Cultural Differences in Cognitive Processing Style: Evidence from Eye Movements During Scene Processing

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1 Cultural Differences in Cognitive Processing Style: Evidence from Eye Movements During Scene Processing Zihui Lu Meredyth Daneman Eyal M. Reingold Abstract The present study provided a partial replication of an influential study by Chua, Boland, and Nisbett (2005). By tracking the eye movements of North American and Chinese students when viewing pictures of naturalistic scenes, both studies demonstrated that the North American students fixated more on the focal object in the scene, whereas the Chinese students fixated more on the background. However, these cultural biases in viewing patterns did not appear to be related to later object-recognition performance in the present study, whereas they were in the Chua et al. study. Keywords: cross cultural differences; cognitive style; scene processing; eye movements; recognition memory. Introduction There is evidence to suggest that Westerners and East Asians differ markedly in their cognitive processing styles. For example, Westerners attend more to focal objects, whereas East Asians attend more to contextual information. By tracking the eye movements of American and Chinese students when viewing pictures of naturalistic scenes, Chua, Boland, and Nisbett (2005) found that the American students fixated more on the focal object in the scene, whereas the Chinese students fixated more on the background. In a subsequent object-recognition task, the Chinese students were less likely to correctly recognize old objects presented in new scene backgrounds, suggesting that they tended to bind the object with the background. Chua et al. interpreted these findings as evidence that Westerners tend to engage in a processing style that is analytic and object-centered, whereas East Asians tend to engage in a processing style that is holistic and more attentive to context and relationships. The study by Chua et al. (2005) was part of a highly influential and frequently cited research program conducted by Nisbett and his colleagues (e.g., Masuda & Nisbett, 2001; Markus & Kitayama, 1991; Nisbett & Masuda, 2003; Nisbett, Peng, Choi, & Norenzayan, 2001). In addition, the use of eye movement monitoring by Chua et al. (2005) provided particularly strong and direct evidence for cultural differences in the encoding of focal objects and contextual information in natural scenes. Given the theoretical importance and methodological innovation of the Chua et al. (2005) study, the present research attempted to provide an independent replication of their findings. Accordingly, we begin with a brief summary of the prior findings concerning cultural differences in cognitive processing styles followed by a description and discussion of the present results. Cultural differences in cognitive processing styles have emerged on tasks measuring memory and perceptual judgments (Ji, Peng, & Nisbett, 2000; Kitayama, Duffy, Kawamura, & Larsen, 2003; Masuda, & Nisbett, 2001), Stroop interference (Ishii, Reyes, & Kitayama, 2003), and self-descriptions (Kanagawa, Cross, & Markus, 2001). Masuda and Nisbett (2001) investigated the way in which Westerners and East Asians attend to complex visual displays. They had American and Japanese students view animated vignettes of underwater scenes and report the contents of each vignette immediately after viewing it. Then at the end of the experiment, participants were asked to make old/new recognition memory judgments for animals in a new series of pictures, some of which showed an original focal object against its original background, and others of which showed the original focal object against a new background. The immediate recall task showed that Americans and Japanese were equally likely to mention the focal objects (large, brightly colored, rapidly moving objects) in their reports. However, Japanese students reported more information about the background (e.g., rocks, small nonmoving objects, color of water) and the relationships between the focal objects and the background than did the American students. Moreover, Japanese students recognized previously seen objects more accurately when they saw them with their original backgrounds intact than when they saw them with novel backgrounds, whereas this manipulation had no effect on Americans. Masuda and Nisbett (2001) interpreted their findings as evidence for the fact that East Asians are more attentive to context and relationships than are Westerners (p. 932). 2428

