Suppression of emotion impairs memory

Reuters News

When we keep a 'poker face' under emotional stress we may also undermine short-term memory, according to researchers.

"Emotion suppression has its costs," write Drs. Jane M. Richards and James J. Gross of Stanford University in California. Their findings are published in the August issue of the Personality and Social Psychology Bulletin.

Numerous studies have suggested that the suppression of strong emotion triggers changes in cardiovascular activity. However, the effect of a 'stiff upper lip' on cognitive (thought) processes has been less clear.

In their study, Richards and Gross asked groups of female undergraduates to view slides of men with mild to disturbingly severe physical injuries. Half of the women were asked to "behave in such a way that a person watching you would not know you are feeling anything at all."

Participants were then given a 'surprise' memory-recall test focused on data presented during the slide show.

The investigators found that "(emotion) suppression led to poorer memory." Women who were told to curb outward displays of emotion scored lower in terms of short-term recall than women who were allowed to wince, gasp, or exhibit similar displays of revulsion.

This inhibition in memory occurred at similar levels whether subjects viewed pictures of mildly-injured or severely-injured men. According to the researchers, this may mean that "emotion suppression may be an all-or-none process," wherein memory is impaired to a similar degree regardless of the level of emotion suppressed.

Subsequent experiments indicated that although emotional suppression does cause changes in cardiovascular activity, these changes are "not responsible" for concurrent lapses in memory.

The researchers speculate that attempts at hiding emotion trigger an "attentional shift" in the brain -- directing limited neurological resources away from memory-processing. Confirmation of this theory will require further study, the authors conclude.

SOURCE: Personality and Social Psychology Bulletin 1999;25:1033-1044.