A similar study done decades back had actors do facial expressions that mirrored classic feelings. Then these actors also were asked to think thoughts which reflected those feelings. Not surprisingly, just putting the face in those expressions showed EEG patterns similar to thinking the emotions. In short... Put on a happy face and you'll feel happy. Wear the face of a fighter and you're halfway to the mindset of a fighter.
Glare in the eyes with fast hands
Ponder this study a bit. They just chose one facial expression. But it demonstrates the principle rather remarkably.
Cosmetic Use of Botulinum Toxin-A Affects Processing of Emotional Language
David A. Havas,
Arthur M. Glenberg,
Karol A. Gutowski,
Mark J. Lucarelli, and
Richard J. Davidson
David A. Havas, Department of Psychology, University of Wisconsin–Madison, 1202 W. Johnson St., Madison, WI 53706-1611 E-mail: email@example.com
How does language reliably evoke emotion, as it does when people read a favorite novel or listen to a skilled orator? Recent evidence suggests that comprehension involves a mental simulation of sentence content that calls on the same neural systems used in literal action, perception, and emotion. In this study, we demonstrated that involuntary facial expression plays a causal role in the processing of emotional language. Subcutaneous injections of botulinum toxin-A (BTX) were used to temporarily paralyze the facial muscle used in frowning. We found that BTX selectively slowed the reading of sentences that described situations that normally require the paralyzed muscle for expressing the emotions evoked by the sentences. This finding demonstrates that peripheral feedback plays a role in language processing, supports facial-feedback theories of emotional cognition, and raises questions about the effects of BTX on cognition and emotional reactivity. We account for the role of facial feedback in language processing by considering neurophysiological mechanisms and reinforcement-learning theory.
As written up in the Wall Street Journal...
Emotional Processing: Botox appears to impair emotional processing, according to a study in Psychological Science. Researchers recruited 40 women who were scheduled to receive cosmetic injections of botulinum toxin-A, which paralyzes the facial muscle we use for frowning. Before injection and again two weeks afterward, the researchers tested how quickly the participants could read sentences conveying happiness (an example: "You spring up the stairs to your lover's apartment"), sadness ("You open your email inbox on your birthday to find no new emails"), and anger ("Reeling from the fight with that stubborn bigot, you slam the car door"). It took the women an average of four to five seconds to read each sentence. After Botox, they took about 200 milliseconds longer to read angry and sad sentences than before the injection. Reading times for happy sentences weren't affected. The results show that emotional processing is aided by facial feedback, the researchers said.
Caveat: The researchers used only reading time as a proxy for emotional processing, but did not measure the participants' own emotions or reactions.