Earlier today, Vladimir Putin arrived late to lunch at the United Nations. While later in the day, Mr. Putin and Barack Obama had an arranged, prepared and highly-posed meeting for the cameras - their first handshake in many months was much more telling.
In the image below (captured from 1:33 the video above) - we see a moment when the Presidents leans closer to each other - and although the Russian is blocked from our view here, the American President's lips are exhibiting what is known as an "Inward Lip Roll" (ILR). Note Obama's jaw is not clenched tightly, his lips however are rolled inward between his teeth. An inward lip roll is a signal that the psyche is attempting to suppress both the outward display of an emotion - as well as its internal crescendo.
While an ILR is more commonly seen in the context of negative emotions such as anger, frustration, disgust, etc. - it may also be seen repressing joy-happiness - when the public display of such emotion needs to be suppressed.
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