A Level Psychology OCR Practice Exam

In the Gibson and Walk experiments, one significant method employed to control biases was the use of patterned surfaces, which played a crucial role in the study of depth perception in infants and animals. By using patterned surfaces, the researchers ensured that a rich visual stimulation was available, allowing participants to perceive and react to depth cues without being influenced by other environmental factors. This factor helped maintain a controlled setting where the primary focus was on how infants interpreted visual information regarding depth rather than other sensory inputs.

The option about using different lighting conditions and the one suggesting testing in varying heights of cliffs may influence the perception of depth but do not directly relate to controlling biases in how participants responded to the visual stimuli. Similarly, having infants wear blindfolds would hinder their ability to perceive the patterns altogether, making it counterproductive to the aim of the experiments.