Racism is hardwired into the brain and operates unconsciously because areas that detect ethnicity and control emotion are closely connected, according to scientists.

Researchers explain that the same brain circuits that allow us to classify a person into an ethnic group overlap with other circuits that process emotion and make decisions, leading people to make unconscious decisions based on another's race.

The latest study, published in the journal Nature Neuroscience, found that functional magnetic resonance imaging brain scans revealed that interactions between people from different racial groups trigger reactions that researchers think may be completely unknown to our conscious selves.

Researchers led by psychologist and neuroscientist Dr. Elizabeth Phelps of New York University reviewed past brain imaging studies showing how different social categories of race are processed, evaluated and integrated in decision-making.

Past research found that the amygdala, an almond-shaped brain region located deep within the brain that processes fear and emotions, dorsolateral prefrontal cortex involved in top-down emotional control, and the anterior cingulate cortex that manages conflict between intentional and unintentional tendencies, and the fusiform face area that differentiates between familiar and unfamiliar faces, were simultaneously active during tasks that engaged racial bias like having participants view black and white faces while doing different tasks.

Phelps and her team said that not only are these brain areas important in the unintentional, implicit expression of racial attitudes, the functional connectivity that links them together are critical for this processing.

"A few decades ago, it was unthinkable that looking at the brain to understand representations of social groups such as black versus white was even possible, let alone that such explorations could yield useful knowledge," the authors wrote, according to the Daily Mail. "Evidence from neuroscience has been vital in clarifying the nature of how intergroup cognition unfolds."

Researchers said that research into the neuroscience of race will help them reveal individual behaviors of what happens when intergroup cognition is at stake and if it is possible to change real human interactions.

"How to use this knowledge from brain and behavior to further extend basic knowledge and to drive applications is the obvious next generation of questions that we must pose," they wrote. "If good people who intend well act in a manner inconsistent with their own standards of egalitarianism because of the racial groups to which 'the other' belongs, then the question of change takes on new and urgent meaning."

"This urgency requires that we attend to the evidence about how our minds work when we confront racial and other group differences," they concluded. 

"This goes back to potent psychobiological theories of human behavior," said psychiatrist and neuroscientist Anthony Harris, with Sydney University's Medical School, according to The Australian. "But it's very difficult to tease out the cultural influence on our biological processes."

Researchers say that the next step was to develop techniques to reduce or eliminate the negative associations that make up unwanted implicit racial attitudes.