Psychological research has often minimised the differences between cultures and developed theories almost entirely based upon the study of one culture alone. The dominant culture within psychology is the Western, individualist culture, in particular, the United States of America.

Cultural Bias: Refers to the tendency to minimise cultural differences and interpret all phenomena through the 'lens' of ones own culture.

Ethnocentrism: This is when other cultures are judged by the standards and values of one's own culture. In an extreme form, it is the belief that one's culture is superior to another which can lead to prejudice and discrimination towards other cultures.

Cultural relativism: Cultural relativism is the principle of regarding the beliefs, standards, values, and practices of a culture from the viewpoint of that culture itself.

In 1992, 64% of the world's 56,000 psychology researchers were Americans. In Baron's 1991 text book on social psychology, 94% of the studies cited were conducted in North America. This suggests that as well as being a male-dominated discipline, psychology is also the study of white American males. Despite having restricted their enquiries to particular parts of the world, many psychologists have routinely claimed to have discovered universal facts about humans using the evidence from an ethnocentric study.

Cultural bias in the diagnosis of mental disorders. Dsm-5 has a specific section for culture-bound syndromes such as Koro, an obsessive fear of the penis shrinking or nipples inverting in young Asian men and some Asian Women. The fear of this damages the body.

Vygotsky’s work was seen as ethnocentric and was criticised for cultural bias. He worked in a collectivist culture and this potentially affected how he emphasised the role of culture in a cultures influence on a child’s cognitive development. 

The description of addiction in Western cultures is based on the diagnostic  manuals, whereas addiction to substances in particular is evident across cultures. However, for some cultures addiction to opiate derivatives, for example, is not a problem. 

Ainsworth's strange situation is criticised as reflecting only the norms and values of American culture.

Ainsworth identified the key defining variable of attachment type as the child's experience of anxiety on separation. She suggested that 'ideal' (or secure) attachment was characterised by the infant showing moderate amounts of distress when left alone. This leads to misinterpretation of other cultures, for instance German mothers were seen as cold+ distant, and therefore this is an inappropriate measure of attachment.

This was further proved by Takahashi and kronenberg.

Ainsworth's research is one example of an imposed etic in psychology. In assuming that the US-based model of classifying attachment was the norm, Ainsworth imposed her own cultural understanding upon the rest of the world. She studied behaviour within a single culture (America) and then assumed her ideal attachment type could be applied universally.

Imposed etic: An imposed etic approach looks at behaviour from outside of a given culture and attempts to describe those behaviours that are universal.

Emic: An emic approach functions from within or inside certain cultures and identifies behaviours that are specific to that culture.

Brislin (1976) illustrates the concepts of ethnocentrism and imposed etic using the example of intelligence tests. Demonstrations of intelligence in Western culture often involve completing tasks 'against the clock' such as in timed assessments like exams. Brislin questions the validity of this notion of 'mental quickness'. The Baganda people of Uganda characterize intelligence as slow, careful and deliberate thought (Wober 1974). They might view 'speed of thought' as thoughtlessness or rashness.