2 Although Masuda and Nisbett (2001) attributed their memory findings to cultural differences in attention to context, it is quite possible that their immediate recall and delayed recognition findings were due to differences in retrieval processes or response bias rather than differences in the initial allocation of attentional resources to the perceptual task. To gain more direct evidence concerning attentional strategies during perception and encoding, Chua et al. (2005) monitored the eye movements of American and Chinese students while they engaged in a similar sceneviewing task. During the eye-tracking phase, participants viewed a series of 36 pictures on a computer monitor. Each picture contained a focal object (e.g., a cow) against a complex, naturalistic background (e.g., meadow with trees and a snow-capped mountain); see Figure 1(Top Panel) for a sample picture. Participants were given 3 s to freely look at the picture, and once it was removed, they were asked to verbally say a number between 1 and 7 to indicate the degree to which they liked the picture. For the yes/no object recognition task, they were presented with 72 pictures in one of four conditions: old object on old background (see top panel of Figure 1); old object on new background (see bottom panel of Figure 1); new object on old background; and new object on new background. Their task was to judge whether or not they had seen the objects in the original scene-viewing phase. background, and the bottom panel depicts the original object on a new background. The recognition memory results were consistent with those of Masuda and Nisbett (2001) in that American participants object recognition performance appeared unaffected by the manipulation of the background context whereas Chinese participants recognized previously seen objects more accurately when they saw them with their original backgrounds intact than when they saw them with novel backgrounds. Like Masuda and Nisbett, Chua et al. (2005) took the memory findings as evidence that East Asians tend to bind object with background. The eye movement findings were consistent with the view that East Asians and Westerners differ in their relative attentiveness to focal object versus context. American participants fixated on the focal object sooner and longer than did their Chinese counterparts, whereas Chinese participants spent longer fixating the background than did the Americans. Chua et al. took these findings as evidence that cultural differences in judgment and memory can be attributed to differences in what is actually attended to as people view scenes. The present study attempted a replication of the Chua et al. study on a group of young adult students of European-Canadian and Chinese heritage. Method Participants There were 51 participants in this study belonging to the following two groups: (1) Twenty-six Chinese students (16 males, 10 females) at the University of Toronto. Their ages ranged from 19 to 32 years (M = years, SD = 3.29), and their mean years of education was years (SD = 2.30). They were all born and raised in China, and had been in Canada for less than 4 years (M = 1.27); (2) Twenty-five European Canadian students (11 males and 14 females) at the University of Toronto. Their ages ranged from 18 to 26 years (M = 20.88, SD = 2.186), and their mean years of education was years (SD= 1.76). All participants had normal or corrected-to-normal vision. Participants were tested individually in a single session lasting approximately 1 hour, and they were paid $ 10 per hour for their participation. The session consisted of two phases: (a) a study phase during which participants viewed 36 pictures while their eye movements were monitored, (b) an object-recognition phase during which participants were given 72 pictures and asked to judge which of them depicted the same objects that had appeared during the picture viewing phase. Figure 1: Sample pictures presented in Chua et al. (2005) study. The top panel depicts the object on its original Study Phase Materials The study materials consisted of the 36 pictures used by Chua et al. (2005). Chua et al. obtained their pictures from the COREL image collection (Corel, Eden 2429

3 Prarie, MN). Using Adobe Photoshop Software, they manipulated the images to create 36 pictures, each with a single, focal, foreground object (living or nonliving) against a realistic complex background. (See Figure 1 for a sample picture and Chua et al., 2005, for more details). Procedure Participants were instructed that they would be viewing a series of pictures on the computer screen, one at a time. Before each picture was presented, there would be a blue screen with a cross sign (+) in the centre of it. Participants were required to look at the cross sign to initiate the picture presentation. Once the picture appeared on the screen, they were free to move their eyes to look at the picture. They were told that after a few seconds, the picture would disappear, and be replaced by a gray screen. At this time, their task was to orally say a number between 1 and 7, indicating the degree to which they liked the picture (1 = don t like at all; 4 = neutral; 7 = like very much). Then, when ready for the next picture, they were to press the space bar, and the next blue screen with cross sign would appear. One sample picture was presented before the experiment began to make sure that participants understood the procedure. After that, the actual task of viewing and rating the 36 pictures began. Each picture was displayed on the screen for 3 s. While participants were viewing the pictures, their eye movements were recorded using an Eyelink 1000 system (SR Research Ltd., Mississauga, Canada). The participant used a chinrest with a head support to minimize head movement. The distance of the chinrest from the monitor was 55 cm. The sampling rate was set to 1000 Hz (1-msec temporal resolution). In the present study, the configurable acceleration and velocity thresholds were set to detect saccades of 0.5º or greater. Only the participant 's dominant eye