Shouting head is a loud and aggressive person, particularly one who is a television pundit or commentator. 

“高呼者”指的是说话大声且咄咄逼人的人，特别是电视评论员或解说员。

This phrase is the loudmouth version of a talking head, a person, such as a newscaster or pundit, talking on television while shown in a close-up shot, an epithet that entered the language around 1976. 

这个说法是“接受电视采访者”的“高声讲话”版。新闻广播员或评论员等talking head（电视银幕上发言人的头部特写，指接受采访者）在电视上发表谈话，经常给予特写镜头。这个词在大约1976年就出现了。