I See Psychology… Everywhere

Ok, So Does Weight Cause Cognitive Deficits?

Here‘s another article about predictors of cognitive deficits. Seems more weight is linked to poorer mental acumen. The headline is better than most, in that it doesn’t plead causality, but it still doesn’t clarify theory underlying the phenomenon, although some suggestions come up, and the author mentions a couple covariates that didn’t seem to explain what’s going on. Interesting stuff!

In general, the researchers found, people with a high body mass index (BMI) garnered lower test scores than those with a lower BMI. They also tended to show greater cognitive decline between the two test periods.

Factors such as age, education and general health did not seem to explain the link.


10 October 2006 Posted by | Cognitive, Research, Students | Leave a comment

Illusory Causality? “Teeth Improve Memory”

As I’ve noted before, I keep a collection of dubious causal claims, at least in terms of the headline. Here‘s another that caught my attention.

Well, there are multiple explanations for this odd-sounding claim.  The researchers claim that it’s the chewing process that brings blood to the brain, with obvious benefits.  Makes sense, but again, the headline doesn’t say that chewing improves memory.  So maybe the relationship is indirect.
Admitting that I haven’t read the original articles, there are a host of other possible explanations, depending upon the researchers’ techniques.  By the description in this pop press article, the study does not employ random assignment (seems a bit unethical to do such a thing), so the causal claim is a problem.  For example, my first reaction was that people with generally better health (i.e., nutrition, attention to healthy living) may experience better memory and better dental health.  Maybe genetics are the key, and those predisposed to suffer mental degradation are also predisposed to “dental degradation” if we can call it that.  Heck, it’s even possible that sugary foods, which we know contribute to tooth loss, also contribute to memory loss.

The point is that the researchers can’t rule that out, and although I’m confident that their article includes the relevant caveats, the press tends to simplify stories to make claims that the authors don’t intend.

Let’s repeat the mantra:  Correlation does not imply causation!

6 October 2006 Posted by | Research, Students | 1 Comment

Social Psychology in Bacteria

I recently heard a fascinating story on NPR of what one might call the social psychology of bacteria.  As Dr. Bonnie Bassler has demonstrated, bacteria seem to wait until they exist in a critical mass to do what they do.  Whether it’s to emit color, damage host cells, or whatever, they seem to recognize (on some level anyway) that they are pretty impotent individually, but in groups, they can have a pretty major impact on their world.

As lagniappe, Dr. Bassler’s comments about her life and lab illustrate a number of other principles, such as the impostor phenomenon, similarity and attraction, and a pessimistic explanatory style.  For example, she says that her students are similar to her in that when they find an exciting result, their immediate response is to wonder what they’ve done wrong.  Such impressive work; have a listen!

19 September 2006 Posted by | Comparative, Research, Social | Leave a comment

Correlation: Wine Bottle Dimple Depth & Price!

Itchy Squirrel has conducted extensive (and pleasurable!) research on the relationship between the depth of the dimple on the bottom of a bottle of wine (if you didn’t know there was a dimple, you’re not drinking very good stuff) and its price. So now you can see if your friends really care when they bring it over to you! A nice look at correlational research with a purpose! Don’t forget, correlation doesn’t imply causation!
Via Neatorama

31 August 2006 Posted by | Quantitative, Research | Leave a comment

Psyc of Religion or Confirmation Bias?

Neatorama has a nice roundup of recent religious “sightings.” Through chocolate, wood, and reptile skin, we either find revelations or selective perception–seeing what we expect (or want) to see. Enjoy.


31 August 2006 Posted by | Cognitive, Research, Sensation & Perception | 1 Comment

Erroneous Causality Argument

In my classes when I cover research methods, I show some newspaper articles that appropriately or inappropriately argue causality. I think it’s nice to show that journalists (and researchers) often read more into their data than they should, but it’s also nice to make the point about 3rd variables and reverse causality problems.

Here‘s a great example I got from Yahoo’s news site. The headline: Sexual Lyrics Prompt Teens to Have Sex. They provide little hint of the possibility that kids who have sex are drawn to music that contains such lyrics. Even the researchers make this assertion without acknowledging alternative explanations.

I’m not sayin’ that the claim is wrong, just that they don’t have the basis for the argument, at least beyond speculation.

7 August 2006 Posted by | Research, Social, Students | Leave a comment

Emo Phillips’ Operational Definitions

emo.jpgHow’s this for a nice illustration of the importance of operational definitions?

via Bob Harris

4 August 2006 Posted by | Research | Leave a comment