In this simple mnemonic example, the clench phase corresponds to convergence and the release to divergence.

FORBES: The Pittsburgh Six: The Template for Innovation

This action was to clench either their right or their left hand into a fist.

ECONOMIST: Reading the brain

Both techniques were able to see the brain acting to clench a volunteer's fist in his dream in exactly the way that it does when ordering fist-clenching in reality.

ECONOMIST: Reading the brain

The poetry, written by Maya Angelou, clumps along with a confessional earnestness that makes you clench your fists and try not to laugh.

NEWYORKER: Poetic Justice