is automatically processed even when attention is directed locally, causes slow reaction time. Navon's study global precedence and his stimuli, or variations of it, are still used in nearly all global precedence experiments. Racial differences When presented with a Navon figure, there is a slight local preference for Caucasians, but East Asians show an obvious global preference and are faster and more accurate at global processing. The inclination towards global precedence is also evident in second generation Asian-Australians, but the correlation is weaker than that of recent immigrants. This could stem from the physical environment of East Asian versus Western cities, as the level of visual complexity varies across these environments. The tendency of Caucasians to process information "analytically" and Asians "holistically" has also been attributed to differences in brain structure. For some cognitive scientists, the stark contrast in cognitive processing trends across cultures and races suggests that all studies on cognitive perception should report participants’ races to ensure valid theoretical conclusions. Especially in experiments involving spatially distributed stimuli, neglected racial or cultural differences in visual perception could skew results. Cultural differences Global precedence is not a universal phenomenon. When Navon figure stimuli are presented to participants from a remote African culture, the Himba, local precedence is observed although the Himba show the capabilities for both global and local processing. This difference in precedence for Navon figure stimuli can be attributed to cultural differences in occupations, or in the practice of reading and writing. This finding dispels the idea that local precedence is a consequence or symptom of disorders, since the Himba is a normally functioning society capable of both global and local processing. Varying stimuli Stimuli are either meaningful or meaningless. For example, letters and familiar objects, like a cup, are meaningful, while unidentifiable and non-geometric forms are not. In both types of stimuli, the global advantage is observed, but the global interference effect only occurs with meaningful stimuli. In other words, when the global object is meaningful, the reaction time for identification of the local feature increases. This supports the theory that within global precedence, global advantage and global interference rely on two separate mechanisms. Global-local interference occurs as a result of automatic processing of global objects. The theory is that the global precedence effect has a sensory mechanism active in global advantage, whereas automatic and semantic processes are active in the interference effect. Age Cognitive processing varies