Washington, August 8 (ANI): The increase or decrease in the usage of certain words over the past two hundred years has also affected human psychology, a new study has revealed.

Patricia Greenfield, a distinguished professor of psychology at UCLA and the author of the study, said that the study which analysed more than 1 million books published over 200 years, has revealed how human psychology has evolved in response to major historical shifts.

Greenfield said that for instance, the words “choose” and “get” rose significantly in frequency between 1800 and 2000, while “obliged” and “give” decreased significantly over these two centuries. “Choose” and “get” indicate “the individualism and materialistic values that are adaptive in wealthier urban settings,” while “obliged” and “give” “reflect the social responsibilities that are adaptive in rural settings.”

Usage of “get” declined between 1940 and the 1960s before rising again in the 1970s, perhaps reflecting a decline in self-interest during World War II and the civil rights movement, she noted.

Greenfield also observed a gradual rise in the use of “feel” and a decline in the use of “act,” suggesting a turn toward inner mental life and away from outward behavior. She found a growing focus on the self, with the use of “child,” “unique,” “individual” and “self” all increasing from 1800 to 2000.

Over the two centuries, the importance of obedience to authority, social relationships and religion in everyday life seems to have waned, as reflected in the decline of “obedience,” “authority,” “belong” and “pray.”

Greenfield said that this research showed that there has been a two-century-long historical shift toward individualistic psychological functioning adapted to an urban environment and away from psychological functioning adapted to a rural environment.

She said that the currently discussed rise in individualism is not recent but has been going on for centuries as people moved from a predominantly rural, low-tech society to a predominantly urban, high-tech society.

Greenfield used Google’s Ngram Viewer, a publicly available tool that can count word frequencies in a million books in less than a second and studied a wide variety of books, including novels, non-fiction publications and textbooks.

To assess culture-wide psychological change, Greenfield examined the frequencies of specific words in approximately 1,160,000 books published in the United States.

Drawing on her theory of social change and human development, she hypothesized that the usage of specific words would wax and wane as a reflection of psychological adaptation to sociocultural change. The data supported her hypothesis.

The same patterns in word usage also emerged in approximately 350,000 books published in the United Kingdom over the last 200 years. She was able to replicate all findings using synonyms for each target word in the both the US and UK books.

The study has been published on online edition of the journal Psychological Science. (ANI)