Yesterday Jay Z launched a music streaming service - "Tidal". Of course it's in its infancy - but this innovation has as a primary goal of putting more money in the musicians' pockets - even at the expense of less profit for the company. Jay Z has a little help from family (Beyoncé) and a few of his friends - Kanye West, Madonna, Jack White, Jason Aldean, Deadmau5, Rihanna, Daft Punk, J. Cole, Nicki Minaj, Alicia Keys, etc. - but make no mistake Jay Z is at the helm. And although most feel this video is slickly produced - it's full of insincerity and thin veneers.
The palm-down, hand gesture Jay Z repeatedly uses here is termed "The Dominant Spider". This illustrator is used by those with an alpha emotional tone. It tends to be displayed primarily by alpha males and somewhat less-so with alpha females. The up-and-down motion amplifies this emotion (He strikes down on the table multiple times [0:45-0:47 and 1:19-1:22]). When directed toward the audience - it grows even more aggressive and is then called "The Claw" (and in the vast majority of scenarios, the claw is too aggressive). The dominant spider is not as dominant or as negatively received as the palm-down, closed-fingered or gesture. The dominant spider should be used sparingly - only for a short moment or two in order to assert dominance, confidence and authority. As with most alpha body language, it's very often over-used - which doesn't take much - and thus backfires and becomes offensive and specifically will project arrogance as well as condescending and patronizing emotions (Notice that Kanye is gazing at his hand).
See also:
Nonverbal Communication Analysis No. 3142: Mike Pence - Governor of Indiana interview with George Stephanopoulos & the Religious Freedom Restoration Act - What Makes Gov. Pence Look Worse?
Negotiation Secret No. 702: The Dominant Spider - Muammar Gaddafi (Moammar Gadhafi)
Negotiation Nonverbal Communication Secret No. 1059: Santorum's Dominant Spider
Nonverbal Communication Analysis No. 1871: Barack Obama Explains His "Private Sector is Doing Fine" Comment - The "Dominant Spider" vs.The "Split-Finger Fastball"
Nonverbal Communication Analysis No. 2132: Variations on a Theme - The Palm-Forward Dominant Spider (The Claw) vs. The Split-Finger Fastball
Nonverbal Communication Analysis No. 2499: NYPD Commissioner Ray Kelly, "Stop and Frisk" and a Body Language Display of Dominance
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