Abstract
Differing self-construal’s, religious beliefs, moral attitudes and other sociocultural aspects all demonstrate cultural variation. Whether brain and cognition are affected by this disparity is currently a hugely influential topic. Studies demonstrate cognitions such as perception, attention, memory and emotion tend to be shaped by cultural discrepancy, with neuroscience suggesting differing activity in distinctive brain regions underlying these processes. With knowledge acquired through research in this field there are important applications; informing cognitive theory, pharmacological efficacy and better understanding mental health. There are criticisms regarding research methodology and some suggestions for how future studies should overcome these. Overall, the paper argues that culture does shape our brains and cognitive processes.
Key words: culture, cultural neuroscience, cognition.
Culture is defined as the particular customs, ideas and social behaviour of people in a society (Oxford Dictionary, 2017). Without a theoretical and empirical approach fully incorporating cultures role, understanding of the human mind would be impoverished (Chiao, 2009). As neuroimaging technology has begun to proliferate within the past twenty years (Chiao, 2009), cultural study in relation to brain and cognition is undertaken by neuroscience, building on previous behavioural data. Cultural neuroscience examines the posing question of whether cultural variation shapes psychological, neural and genomic processes in individuals (Ortega & Vidal, 2016). This paper provides evidence to support the argument that culture does, shape the human brain and subsequent cognitive processes.
Individualism and collectivism are two primary schemas within cultures explaining how people define themselves and their relation to others (Chiao, Cheon, Pornpattanangkul, Mrazek & Blizinsky, 2013). Self-construal’s are seen as important cultural factors shaping brain function and influencing subsequent cognition, behaviour and emotion (Han & Humphreys, 2016/Lidell, 2017). ‘Individualistic’ (western) cultures are characterised by an independent style, stressing self-focused attention. Whilst ‘collectivist’ (eastern) persons have an interdependent style emphasising interconnection with others (Hans & Northoff, 2008).
Psychologists have started to query assumptions of a universal architecture within individuals, by arguing culture may affect our perceptual and cognitive modes, and ways we process information (Cramer, Dusko & Rensink, 2016).
Research demonstrates self-construal style influences perception and attentional control, finding differences in attentional/perceptual networks in the brain, including parietal and frontal brain areas (Hans & Northoff, 2008). Variation in perception include collectivists greater ability to incorporate contextual information, displaying a wider scope of attention, whilst individualists are better at ignoring this by focusing and attending to more salient objects (Amer, Ngo & Hasher, 2017). Behavioural studies demonstrated this with Japanese (collectivist) participants incorporating contextual information in the perception of focal objects whilst North American (individualist) participants ignored contextual information (Kitayama et al., 2003).
The neural underpinnings of cultural cognitions have been investigated using behavioural measures alongside neuroimaging and electrophysiological techniques. Kitayama and Murata (2013) used event-related potentials (ERP) to investigate whether attention was more focused for European Americans than Asians. ERP’s are electrical potentials generated by the brain, measuring response to specific internal or external events including decisions (Luck, 2012). Images of animals in natural scenes were presented to participants for 68 trials and another 12 replaced the animal with a perceptually distinct stimulus. Subjects were instructed to press the button once they had detected the target: perceptually distinct stimulus. Although there was no significant difference in behavioural performance – neither cultural group differed in accuracy or detection of the target. One waveform the ERP obtained was significantly greater for European Americans than Asian Americans. This positive waveform, SW, has previously been suggested to provide additional processing beyond the normal applied to distinct stimuli (Kitayama & Murata, 2013). Implying European Americans (individualist) are more likely to have more concentrated, focused attention and use prior knowledge to elaborate on objects. Suggesting neural networks attentional cognition is shaped by cultural variation.
Lidell et al., (2015) presented participants incongruent figures, then two congruent composite shapes appeared. Participants were instructed to either select the composite figure corresponding to global features (global condition) or corresponding to local features (local condition) whilst their brain activity was imaged. Results showed individualistic participants showed greater activity within attentional networks when performing global tasks, whilst collectivist participants showed similar activity in attentional and maintenance systems when local processing. Implying greater cognitive resources are used when overcoming interferences that are incongruent with individual’s cultural norm or perceptual and attentional processing. Therefore, arguing that culture shapes brain activity when engaging in cognition processes that are altered by culture.
Goh et al., (2007) demonstrated neural regions show cultural disparity as a function of age. They investigated brain areas involved in object and background processing using functional magnetic resonance imaging (fMRI). Participants from America and Singapore both produced similar adaptation responses in the lateral occipital cortex and para-hippocampal gyrus, both linked to object and background processing. However, stronger adaptation responses in these areas were found in westerners than easterners but only in elderly subjects, suggesting cultural experience modulates brain and cognition as an interaction with age. Goh et al., (2007) suggested this may be because elderly participants have more exposure to their cultural environments than younger subjects. This suggests age but it nonetheless supports the argument that cultural experience modulates perceptual processes in the visual cortex.
