Repeated action creates a habit. We all know this.
But you may not know the way in which a pattern of thought -- say, habitual complaining -- literally re-writes the pathways of the brain.
Author Steven Parton wrote for Psych Pedia, via Inc., explains how ritual complaining is a contagious behavior -- both for the person that participates in that behavior and those around them.
"Throughout your brain there is a collection of synapses separated by empty space called the synaptic cleft," Parton writes. "Whenever you have a thought, one synapse shoots a chemical across the cleft to another synapse, thus building a bridge over which an electric signal can cross, carrying along its charge the relevant information you're thinking about."
In short, as we repeat thoughts, our brain rewrites its wiring to make it easier on itself to repeat those thoughts.
"Here's the kicker," he continues. "Every time this electrical charge is triggered, the synapses grow closer together in order to decrease the distance the electrical charge has to cross.... The brain is rewiring its own circuitry, physically changing itself, to make it easier and more likely that the proper synapses will share the chemical link and thus spark together--in essence, making it easier for the thought to trigger."
As complainers re-write their own brain, they also subconsciously lead those around them to mimic their behavior.
"When we see someone experiencing an emotion (be it anger, sadness, happiness, etc), our brain 'tries out' that same emotion to imagine what the other person is going through. And it does this by attempting to fire the same synapses in your own brain so that you can attempt to relate to the emotion you're observing. This is basically empathy. It is how we get the mob mentality.... It is our shared bliss at music festivals," Parton wrote. "But it is also your night at the bar with your friends who love love love to constantly bitch."
Negative emotions aren't just confined to the brain, though. Complaints release the stress hormone cortisol, and elevated levels of that "interfere with learning and memory, lower immune function and bone density, increase weight gain, blood pressure, cholesterol, heart disease," Parton wrote. "The list goes on and on."