behavior. Although a preceding stimulus (e.g., prime) may be subliminal itself, it has had an effect on mask appearance whereby mask takes over the role of the source of effect, often through a semi-conscious appearance. 3. Methodologically, it is challenging and without an ideal solution to disentangle perception and immediate memory. Some trials may involve experienced perception of the prime, but also a fast forgetting of it. 4. Mask may change SOME perceptual characteristics of teh prime, but not all; hence primes may have effect indirectly, but still as consciously perceived aspects of stimulation. 5. And so on... In a nutshell, before beginning to use masking as a method it is advisable to carefully and substantially study this field in order to be better prepared to avoid artefacts. And an endnote: in my lab when we have tried to obtain priming effects, we have always failed when true masking has been granted. (This does not mean that a masked stimulus can not influence how fast and how mask itself is perceived.)

Talis, this is a brilliant analysis of yours - so much can happen just when attempting to mask.

Although I don't work using priming procedures I agree with Talis Bachmann and am inclined to believe that in his letter Kahneman didn't mean to target priming experiments in general. Priming can be a robust phenomenon, and such robustness is due also to a long history of replications in cognitive psychology, psycholinguistics, attention studies, etc. Rather, social/affective priming, the IAT (implicit association test) paradigm and variations thereof, have been blossoming in the last two decades to study the most diverse aspects of social behavior and attitudes, sometimes blindly entrusting the methodology, as if it were a golden standard. However, I also know that in social psychology do exist many studies that explored the limitations of these methods - thus everybody was warned...

I don't think it's correct to tar everyone with the same brush, perhaps Kahneman should have better separated the wheat from the chaff, in other words he should have been even more explicit on the good services that priming studies offered to experimental psychology since many decades.

Dear Research Gate Followers,

I started studying priming paradigm recently and I was overwhelmed by the amount of various literature on this topic. I agree that priming cannot be considered as a uniform line of research. Could you recommend me some review articles, books, or meta-analyses that deal with the definition of priming, effects of priming on memory and theoretical frameworks that offer explanations of these effects? Thank you.

Dear Tamara,

Here are some quick refs you may find useful:

Bargh, J.A. (2006). Agenda 2006: What have we been priming all these years? On the development, mechanisms, and ecology of nonconscious social behavior. European Journal of Social Psychology, 36, 147–168.

Bargh, J.A., & Chartrand, T. (2000). Studying the mind in the middle: A practical guide to priming and automaticity research. In H. Reis & C. Judd (Eds.), Handbook of research methods in social psychology (pp. 253–285). New York: Cambridge University Press.

Gawronski, B., & Payne, B.K. (Eds.) (2010). Handbook of Implicit Social Cognition. N.Y./London: Guilford.

Hassin, R.R., Uleman, J.S., & Bargh, J.A. (2005). The new unconscious. New York: Oxford University Press.

Kinoshita, S., & Lupker, S.J. (Eds.) (2003). Masked Priming... N.Y./Hove: Psychology Press.

Loersch, C., & Payne, B.K. (2011). The situated inference model:… Perspectives on Psychological Science, 6(3), 234-252.

Yet, I keep warning that not all priming research results must be necessarily valid because of the many methodological pitfalls. (And let us remember that some of the recent cases of scientific fraud /cf recent issues of Nature and Science/ are related to implicit social cognition/motivation research.

Thank you for your answer, it has been most helpful, ecpecially Bragh and Chartrand paper from 2000.

Talis, in your concluding remark you rightly hint that unusually many cases of fraud or sloppy methodology have come from the area of priming research. Why is that the case? Because priming effects are so surprising and easily made it to the media?

I still do hope and believe that fraud is by far less frequent case compared to the problems with methodology and questionable methodology based conclusions from the experiments. (A sideremark: in a recent paper published in Frontiers in Psychology (Consciousness...) Overgaard and associates also show how some aspects of the stimuli may be made unconscious while other aspects may remain indirectly accessible -- this is another example how "subliminal" may be actually partly supraliminal stimulation. In priming similar things may happen.) And of course, the topic of influencing people's behaviour subliminally easily exceeds media threshold as well as is related to the promise of many citations when a paper on priming or some other implicit social-perception effect is published.

Again: when in the students worksthat I've been supervising initially some priming has been seemingly established, the more careful and methodologically stricter replication typically has failed. But Kahneman may be right in noticing that priming effects are subtle, instable and difficult to obtain.

Thanks Talis, I do agree with all three of your suggestions.