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You meet your first love—maybe in high school, maybe college, maybe later. You throw your whole heart into the relationship; the person is your sun, moon and stars. He’s handsome, funny, and smart; she’s everything you ever dreamed of.
And then they break your heart. You grieve. You hurt. You think you’ll never recover. But finally, one day—long after you’ve picked up the pieces and met your true soul mate—you run into your ex.
And one thought runs through your mind: What did I see in him?
The same person who sparked a thousand fantasies in the early throes of romance can leave us cold once we’ve taken off our rose-colored glasses. We know her looks haven’t changed but somehow—to us—she seems like a faded, smaller, less appealing version. Or perhaps we notice a few things we were reluctant to admit before, like his penchant for scouting the room instead of making eye contact when we talk, or his tendency to focus on himself as the topic of conversation.
Of course, we know why our perception of the ex is different: The way we see someone is influenced by how we feel about the individual. We know, without question, that it’s not our ex who has changed; we have.
But what if this shift in perception (and emotion) occurred with no obvious explanation?
Who Are You?
Imagine this scenario: You’ve always had a close relationship with your mom. Six months ago, you were in a terrible car accident that left you in a coma for three months. She stood beside you every step of the way. Yet, while you’re recovering physically, something is not right. Your mom looks the same. She wears similar clothes and has similar mannerisms. She knows your pet peeves, your favorite foods, and your closest friends. And yet, you don’t feel anything when you’re with her. She looks the same but she doesn’t feel the same.
You search for an explanation—and then begin to notice little things that bother you: Perhaps she forgets to put your soup in your favorite cup one day. Perhaps she puts her purse down in a different spot than usual. Suddenly, it all makes sense: The person who claims to be your mom is not who she says she is. She’s been replaced by an impostor.
Disconcerting Delusions
The belief that impostors have replaced friends and family members was first discovered in 1923 by French psychiatrist Joseph Capgras. He described a 53-year-old Parisian seamstress who became convinced there were strange creatures known as "sosies" kidnapping those around her. These creatures imprisoned her loved ones underground as they plotted to steal all her property. She believed a sosie had replaced her husband and, in fact, filed a complaint requesting a separation from the court, attesting:
“If this person is my husband, he is totally unrecognizable, he is transformed. I certify that this so-called husband that they are trying to foist on me in fact ceased to exist 10 years ago.”
Capgras hypothesized that something had gone wrong with the patient's facial recognition, losing any sense of familiarity when she saw those she thought she knew. This discord between her thoughts and her feelings led her eventually to assume those around her were impostors.
We still don’t know for sure what causes this delusion of misidentification, but recent theories tend to support Capgras’ initial thoughts. Neurologist V.S. Ramachandran, for example, believes a malfunction between the brain’s visual cortex and the emotional feeling of “connection” or “familiarity” causes the sufferer to think he or she is seeing a perfect duplicate instead of the real deal. The eyes are reporting correctly, but the emotions are off. The conclusion: Here’s an exact impostor. Offering further support, some patients with so-called Capgras delusions are able to recognize a loved one on the telephone even though they continue to misidentify the individual in person. This suggests that there are different neural pathways for auditory and visual recognition.
Individuals who develop Capgras delusions are typically suffering from either schizophrenia (the delusions are thought to develop in about 4% of patients diagnosed with schizophrenia); organic brain dysfunction arising from severe head trauma; or a neurodegenerative disease such as Alzheimer’s. The “impostor” is always a person (occasionally a place) with whom the sufferer is familiar. Sadly, the delusion is not correctable by experience or reason. But they can sometimes be treated with antipsychotic medication, especially when the sufferer is schizophrenic.
Our eyes aren’t the only way we recognize someone we love. We also recognize them through the emotional connection we have to them. In fact, the importance of that emotional connection to our facial recognition may rise as the strength of the connection increases. This might explain why, in Capgras delusions, the person most often believes loved ones to be the impostors; when the emotional connection fails, the sufferer believes that their loved ones just cannot be who they appear to be.
At the very least, Capgras delusions are disturbing for both the person experiencing them as well as those around him or her. The “impostor,” in particular, is often viewed with hostility and resentment.
As we’ll see in the next article, some features of Capgras delusions, when present, can be dangerous. The sufferer may begin to view the “double” as a threat and, out of his or her misguided beliefs, resort to murder.
