The short answer is: you don't know. These examples are inherently ambiguous.
The only way to know definitively is from the context and the reader's interpretation. For example, in the sentence:
The red car and bunny were both there.
Since a car can be red and a bunny (generally) can't be, it's safe to assume that red only modifies car.
But consider the sentence:
The happy boy and girl were both there.
There is no way to be certain as to whether just the boy is happy or both children are happy.
If it's essential to be clear on the meaning, the sentence must be reworded.
With that said, I would personally interpret your example sentence as:
Many studies have noted (social functionality) and (contribution of (helping behaviors, volunteering and altruism) towards individuals, groups or institutes).
This is not the only, definitive interpretation—just my own.