We all have personality quirks. But occasionally, a person may behave so eccentrically and erratically that they cannot function in regular life situations. It might seem easy to identify a person who behaves oddly. They might be chronically suspicious of everyone and everything. Or they may be so much of a perfectionist that they are unable to complete even simple tasks. However, to truly say someone’s personality is not ‘normal,’ we must have some assumptions about what a ‘normal’ personality looks like.
It’s more difficult to describe a normal personality than, say, a normal heart. If someone has a heart attack, we might say that an artery became clogged, blocking the flow of blood. In other words, we know that something caused their heart to deviate from normal functioning. But what does the normally-functioning human personality look like?
When a person shows longstanding, highly unusual patterns of behavior, they sometimes qualify for what psychologists call ‘personality disorders.’ Researchers looked at all of the criteria for personality disorders and “flipped” them to see what the expectation of normalcy was behind them. For example, one of the criteria for schizoid personality disorder (a disorder marked by emotional coldness and a solitary lifestyle) is that the person does not want or enjoy close relationships. If you flip that around, you see that there is an expectation that a ‘normal’ person will want and enjoy close relationships.
Some might say that having close relationships is typical behavior for humans, and thus a fair assumption about what normal is. However, consider a few more flipped ‘criteria’ for normalcy:
-Be only mildly, if ever, depressed
-Be trusting in social situations
-Be sexually modest
Depending on your world views, you may find fault with some of these ideas of “normal,” or disagree that “normal” is even desirable. Some argue that a “normal” personality is just one that conforms to the values held by a particular culture. In fact, one requirement for the diagnosis of a personality disorder is that the behavior deviates remarkably from what that person’s culture would expect of them. This creates problems in creating reliable diagnostic categories, because someone could be identified as having a disorder in one culture, but be considered normal in another.
This does not mean that personality disorders are only cases of cultural mismatches between a person and their environment. Studies have found both psychological and biological differences when comparing people with diagnoses of personality disorders with people with no diagnosis. For example, differences have been found in how people with personality disorders react to emotions, or how they process sensory information. There is evidence that there can be disorders in personality, but we must take great care in how we define and discuss them. If we are going to call something a disorder, there needs to be more at the root of it than just culturally inconvenient behavior. In creating criteria for personality disorders, psychologists and researchers must be clear to differentiate actual psychological issues from mere expectations that are based on culture or personal values. They must clearly define what “normal” is, and transparently decide what they are basing that definition on.
Postscript: The manual used for diagnosing psychological disorders is soon to be updated, and substantial revisions to the definitions of personality disorders are expected. However, to have a personality disorder, we must still have an idea of what an “undisordered” or normal personality looks like. Thus, the issues mentioned in this post may remain problematic.
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