Reclining alters the way our brains respond to anger

More than a dozen studies employing electroencephalography (EEG) and repetitive transcranial magnetic stimulation (rTMS) methods have found that the left prefrontal cortex is activated to a greater degree than the right prefrontal cortex during the experience anger, especially when the anger was accompanied by approach inclinations. By contrast, several fMRI studies failed to corroborate these findings. Curious about these divergent findings, Eddie Harmon-Jones and Carly Peterson at Texas A & M university cleverly noted that EEG and rTMS studies are done with the participant in the upright position whereas fMRI studies are performed with participants lying down. They hypothesized that activity in the left prefrontal cortex reflects not just anger but the approach orientation associated with anger and that approach motivations may be diminished while laying down and this might account for the absence of heightened activity in the left prefrontal cortex in the fMRI studies.

To test this hypothesis, they asked college undergrads to spend 10 mins writing an essay supporting their position on a topic such as smoking in public and that these essays would then be evaluated by another participant. They were hooked up to EEG sensors and some were reclined while others remained upright. Then the experimenter took the essay into an adjacent room where the participants essay would supposedly be evaluated by another participant. All reclined overheard negative comments about their essay and personality while half of the participants in the upright condition heard mildly positive comments. Immediately following the feedback, 2 mins of EEG were recorded.

The researchers indeed found that the insult-upright condition produced greater relative left frontal activity than the insult-reclined condition.

It is important to note that body position had no impact on self-reports of anger.  Insults make people feel anger whether reclined or upright but the response of the brain and the impact on our body appears to be quite different. It would be very interesting indeed if future studies measured physiological indicators and compared these between participants in supine or upright positions. Perhaps insulted people in the reclined position feel anger but don’t suffer the deleterious effects of hostility to the same extent as insulted people in an upright, ready-to-fight posture.

Harmon-Jones, E., & Peterson, C. K. (2009). Supine body position reduces neural response to anger evocation. Psychol Sci. EPub

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