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Canadian Family Physician logoLink to Canadian Family Physician
. 2011 Jul;57(7):799–800.

Part 8. Cognitive illusions

Greg Dubord 1,
PMCID: PMC3135449  PMID: 21753106

How do we help patients overcome cognogens?1 There are dozens of techniques, many of which will be outlined in future articles in this series. However, one technique particularly popular for self-help is the self-diagnosis of cognitive illusions.

Medical school illusions

Kindly examine the diagram in Figure 1. Who is bigger: the attending or the resident?

Figure 1.

Figure 1

A call schedule discussion

The attending and the resident are the same size, as evidenced by this artist’s rendition of a department social (Figure 2): Rest assured that you’re normal if you saw the fleeing attending as smaller than today’s assertive resident. Almost all of us—including program directors—are vulnerable to the monster resident optical illusion.

Figure 2.

Figure 2

The family practice social

Evolution’s view

Many optical illusions have evolutionary survival value, and thus many are hard-wired. We can train ourselves to be less influenced by such illusions, but we can’t eliminate them entirely.

The analogous errors of the cognitive system are what I call cognitive illusions (or distortions in orthodox cognitive behavioural therapy literature). Overgeneralization is a common cognitive illusion. It’s 20 000 BC and you’ve just witnessed your ex-wife being eaten by a sabretoothed tiger. You’d do well to overgeneralize about large cats with big teeth, although it might cost you the companionship of a great cave pet in your retirement years.

Endemic illusions

A cognitive illusion is a common thinking error or thinking trap. Cognitive illusions are endemic in the normal population, where they’re usually asymptomatic. To paraphrase Pasteur, “The cognitive illusion is nothing; the soil is everything.” Given the right circumstances—and for many of us, stress alone will suffice—cognitive illusions will happily hijack the emotional and behavioural systems.

Although most cognitive illusions are transdiagnostic—any given cognitive illusion can be part of virtually any psychopathologic syndrome—some are very typical of specific diagnoses (eg, mind reading in paranoid personality disorder, black-and-white thinking in borderline personality disorder, shoulding in obsessive-compulsive personality disorder).

It’s important to emphasize that we’re as prone to cognitive illusions as we are to optical illusions. We all have remnants of them—yes, even our chief residents. If this ubiquity is not emphasized to patients, many are otherwise apt to criticizing themselves for succumbing to them.

Table 1 outlines some common cognitive illusions.

Table 1.

Common cognitive illusions

COGNITIVE ILLUSION DEFINITION RESIDENT EXAMPLE ATTENDING EXAMPLE
Emotionally reasoning Jumping to incorrect conclusions based on your feelings I feel like a bad doctor [“therefore” I am a bad doctor] I feel angry [“therefore” this resident must be up to something]
Fortune telling Presuming to know the future I just know I’ll never master the brachial plexus This resident’s destined to raise the world’s malpractice fees
Mind reading Presuming to know what someone else is thinking I just know my call partner is mad at me [he’s actually just exhausted] This resident thinks I’m an idiot [she’s actually just intimidated]
Overgeneralizing Overgeneralizing from the facts at hand I didn’t get the preceptor I wanted—my career is ruined! I missed that coccidioidomycosis — I belong in Doctor Jail
Personalizing Taking things too personally That memo was targeted at me! [his charts are actually more current than average] That resident is very uncooperative [she’s actually worried sick about her mother’s cancer]
Polarizing Seeing things too absolutely (all-or-nothing, black-or-white) Either I get into ophthalmology or my lifestyle spouse will leave me This kid’s either gonna be an Osler or a Shipman
Shoulding Excessive self-criticism (sometimes introducing morality when none is warranted) I should be as sharp after 36 hours on call as after a surfing vacation in Hawaii I must make all the applause-worthy diagnoses

In practice

Here are 3 ways to use the cognitive illusions in practice.

1. Ad hoc

Simply point out and define cognitive illusions in passing.

Pt: I’ll never get another job.

Dr: It’s definitely a challenging time. But let’s not “fortune tell.” We can’t presume to know the future. One day at a time, OK?

2. Handout

Many patients readily see themselves in the cognitive illusions handout available from CFPlus.* Indications are broad: most patients suffering from excess emotionality derive some benefit. A daily skimming proves both entertaining and therapeutic for most. But remember to emphasize that cognitive illusions are normal and not grounds for increasing self-criticism.

3. Thought records

A cognitive illusions handout is a central part of the thought-record tool. Details will be reviewed next month.

Acknowledgments

I thank CBT Banff 2011 participants Raymond Allen, Michele Benedictson, Leo Lanoie, Sadia Shakil, Patricia Verones, Laurene Willox, and Tony Yang for their helpful comments, and Ozlem Yucel for her inimitable artwork.

Footnotes

*

The cognitive illusions handout is available at www.cfp.ca. Go to the full text of this article online, then click on CFPlus in the menu at the top right-hand side of the page.

Next month: Thought records

Reference


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