How can I add more than one header objects to a request?

I am new to Gatling and Scala.

I don’t want to keep too many of header objects in my script as seen in scripts after recording. Most of the requests use same header values, except a few that may require more values to be supplied in headers.
So i want to keep only 1 header (something like: val headers_1 = Map(“Accept” → “image/png,image/;q=0.8,/*;q=0.5”)) that has values that are required by almost all requests and another header (something like: val header_2= Map(“security_token”->“some_value”) ) that have some unique values that i require in some particular request in addition to values that are present in header_1.

This can help to keep code clean.

How can do that?