cohesion exists within a given state of mind as a form of synchronic integration... coherence is created across states of mind as a form of diachronic integration.
Siegel rigorously distinguishes synchronic cohesion within a self-state from the diachronic coherence that emerges across states, establishing integration as the mechanism underlying both forms of situational unity.
, The Developing Mind: How Relationships and the Brain Interact to Shape Who We Are, 2020thesis