Every thought, memory, emotion, or perception that you construct in your life includes something about the state of your body. Your interoceptive network, which regulates your body budget, is launching these cascades. Every prediction you make, and every categorization your brain completes, is always in relation to the activity of your heart and lungs, your metabolism, your immune function, and the other systems that contribute to your body budget. The whole of our mental lives, Barrett argues, reflects nothing so much as the brain’s busy and deeply anticipatory body-budgeting activity.