was tracked in our study. We used two computer monitors for this scene perception task. One was used to display the instructions and pictures to the participants, and the other one was used to display real-time feedback about the gaze position. Eye-tracking calibration was obtained at the beginning of the experiment, and recalibration was conducted during the experiment if needed. After the study phase, participants were moved to another room to do an arithmetic distractor task for 10 minutes. Object-Recognition Phase Materials For the object-recognition task, the original 36 objects and backgrounds used in the study phase, together with 36 new objects and backgrounds were manipulated to create a set of 72 pictures of the following composition: (a) 18 pictures with old (previously seen) objects and the original old backgrounds (old object/old background); (b) 18 pictures of old objects with new backgrounds (old object/new background); 18 pictures of new objects with old backgrounds (new object/old background); and 18 pictures of new objects with new backgrounds (new object/new background). All of the new combinations of objects and backgrounds were quite natural and reasonable. All participants saw the same set and sequence of trials (see Chua et al., 2005 for details). Procedure Participants were brought back to the same computer room to complete the object-recognition task. They were told that they would be viewing pictures again. However, this time their task was to judge whether they had seen the object before, that is, whether the particular animal, car, train, boat etc was exactly the same as the one seen during the study phase. Participants were instructed to press a key labeled YES if they recognized seeing the object before, and a key labeled NO if they thought the object was new. If they were not sure, they were told that they could make a guess. Participants were informed that each picture would only be shown for a brief period. They were encouraged to make their response as quickly as possible, but they were still allowed to respond even after the picture had been removed. To make sure that participants understood the instructions, two sample pictures were shown before the experiment started. Once participants demonstrated that they understood the task, the real task began. The 72 pictures, 36 with the original objects and 36 with new objects, were presented one at a time for 3 s each. After the participant provided a response, the next picture would appear. Eye Movement Data Results and Discussion The main dependent measure of interest was the proportion of dwell time spent fixating the focal object. For each trial we divided the total time spent fixating the focal object by the total dwell time on the object and the background. In addition, in order to look for changes in the time on object across the 3-second time course of a trial, we computed the proportion on object separately for each of 6 consecutive 500 milliseconds bins (see Figure 2A). The two other dependent measures used were number of fixations on the object and the background (see Figure 2B), and average fixation time on the object and the background (see Figure 2C). Figure 2 provides mean performance on these dependent measures as a function of cultural group (Chinese, Western). Our first goal was to determine whether we replicated Chua et al. s (2005) findings of a cultural difference in eyemovement patterns for our participants of Chinese versus Western heritage. As Figure 2A shows, Western participants spent 66% of trial time dwelling on the focal object and this was significantly longer than the 59% of trial time that Chinese participants spent fixating the focal object, t(49) = 2.71, p <.01. In addition, with the exception of the first time bin (corresponding to the first 500 millisecond in the trial) this difference between groups in the proportion of time on object is apparent throughout the remainder of the 3-second time course of a trial. The two groups did not differ in the number of fixations they made on objects, t(49) = 1.20, p >.23, but the Chinese students made significantly more 2430

4 fixations on the background than did their Western counterparts, t(49) = 2.41, p <.03 (see Figure 2B). And finally, for Western students, the average fixation duration to objects was greater than the average fixation duration to backgrounds, t(24) = 3.64, p <.002 (see Figure 2C). In contrast, Chinese students did not show longer fixation durations on objects than on backgrounds, t(25) = 1.08, p >.28 (see Figure 2C). Together, these data were consistent with Chua et al. s finding that Westerners tend to pay more attention to the focal object than do East Asians, whereas East Asians tend to focus on the background context more so than do Westerners. Panel (C) shows average fixation time on the object and the background (in ms). Object-Recognition Data Figure 3 presents the object-recognition data as a function of background (old, vs. new), and culture (Chinese vs. Western). Whereas Chua et al. reported only the hit rates, our data are expressed in terms of hits minus false alarms to control for potential differences in response bias. Again, the primary goal was to determine whether we replicated Chua et al. s (2005) finding that Chinese participants object recognition