Fifty Degrees Below by Kim Stanley Robinson

"From the nose to the brain." Oh, my: there were synapses that ran from one end of the brain to the other. They went from the nose to everywhere. Scent, memory, behaviors associated with pleasure. These tapped into the dopamine that was made available in the nucleus accumbens in the basal forebrain, behind the back of the mouth. This availability depended on a long biochemical sequence functioning well at every point.

The right frontal cortices were more associated with negative emotions than the left; the right somatosensory cortices were active in integrating body movement, which might be why they were the apparent seat of empathy. Blocking oxytocin in a female prairie vole did not interfere with its sex drive, but with the attachment to its partner that would usually correlate to sex. Suppressing vasopressin had the same effect on male voles, who would normally be faithful for life, voles being monogamous. You needed both the insula and the anterior cingulate working well to be able to experience joy. Fluency of ideation increased with joy, decreased with sorrow. The brain was often flooded with endogenous opoid peptides such as endomorphines, enkephalin, dynorphin, endorphins -- all painkillers. You needed those. Brain systems that supported ethical behaviors were probably not dedicated to ethics exclusively, but rather also to biological regulation, memory, decision-making, and creativity. In other words, to everything. You needed joy to function well. In fact, it appeared that competent, successful decision-making depended on full capacity in all the emotions; and these in turn depended on a healthy prefrontal cortex.

p. 300

"Fluency of ideation increased with joy" -- I am thinking of the structured decision making processes that we have been working with in the NEAD project and groups such as the Institute for 21st Century Agoras. They begin with a meal so that all the participants see each other as people, not labels or groups. But it also creates satiation and hence joy - and thus ideation. It all fits.