Due to their immediate survival significance, negative emotions enjoy priority processing in the brain. This is one of nature's peculiar ironies, because positive emotions are actually more important to long-term survival. You have a better chance of living a longer, higher quality life if you experience more positive emotions than negative ones. You are certainly better off in the long run admiring the lovely green of the rolling hills, but you won't make it to the long run if you don't notice the snake lurking in the grass in front of you. Thus our brains are hard-wired to scan the immediate environment continuously for threat, which is why it takes so much effort to slow down and smell the roses.
The hard-wired threat-detector embedded in our central nervous systems makes a lot of sense in terms of keeping us safe from physical threats. Unfortunately, it has been hijacked in modern times to include threats to the ego. When ego grows, emotional pollution flows.
You can think of the ego as a compilation of the ways you prefer to think and feel about yourself combined with how you prefer others to think and feel about you. If a person needs to think of himself as important, he is likely to manipulate the impressions of others to make them think he is important. Psychologists refer to these attempts to manipulate the impressions that other people have of us as "impression management." Emotional polluters invest heavily in impression management. But they also have a safety-net when their efforts at impression management fall short. The polluter who fails to get others to think he's important will simply regard them as unimportant. Thus he feels more important by downward comparison to those who don't think he's important.
Emotional pollution becomes a major problem when assaults on the ego engage defense systems meant to keep us physically safe. That's why ego-threats can seem like life-and-death situations. (How else could a term like "death before dishonor" make sense?) This transfer of defenses dedicated to the survival of the species to the defense of the ego gives emotional pollution its terrible foothold on our psyches. Emotional pollutants make us feel put down, shut out, belittled, or diminished, whether or not we are consciously aware of the feelings.
Ironically, the defenses we develop to protect the ego against emotional pollution end up creating more of it, if we try to prevent others from making us feel put down, shut out, belittled or diminished by putting them down, shutting them out, belittling or diminishing them. The temptation is to dismiss the emotional polluter who needs to feel more important than you: "He's just a jerk." But then you're doing the exact same thing as he -- making yourself feel more important by regarding him as unimportant. That may defend your ego against his unfair assault, but when you react to a jerk like a jerk, what does that make you? Emotional pollution is an ego-defensive display of (usually subtle) psychological aggression that requires others to defend their egos in response. Thus it is inexorably self-perpetuating.
Although the ego is the point of attack, the toxic effects of emotional pollution go beyond the psychological. The defenses it invokes, which evolved to keep us physically safe, are emergency systems powered by corrosive stress chemicals that were never intended for use every day, not in anything like the frequency required to cope with emotional pollution. Thus we pay a high physiological price - in addition to the exorbitant psychological one -- for dealing with emotional pollution on a daily basis.
