In the accompanying figure, the 13s in the top and bottom rows are identical, but the one on top is perceived as a letter while the one on the bottom is perceived as a number. Why might this difference in perception occur?

A) because of top-down processing effects
B) because we try to impose organization on top-down processes
C) because feature detection is a data-driven process
D) because we try to maintain a sense of constancy in perception

The difference in perception in this situation is likely due to top-down processing effects. The context in which the 13s are presented (e.g. the letters and numbers surrounding them) influences how they are perceived. Top-down processing refers to how our expectations, knowledge, and past experiences influence how we perceive and interpret sensory information. In this case, our prior knowledge and expectations about what letters and numbers should look like likely affect how we perceive the identical 13s in different contexts.