In Dr. Barrington's research, which group is likely to have the least susceptibility to the Müller-Lyer illusion?

The group that is likely to have the least susceptibility to the Müller-Lyer illusion is the African Zulus. Research has shown that cultural factors influence perception, and the Müller-Lyer illusion, which involves misjudging the lengths of lines due to the presence of arrows or fins at the ends, is often more pronounced in individuals from Western cultures.

The Zulu people, who are not typically exposed to the architectural and visual stimuli prevalent in Western societies, are less likely to be influenced by the illusion. This is because their cultural experiences shape how they interpret visual information. The westernized experiences of other groups, such as Americans, often lead to a greater degree of susceptibility to such illusions due to their familiarity with certain shapes and perspectives.

In contrast, individuals from non-Western cultures, like the Zulus, tend to have perceptual frameworks that do not align with those of Western populations, making them less susceptible to being misled by illusions like the Müller-Lyer. Therefore, the African Zulus represent a group with cognitive processing less affected by this particular visual illusion due to their cultural background and the visual environment in which they have been raised.