Meaning of "or" here ?

Hi, In the following sentences, I don't understand whether the schools refer to same thing or not.

I mean how should I understand the meaning of "or"? This or that? Or same as "in other words"?

Is there any way to distinguish the usage?

Thanks~

It seems that when the human brain is stressed, the focus on visuals is heightened. This is likely a survival
adaptation. However, this means that teachers instructing in high-risk schools or in schools where there is a high concentration of poverty should maximize the use of visuals and visual cues during instruction.