In the 1944 movie Gaslight, the young woman (played by Ingrid Bergman) is tricked by her husband into thinking she is going insane. In fact, he wants to hide the murder he committed so he can find the victim’s missing jewels. When his wife says she sees the gaslights dim (after he was looking for the jewels in the attic), he tells her she is just imagining it. Similarly, he tells her she has done things she didn’t do. He keeps this up until she no longer trusts her own mind. Fortunately for her, a detective arrives on the scene who is able to solve the mystery.

The term gaslighting is used by psychologists to describe the use of deflection and distraction and blame by one person to hide some truth, or to benefit in some way, at the cost of another.

As a couple therapist, I see many couples with issues around betrayal. This could involve affairs, polygamy, a secret offshore bank account, or anything hidden by one partner that is then revealed. The reveal can lead to emotional trauma in the victim. Why? Because the victim’s brain must now continually review history and reorganize his or her experience to fit the new information. This can be extremely disorienting.

Betrayal is exacerbated by the lying inherent in it. The longer a person lies about something, the worse the insult to the victim’s brain, and the more difficult the healing process. Perhaps the most insidious form of lying is the practice of gaslighting. In that case, the perpetrator not only tries to cover up the truth, but to refocus the blame on the victim as a means to escape from his or her own guilt.

For example, “You’ve got to up your medications. You’re paranoid,” a man says to his partner when she says something in therapy that indicates she is close to discovering his secret. He wants us to shift and talk about her paranoia, so his secret won’t come out. Or another example. “You have problems with your memory, and you know that. I think you’re mixing things up. That never happened,” a woman says to her husband when he feels confident in his knowledge about something she has done, and she wants to instill doubt.

As a therapist, I view gaslighting as particularly sinister because it goes further than lying and covering up. Recovering from betrayal is not easy for couples. Recovery from the emotional trauma of gaslighting is much more difficult.

Why bring this up now? Because gaslighting is not limited to relationships between two people; it can occur at a national level. We as Americans are in a committed relationship with our leaders. We expect our government to be truthful with us. We rely on facts being true when the government passes along information. Our sanity as individuals as well as a nation depends on a climate of basic trust.

We are not living in a movie: if we are repeatedly lied to in the political arena, there are consequences to our national emotional health, whether we realize it or not. Individuals who have a personal history of being betrayed or lied to may be especially vulnerable, but every person is at risk. Everyone’s brain is traumatized when it is forced to continually reconcile what it knows to be fact with falsehoods it is being told.

You may think it doesn’t matter; that we’re all able as adults to discern the facts. But that is to underestimate the very real effects of gaslighting. The perpetrator gaslights because he knows how effective and disorienting it is. He does it because it is a powerful way to manipulate others. He does it because it takes the focus off whatever he is doing that he doesn’t want you to know about. And he may well get away with it because there is not always either a detective or a therapist—or in this case, a news outlet or a governing body—available to help pick up the pieces.