performance is more accurate when the object is presented in its original background than when it is presented in a novel background, whereas Westerners object recognition performance is unaffected by the manipulation of background context. As Figure 3 clearly shows, we did not replicate the effect. Like Chua et al., we found that Chinese students recognition performance was significantly better when the object was presented on an original background (M =.40) than on a new background (M =.25), t(25) = 4.30, p <.002, a finding that Chua et al. interpreted as evidence that East Asians bind object with context. However, unlike Chua et al., we found that maintaining the original background had an equally facilitative effect on Westerners recognition performance as it did on the Chinese participants. As Figure 3 shows, Westerners were significantly better at recognizing objects when presented on old backgrounds (M =.55) than on new backgrounds (M =.21), t(24) = 5.55, p <.01. These findings were confirmed in an analysis of variance (ANOVA) which showed a highly significant effect of background type, F(1, 49) = 49.52, MSE =.02, p <.01, but no effect of culture (F < 1), and no background type by culture interaction, F(1, 49) = 2.34, MSE =.02, p <.12. Thus, even though our Westerners appeared to be paying less attention to the background when encoding the scenes than did their Chinese counterparts, their recognition performance suggested that they were binding object with the background to the same extent. Figure 2: Eye-movement data as a function of cultural group. Panel (A) shows proportion of dwell time on the object. We computed the numbers separately for each of 6 consecutive 500 milliseconds bins: 0-500ms, ms, ms, ms, ms, ms, represented by 1-6 respectively. We also computed the overall proportion of dwell time on the object by averaging the data across the 3-s time course. Panel (B) shows the mean number of fixations on the object and the background; Hit - false alarms Old background Chinese Westerners New background Figure 3: Hits minus false alarms on the object-recognition task as a function of background (old vs. new) and culture (Chinese vs. Western). 2431

5 Summary and Conclusions Recent claims have been made that East Asians and Westerners perceive the world and think about it in very different ways. Because of cultural norms that emphasize relationships and group functions, East Asians develop a bias toward paying attention to context, and encoding stimuli in a holistic fashion. In contrast, the individualistic society of Westerners produces a bias toward paying more attention to focal objects, and processing them more analytically. Behavioral evidence for differences in cognitive processing styles has come from a variety of paradigms including tasks measuring memory and perceptual judgments (Ji, Peng, & Nisbett, 2000; Kitayama, Duffy, Kawamura, & Larsen, 2003; Masuda, & Nisbett, 2001), Stroop interference (Ishii, Reyes, & Kitayama, 2003), and self-descriptions (Kanagawa, Cross, & Markus, 2001). In particular, by introducing eye movements monitoring methodology, Chua et al. (2005) provided convincing and direct evidence for a cultural difference in the encoding of objects and their background during natural scene processing. Here we provided a replication of this encoding difference. However, these cultural biases in viewing patterns did not appear to be related to later objectrecognition performance in the present study, whereas they were in the Chua et al. study. Given that we used materials, design and procedures that were closely patterned to be as similar as possible to the study by Chua et al. (2005), the difference in results across studies is puzzling. It remains for future studies to determine the conditions in which documented cultural encoding differences influence subsequent memory performance. References Chua, H. F., Boland, J. E., & Nisbett, R. E. (2005). Cultural variation in eye movements during scene perception. Proceedings of the National Academy of Science, 102 (35), Ishii, K., Reyes, J.A., & Kitayama, S. (2003). Spontaneous attention to word content versus emotional tone: Differences among three cultures. Psychological Science, 14, Ji, L.J., Peng, K., & Nisbett, R.E. (2000). Culture, control, and perception of relationship in the environment. Journal of Personality and Social Psychology, 78, Kanagawa, C., Cross, S. E., & Markus, H. R. (2001). "Who am I?" The cultural psychology of the conceptual self. Personality and Social Psychology Bulletin, 27(1), Kitayama, S., Duffy, S., Kawamura, T., & Larsen, J. T. (2003). Perceiving an object and its context in different cultures: A cultural look at new look. Psychological Science, 14 (3), Markus, H.R., & Kitayama, S. (1991). Culture and the self: Implications for cognition, emotion, and motivation. Psychological Review, 20, Masuda, T., & Nisbett, R. E. (2001).Attending holistically versus analytically: Comparing the context sensitivity of Japanese and Americans. Journal of Personality and Social Psychology, 81 (5), Nisbett, R. E., & Masuda, T. (2003). Culture and point of view. Proceedings of the National Academy of Sciences, 100 (19), Nisbett, R.E., Peng, K., Choi, I., & Norenzayan, A. (2001). Culture and systems of thought: Holistic vs. analytic cognition. Psychological Review, 108,