Michael Perkins

A study reported in the August 2009 issue of the Journal of Investigative Dermatology seems to show that patients with psoriasis have a diminished capacity to recognize facial expressions of disgust.

When male psoriasis patients were shown images of disgusted faces, fMRI data showed significantly reduced activity in the insula cortex compared to age-matched male controls. No significant differences in brain response were found when the psoriasis patients viewed neutral or fearful faces.

These results were corroborated by the test subjects' performance on the facial expression recognition task (FERT). Psoriasis patients were less able than controls to identify various intensities of disgusted facial expressions. They were, however, able to identify fearful and sad expressions as well as the control group.

The investigators hypothesize that the psoriasis patients' inability to process disgusted facial expressions protects them from stressful emotional responses.

This appears to be a striking example of what Cordelia Fine calls the "vain brain."

The vain brain presents a "softer, kinder reality" that preserves the individual's positive self-evaluation. While it troubles philosophers, for the rest of us it is vastly more comfortable that we can only know ourselves and the world through the distorting prism of our brains. Freud suggested that the ego "rejects the unbearable idea," and since then experimental psychologists have been peeling back the protective layers encasing our self-esteem to reveal the multitude of strategies our brains use to keep our egos plump and self-satisfied. (Cordelia Fine, A Mind of Its Own,  p. 6, emphasis mine)