Influence of culture on perception has been behaviourally tested in Japanese and American children finding evidence of disparity. Kuwbara and Smith (2016) used pairs of children (one American, one Japanese) to show this. Pairs were allocated to three tasks which tested children’s abilities to recognise objects by their diagnostic features and measure their dependence on spatial information among these. All task categories included animals and artefacts which were identified as common amongst children in both cultures meaning it was equally complex. Differences in perception were shown across all tasks, with Japanese children evidencing recognition more holistically and American children’s recognition being based on individual diagnostic features. Differences persisted despite each task having different demands, showing there is cultural variation in visual processing which begins early in life and ultimately affects how children recognise everyday object categories. It would be interesting to identify whether previously found varying activity and brain regions for visual perception in adults is similar in children to further explore how culture shapes the early developing brain.
Using young children results in questions regarding developmental trajectories. Kuwbara and Smith (2016) identified that although children were on the same developmental trajectory; one group may be more advanced than another with current findings not addressing this.One cultural group could be leading with their perceptual mechanisms and eventually the other cultural group may use these mechanisms. In which case, results may reflect variation in developmental rates induced by culture rather than different systems of object recognition. Despite this, evidence suggests cultural variation does shape perceptual mechanisms at some stage of the early developmental trajectory.
Studying how culture shapes attentional and perceptual networks and subsequent cognition is important as hallmark findings of distinctions are informing cognitive theory (Chiao & Immordino-Yang, 2013). Variation in these cognitions due to culture, also affects how individuals encode and further retrieve information (Chiao, 2009). Millar, Serbun, Vadalia & Gutchess (2013) found that Americans demonstrate greater accuracy on tests of specific memory than East Asians.
Studies now show that for East Asians, previous contextual information is important in subsequent, related tasks (Chaio et al., 2005/Amer, 2017). Amer, Ngo and Hasher (2017) explored this, identifying whether intentional instruction to ignore or focus attention would result in memory of information for further task performance. Participants completed a ‘stroop’ task with instructions to focus only on words colour features. This was followed by a category-generation task testing if participants produced words for categories previously displayed in the ‘stroop’ task. Results showed despite instruction, East Asians showed implicit memory for task-irrelevant words on the category task whilst westerners did not. Suggesting instructions do not eliminate cultural differences seen in attention this shows culture shapes the amount of information encoded and retrieval of this from memory for new tasks. This highlights the importance of examining differences dues to culture beyond immediate task performance. Differences were only noticed in this study, on the subsequent task which implicitly tested participant knowledge. Without this, differences in encoding and retrieval would not have been observed. This has implications for studies relying on immediate task performance, as these studies may have potentially contributed to a bias in publication of research demonstrating cultural cognitive differences (Amer, Ngo & Hasher, 2017). Future studies investigating how cultural variation shapes brain and cognition should measure performance not only on immediate tasks but further tasks, to advance knowledge about differences.
Research further supports these results by examining encoding and memory in East Asians and Americans (Paige, Ksander, Johndro & Gutchess, 2017). Participants viewed objects in a scanner incidentally, encoding them as they were unaware they would have a further recognition rest. East Asians showed increased activation in the left fusiform and hippocampal regions at the time of encoding for same or similar objects presented in the recognition task. Due to unawareness about subsequent recognition test, activation suggests East Asians encode information that may not be contextually meaningful and then use this memory on subsequent tasks. It further suggests East Asians use less efficient processes to perform similarly to Americans on item-specific memory tasks. Findings show not only cultural differences in encoding but also cultural differences in brain activity underlying memory performance.
Culture can also shape perception to emotion with studies finding individuals are better able to recognise emotions expressed by members of their own cultural group (Elfenbein & Ambady, 2002). The amygdala shows increased activation to fear faces expressed by in-group members (Chiao, 2008). Whilst self-construal is important when looking at how culture shapes brain function to influence emotion (Han & Humphreys, 2016/Lidell, 2015), individuals within cultural groups can have varied self-construal (Oyserman et al., 2002) meaning studies rarely look at self-identified construal in relation to emotion.
Lidell et al., (2015) investigated this, allocating participants to conditions respectively based on self-report on the self-construal index. Participants looked at 30 negative and 30 neutral photographs portraying real events reflecting multiple contexts, cultures and genders, whilst brain activity was assessed using fMRI. Participants were instructed to rate negativity of these images and found differences between the neural systems responsive to these social cues. ‘Collectivist’ participants engaged neural regions consistent with context processing when evaluating and showed heightened negative context dependent neural activity in comparison to ‘individualist’ subjects. These findings support the suggestion collectivists depend on contextual cues, which initiate neural responses in sensory and empathic regions to evaluate negative social cues. Individual based self-construal therefore, modulates neural processes used to evaluate negative emotional images, highlighting that variation in self-construal may be significant in regulating neural responses to emotional information. Ultimately, regions of the brain are engaged so subsequent cognitions and behaviours are aligned with their social preferences.
