Individual differences are to universal principles as the perspective is to the perspective.

humanistic;neuroscience                                  

Explanation:

Humanistic perspective: The term humanistic perspective is defined as an approach in psychology that focuses on an individual's empathetic behavior and therefore sees the good in human being's behavior. It focuses on improving an individual's self-actualization tendency or self-image as it forms the basis of making the person feels worthwhile.

Neuroscience perspective: The term neuroscience perspective is also referred to as biopsychology, and is explained as understanding human behavior through different biological processes. It states that an individual's behavior can be expressed via brain functions and the way hormones and neurons interact with each other.

answer; overt behavior;