Brain detects happiness more quickly than sadness

http://www.eurekalert.org/pub_releases/2009-06/f-sf-bdh061709.php

Public release date: 17-Jun-2009
Contact: SINC
FECYT - Spanish Foundation for Science and Technology

People make value judgements about others based on their facial expressions. A new study, carried out be Spanish and Brazilian researchers, shows that – after looking at a face for only 100 milliseconds – we can detect expressions of happiness and surprise faster than those of sadness or fear.
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