When people immigrated they experience depression. Depression A brain disorder characterized by persistently depressed mood or loss of interest in activities

I highlighted that you should define the terms that mean define them. for example.
” when people immigrated they experience depression. Depression A brain disorder characterized by persistently depressed mood or loss of interest in activities.”
or
“when people immigrated they experience depression.which is a brain disorder characterized by persistently depressed mood or loss of interest in activities.”
dont define every psychological term, define only the ones in the list.

resources you may need.
1)A History of Psychology in Letters- Ludy T. Benjamin
2)a brief history of modern psychology- Ludy T. Benjamin