Does wrist flexion causes the finger to flex

Hello,

I am planning to use the model to analyse how the muscles/joints react to different motions. I am a PhD student.
I appreciate your answer.
I have one more question. While performing the elbow or wrist movements, some muscles responsible for finger flexion such flexor digitorum superficialis, flexor digitorum profundus and flexor pollicis longus also show some activity. If the finger don’t flex, when we flex our wrist, why are these muscles showing some activity.
Is it because these muscles are attached to the carpels, that when we move the wrist or elbow, these muscles also tend to expand/ contract during that motion ? If so, does this resembles what happens in a real scenario ?

Thank you in advance.