Final answer:
Shepard and Metzler's image rotation experiment was pivotal in cognitive psychology for its demonstration of mental rotation and spatial representation, suggesting the presence of complex mental processes involved in visual stimuli interpretation.
Step-by-step explanation:
Shepard and Metzler's "image rotation" experiment was influential and important in the study of cognition because it provided empirical evidence supporting the presence of spatial representation and mental imagery in cognitive processes. Their experiment showed that the time it took participants to determine whether two images were the same or mirror images increased linearly with the angle of rotation. This suggested a kind of mental rotation was taking place, which indicated that the cognitive processing of visual stimuli involved spatial manipulation in a mental space, rather than just a static recognition of patterns or shapes.
Furthermore, their findings contributed significantly to the development of cognitive psychology, providing a challenge to behaviorist approaches that were dominant at the time which often disregarded unobservable mental processes. The experiment also highlighted the brain's ability to create dynamic mental simulations, which is crucial for various cognitive tasks, including navigation, problem-solving, and understanding of three-dimensional structures.