Are Neutral Faces Actually Neutral?
Christopher Philip

We can hide and conceal our true emotions – this is no secrete. But does painting on a neutral, expressionless face, really convey neutrality or absence of thought? Is a neutral face really emotionless? Is a neutral face devoid of meaning?

Toward uncovering the significance of the neutral face, a team of researchers led by Fernando Carvajal, Department of Biological Psychology and Health, University of Madrid, looked at the inner workings of the brain.

By presenting subjects, whom were hooked up to magnetic resonance imaging, with neutral and emotional faces, it was possible to show that similar brain areas were activated. This suggests, say the researchers, that neutral faces and emotional faces both share a common neural substrate.

Neutral faces specifically activated the cerebellum, frontal and temporal areas, while emotional faces involve the cuneus, anterior cingulated gyrus, medial orbitofrontal cortex, posterior superior temporal gyrus, precentral/postcentral gyrus and insula.

According to the researcher, “like other facial expressions, neutral expressions are usually assigned some emotional significance.”

That said, this particular study found that neutral faces evoked a much greater activation of circuits which indicate a “more elaborate cognitive processing.” That is, when presented with an emotionless faces, our brain must work harder.

“To conclude,” say the researchers “the results of this work suggest that emotionally inexpressive faces are not perceived very differently from emotional facial expressions and their recognition requires at least a partially shared neural network. However, neutral faces activate other frontal and temporal brain regions that could reflect a more elaborate cognitive processing not required for facial expressions of basic emotions, and emotional faces have been found to activate some specific limbic brain areas.”

Therefore, the next time you view a neutral face, or use one yourself, don’t think it’s meaningless – in fact, it likely means quite the opposite and commands even greater attention and processing than simply using an appropriate emotional expression.

Resources

Carvajal, Fernando; Sandra Rubio; Juan M. Serrano; Marcos Ríos Lago; Juan Alvarez Linera; Lara Pacheco and Pilar Martín. Is a neutral expression also a neutral stimulus? A study with functional magnetic resonance. Experimental Brain Research. 2013. 228:467–479. DOI 10.1007/s00221-013-3578-1