These deformations affect the shape of our brows – altering how raised, rounded, pointed, oblique, lowered, furrowed, etc. they become. Such changes help us identify different facial expressions. 

While the principles of movement are stable across these actions, their impact on eyebrow shape varies from individual to individual. Generally, we are able to recognize facial motions with reasonable certainty; however, we are not immune to potential biases.

the room for bias