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Discovering Psychology: Updated Edition

Past, Present, and Promise

Past, Present, and Promise is the first program in the Discovering Psychology series. It provides an introduction to and overview of psychology, from its origins in the nineteenth century to current study of the brain's biochemistry. You'll explore the development of psychology in general and some of the paths scientists take to determine relationships among the mind, the brain, and behavior.

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Experiment: Tracking Racial Bias

Psychology is defined as the scientific study of the behavior of individuals and their mental processes. Like many sciences, psychology has evolved with technology, giving doctors and researchers new tools to measure human behavior and analyze its causes.

In this program, Dr. Mahzarin Banaji from Yale University uses the Implicit Association Test (IAT) to measure how quickly positive or negative values are associated with white or black faces. Her subjects are shown a series of words and pictures and instructed to respond immediately by pushing a button to indicate their most automatic, reflex-like reactions. For example, they may be told to press a button in their right hand if the automatic association is good and to press a button in their left hand if the association is bad. The speed with which the subjects respond is an important element of the experiment because these quick, unconscious connections can reveal biases that differ from conscious beliefs.

The IAT results are matched against functional Magnetic Resonance Imaging (fMRI) data to track activity in the amygdala, the region of the brain that responds to fearful or negative images. By correlating data on the buttons subjects pushed with fMRI information about activity in the amygdala, Dr. Banaji and her colleagues have found some interesting results. The majority of the white American respondents showed an unconscious association of white with good and black with bad, while the African American respondents showed mixed results. Half more quickly associated black with good, and the other half associated white with good.

Tracking brain activity in controlled experiments reveals not only the region of the brain at work, but also the power of images and messages in our culture on the subconscious human psyche, bringing psychologists one step closer to understanding human behavior.

Dr. Banaji and her colleagues at Yale have created a Web site with a version of their IAT, which refines and improves previous methods of gathering data. Measure your own implicit attitudes and learn more about IAT research on their website.


Electroencephalogram (EEG): The process of recording the brain’s electrical activity by attaching electrodes to the scalp and analyzing wave patterns.

Nonverbal Communication: Communication between people without the use of words. Examples include tone of voice, body language, and facial expression.

Principles of Psychology, The by William James: A seminal text in the field published in 1890, while James served as a professor at Harvard University. The full text of the work is available here.