All non-anxious people are alike, but every anxious person is anxious in their own way – to paraphrase Tolstoy.

Two broad kinds of anxiety people can experience are social anxiety and generalized anxiety. Social anxiety disorder, as the name suggests, is a fear of being scrutinized or judged by other people. Generalized anxiety disorder is excessive worry about anything, really, ranging from health to money.

Both social anxiety disorder and generalized anxiety disorder share the fact that they’re anxiety disorders. Fundamentally, the experience of both disorders is about being anxious. But people with each disorder worry about different things, leading researchers to ask: how different are these two disorders, really?

Several studies have looked at this question and have found both ways the two disorders are distinct and attributes the disorders have in common.

Most recently, for example, a study by the National Institute of Mental Health found that people with social anxiety and generalized anxiety differ in terms of how optimistic they are.

People without anxiety disorders tend to have an optimism bias. That is, they tend to be overly optimistic and think good things are more likely to happen to them than to other people. It turns out that people without generalized anxiety disorder don’t have this bias – they don’t see themselves as any more likely to have positive events occur in their lives. Meanwhile, people with social anxiety, also known as social phobia, resemble people without generalized anxiety in that they still have an optimism bias.

A 2015 study found that certain brain differences between social anxiety disorder and generalized anxiety disorder are already evident in 8- to 10-year-old children. In particular, children with social anxiety tend to have an exaggerated neural response to monetary losses while children with generalized anxiety tend to have a reduced response. One explanation suggested by the authors of the study is that people with social anxiety and people with generalized anxiety both process rewards atypically, but in different ways.

Still, there’s plenty the two disorders have in common. For example, research published earlier this year showed that people with both social anxiety and generalized anxiety disorder tend to be especially intolerant of uncertainty.

In the end, the somewhat unsatisfying answer the research gives us is that social anxiety and generalized anxiety seem to be very different in some ways and very different in others. Untangling these similarities and differences will be important for finding treatments and interventions that target specific anxiety disorders more effectively.

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