Differential activation patterns in the same brain region led to opposite emotional states

In human studies, how averaged activation in a brain region relates to human behavior has been extensively investigated. This approach has led to the finding that positive and negative facial preferences are represented by different brain regions. However, using a multi-voxel pattern induction method we found that different patterns of neural activations within the cingulate cortex (CC) play roles in representing opposite emotional states. In the present study, while neutrally-preferred faces were presented, activation patterns in the CC that corresponded to higher (or lower) preference were repeatedly induced by the pattern induction method. As a result, previously neutrally-preferred faces became more (or less) preferred. We conclude that a different activation pattern in the CC, rather than averaged activation in a different area, represents and causally determines positive or negative facial preference. This new approach may reveal importance in an activation pattern within a brain region in many cognitive functions.