Emotions seem personal, and individual, but Cornell researchers have discovered that feelings have a standard code. This cipher provides emotions with a common thread in the human brain that stretches across senses, events, and individuals.
Patterns in brain activity taking place in the orbitofrontal cortex (OFC) seem to act as a code for emotions. That region of the human brain is known to play an important role in emotions.
"If you and I derive similar pleasure from sipping a fine wine or watching the sun set, our results suggest it is because we share similar fine-grained patterns of activity in the orbitofrontal cortex," Adam Anderson of Cornell University said.
Researchers provided a group of volunteers with a series of pictures and tastes. They quizzed subjects about their reactions, and compared the results to brain activity recorded during the experience. In response to stimuli, neurons in the brain appear to create a wide range of codes, covering a spectrum of feelings, between positive and negative.
Pleasant experiences from the eyes and tongue each produced similar patterns in the OFC of subjects. Patterns created by unpleasant experiences also produce patterns similar to each other, regardless of the source. These patterns of neural activity were found to be nearly identical between people.
Neurophysiologists used to believe emotions were registered in brains in regions associated with positive or negative feelings. This new research shows the process of emotions is not as simple as once thought.
"Despite how personal our feelings feel, the evidence suggests our brains use a standard code to speak the same emotional language," Anderson said.
Humans are sometimes said to exhibit six major emotions - happy, sad, excited, angry, tender and scared. Psychologists have recognized several subcategories of these states.
Studies have also shown that people around the world experience the same set of emotions, and express their feelings using nearly-identical facial expressions, regardless of culture. As much as emotions are universal among all people, researchers have long questioned how human brains process feelings within the brain.
The orbitofrontal cortex is located in the frontal lobes of human brains, just behind the eyes. It is critical in the cognitive process of decision-making. The area is highly-networked with neighboring regions of the brain. The region was already known to contain the secondary taste cortex, in which the reward value of taste is represented.
Study of the orbitofrontal cortex and its role in standard coding of emotions was detailed in the journal Nature Neuroscience.