Psychological research on the principles of learning has most directly influenced the development of

psychoanalysis.

behavior therapy.

humanistic therapy.

The answer is: behavior therapy

Behavioral therapy studies how the environment around individuals affect their behavior and the things that we can do in order to change the unwanted behaviors.

The solutions from behavioral therapy is often applicable to individual learning as well ... Rather than sticking with one single method for all individuals as their main method of learning, principles of learning put environment around the individuals and their behaviors into account. By knowing this, we can create a more effective way of learning for different individuals.