Your Brain Sees What You Are Missing

An article reporting the results of a study focusing on how the brain works made science news this month, when researchers found that the human brain has the capacity to process and understand things that we see, without being consciously aware of them. The article was printed in the science journal Psychological Science, detailing how the study was performed and why the results are so important. Jay Sanguinetti, a doctoral candidate in the Department of Psychology at the University of Arizona performed the study by showing participants a series of black silhouettes. A select number of these images contained objects within the white spaces in the outer perimeters. The subjects’ brainwaves were monitored with an EEG during the viewing. Their goal was to determine whether the brain was capable of processing the objects that were present on the perimeter of the silhouettes. According to the measurement of the participants’ brainwaves, the person does not have to be consciously aware of the shapes in the image they see for their brain to recognize that they are there, or to understand what they are. Sanguinetti, working with advisor Mary Peterson, a professor of psychology, and others, found that there is a brain signature for meaningful processing called N400. This peak is reached at approximately 400 milliseconds after seeing the image. The fact that the N400 peak is reached indicates that the brain has recognized the shapes in the perimeter. Although the interpretations are made, the brain rejects them, preventing the person from being aware that they are there. Controls were used in the form of images without objects in the perimeter, causing no effect on the brain. As a follow-up to this amazing discovery, Sanguinetti and Peterson plan to continue their research in the future to find the areas of the brain where the processing of meaning occurs. The discovery that the brain processes things in our surroundings that we will never perceive leaves the researchers with more questions about how the brain evolved to perform these processes and how it determines what is important and what is not.