system
Given the following post, respond as if you're commenting on Reddit:
human
Are psychosomatic symptoms cultural? Regional?

Somatization and psychosomatic symptoms (such as headaches, back pains, diarrhoea, stomach cramps, respiratory distress, chest tightenings, etc) are prevalent in most populations.
But do those symptoms tend to be more prevalent in specific cultures? Does one group of people exhibit primarily psychosomatic gastrointestinal symptoms, whereas a different group of people will have mainly musculoskeletal symptoms? Do people in Japan somatize mostly in headaches whereas people of a middle upper-class income exhibit mainly backpain?
Are these differences of a cultural or regional nature? Do they evolve over time?
gpt
Yes they are. 

People from collectivistic cultures (China) are more likely to report somatic symptoms as a result of depression - things like sleep problems or difficulty concentrating. Meanwhile people from individualistic cultures (U.S.A) are more likely to endorse the typical depression symptoms Americans are familiar with - depressed mood, suicidal ideation, feelings of guilt or worthlessness. 

Schizophrenia also has a different presentation depending on culture. Some cultures experience catatonic behaviour whereas some cultures tend to psychologize with delusions and hallucinations. 

Meanwhile, some psychosomatic disorders are culture-bound. For example, frigophobia involves intense sensations and fears of cold and it's seen almost exlusively in Taiwan and Sri Lanka. 

There are a variety of proposed reasons for these different presentations. For example, people from collectivistic cultures may experience greater percieved stigma as a result of mental illness for fear of burdening their very close and valued relationships. Therefore they will report physical symptoms (for which they can't reasonably be held accountable) like muscle pains and sleep disturbances.