Being around complainers at work is not only unpleasant, it's bad for your workplace brain and performance. Brain researchers have long known that the adult brain is surprisingly plastic -- we can strengthen synaptic connections through repetition, for example, to improve our memory. But a new study using functional MRIs found that negative words actually stimulate the areas of our brain associated with perceptions and cognitive functioning.

Why does this matter? Negative thinking at work, or being around negative coworkers, can decrease your workplace performance. Chronic exposure to negative messages from complainers will reinforce negative thinking and behaviour.

Fascinating new research proves that the brain can't distinguish fact from fiction, so if you keep hearing negative messages, your workplace behaviour will change to fit these new perceptions -- and not in a good way!

Here are nine ways to defend yourself against workplace complaints -- yours and others' -- so you can rewire your brain and boost the occurrence of positive thoughts and behaviours:

1. Become self-aware.
When you feel a complaint coming on, no matter how trivial, stop yourself. You can't delete the thought, but you can revise it before saying it aloud. So instead of saying, "Oh, that's exciting, but they would never give me that assignment," you might say, "That's the type of challenge I'm ready to tackle once higher-ups take notice of me."

2. Redirect the conversation.
When you participate in negative dialogue with a complainer, you'll walk away feeling depleted. Instead, take control of the direction the conversation is going. If he says, "I hate Mondays. The weekend isn't long enough," counter his negative thoughts with a positive set of images: "I'm glad I rested up this weekend! Now I'm ready to dig into that big project."

3. Smother a negative thought with a positive image.
If a negative thought pops into your mind, immediately input a different image. This is the process of "neurogenesis" -- creating new pathways in your brain that lead to positive behaviours. So if your inbox is filled with urgent to-dos and you think to yourself "I'm already exhausted," immediately conjure up a pleasant image, say, an after-work run in the park with your dog.

4. Don't try to convert others.
When trapped in a toxic group of complainers at a meeting or around the coffeepot, simply choose silence. Let their words bounce off you and not penetrate your mind while you think of something pleasant. If you try to stop them, you may end up alienating yourself and becoming a target.

5. Distance yourself when possible.
When coworkers start criticizing someone or something and you can escape, excuse yourself and take a break somewhere quiet -- preferably outside in the fresh air. Think of something pleasant before returning. You have to take this seriously, because negative people can and will pull you into the quicksand.

6. Wear an invisible "mentality shield."
Imagine that an invisible shield like a glass cloak made of positive energy descends from the sky and lightly covers your whole body. You can see perfectly well through it but it protects you from others' negative words and emotions.

7. Create a private retreat.
Mentally retreat to a private, special place in your imagination. Visualize a peaceful setting in your mind -- say, a sunny trail next to a meadow brook, or a sailboat on a lake. When you're stuck with a coworker who is spewing vitriol, you can appear as if you're listening while you distract your mind with a visit to your peaceful place.

8. Transfer responsibility.
On occasions when you're pressed against a wall while someone rants about all the injustices in their life, throw the responsibility back at them by saying, "So what do you intend to do about it?" In most cases, complainers don't want a solution nor do they want sympathy. They just want to vent, and this tactic will stop them in their tracks.

9. Forgive your lapses.
Everyone complains sometimes. Your favourite team loses. Your computer crashes. Deadlines pile up. It's human to vent once in a while. Be kind to yourself after a lapse into victimhood and complaining -- and then start afresh. The less frequently you complain, the more time will pass between lapses into negativity. This is how rewiring the brain works.

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