Research into emotion and cultural discrepancy is important to understand culture-bound syndromes. For example, individual with Hwabyung (HB), having feelings of anger due to chronic social aggression (Min, 2009), have shown differing subjective ratings of sad faces and engagement in brain regions in response to these compared to healthy controls (Lee et al., 2009). Such research is important, providing objective measures of mechanisms associated with symptoms of culture-bound diseases that have previously been seen as culturally constructed phenomena (Seligman & Brown, 2010).
Finally, cultural disparity in neural mechanisms of emotion may then adjust risk to psychopathology (Hechtman, Raila, Chiao & Gruber, 2013). This is important as it can affect the response to medical treatments for mental health (Wang et al., 2007) with cultural differences already being identified in the efficacy of pharmacological treatments (Muñoz & Hilgenberg, 2005). This highlights the need for future research to scientifically understand neurobiological bases of emotion (Chiao, 2015). Furthermore, fMRI studies of immigrants would help to understand where and how neural wiring of cognition changes due to cultural influence, but also to identify any culture-specific symptoms of psychiatric disorders and their functional and organisational neural differences. If research found there were culture specific neural abnormalities, this would help influence diagnosis and treatment of psychopathology in across (Hans & Northoff, 2008).
Thus far, the research explained has supported the claim; culture shapes our brain and cognitions. However, there are weaknesses within the cultural neuroscience field that should be identified in order to suggest what future research should focus on and how methodology should be improved. One thing to remember is that although differences in task performance have been shown, the same concepts within cognitive tasks could be interpreted and have distinctive meaning for different cultures (Hans & Northoff, 2008). If true, differing meaning would affect neural activation (Hans & Northoff, 2008) explaining findings of different brain activity recruited for varying cultures. Future research should note this and use tasks that have been established to have similar meanings in both cultures.
Methodological issues lead to queries of homogeneity of cultural groups as there may be country-specific aspects despite being within a broad cultural group (Hans & Northoff, 2009). This is a criticism of how this field has defined culture itself. Culture is an evolving concept which should be redefined as some have (Northoff, 2013) by integrating other factors such as socioeconomic status, unemployment rates to address variation within countries (Ng, Morris & Oishi, 2013). It cannot be disputed that previous research has not accounted for these, and that as cultures differ in more aspects than one, research cannot attribute neural differences found to any one specific aspect of culture (for example, self-construal) (Hans & Northoff, 2008). Furthermore, research has shown that irrespective of cultural association, it is possible that people acquire multiple cultural schemas simultaneously (Chiao et al., 2010).
Studies have overcome this by using psychological-priming procedures to trigger precise cultural knowledge in individuals clarifying what aspect contributes to culture specific neural mechanisms of cognitive processes (Hans & Northoff, 2008). Chiao et al., (2010) for example looked at how priming affects the neural mechanisms in bicultural individuals. They used bicultural Asian American participants and culturally primed them to either an individualistic or collectivist self-concept. The study found that there was a significant interaction between the self-construal prime and the type of self-judgement in participant’s neural responses. They found significantly greater activation for the individualistic prime in the medial prefrontal cortex and posterior cingulate cortex for general descriptions whilst collectivist, showed greater activation for contextual self-descriptions. These two midline structures are thought to underlie self-relevant processes and show that priming to a certain cultural self-construal, can shape our brain and consequent cognitive processes. Despite being psychologically primed, this research shows that culture does shape the human brain and cognitive processes.
One big problem with cultural neuroscience is it can reinforce cultural stereotypes inside laboratories (Choudhury, 2010). As socioecological factors are only now being translated into experimental work, cultural neuroscience still draws conclusions from historical sampling categories such as “Caucasian-American” (Painter, 2010) meaning knowledge is restricted to observation of those living in western industrialised nations (Chiao, 2009). Critics have pointed out that in cultural neuroscience research, participants tend to be classified on their outer appearance rather than their cultural dimensions (Ortega & Vidal, 2016). This is an issue as research has suggested that the notion of “culture” that is used in this discipline functions as a representation of “race” (Heinz et al., 2014).
Future research should incorporate factors that could influence results such as depression and anxiety symptoms on emotional and perceptual mechanisms (Cisler & Koster; Sturhmann, Suslow, & Dannlowski, as cited by Lidell, 2015) or acquisition of more than one cultural schema (Chiao et al., 2010). Perhaps similar approaches to Lidell et al., (2015) assessing depression and anxiety symptoms and using self-report to define culture should be used in the future as these may have been unidentified co-variates in past research.
Having said all this critique no evidence thus far suggests culture to not affect brain and cognition and these are simply things that must be considered to further strengthen this argument. Human brain activity is strongly and in some way shaped by cultural context, with it influencing both high-level cognitions (social cognition) and low-level cognition (perception, attention) (Hans & Northoff, 2008). Behavioural and neuroimaging results have evidenced this and this is important as cultural neuroscience can further inform cognitive theory alongside psychopharmacology. Some limitations have been identified and future research should incorporate these for the field to fully comprehend how diverse cultural environments modulate brain and cognition (Chiao, 2009). Despite these weaknesses, the large body of evidence suggests that culture does shape our brains and cognitions.