What is the meaning of 心理活动 here?
You are right about 心理 and 活动 and 心理活动.

The key to understand this sentence is 就...而言, which means with regards to/in terms of/based on.


  就一般心理活动而言 = With regards to the general psychological process, ...


The verbiage is not very precise in Chinese. My understanding is 'general' here refers to people in normal mental state.

The whole sentence means 'From psychological standpoint, (normal) people are not accepting praise at all time'.