Acute social isolation evokes midbrain craving responses like

All the lonely people - Overton

Oxytocin neurons mediate the effect of social isolation via the VTA circuits

Hungry lonely brains - Mapping Ignorance

What Does Loneliness Do to the Brain?

Chronic pain patients low in social connectedness report higher pain and need deeper pressure for pain relief.

The Evolution of Social Connection as a Basic Human Need — Social Creatures

It's Time to Embrace a Better Model of Brain Function: Neural Functioning Owes to Overlapping Areas of Activity, not Isolated Regions - ICJS - International Collegiate Journal of Science

The neural circuitry of social homeostasis: Consequences of acute versus chronic social isolation - ScienceDirect

Social Isolation Provokes Brain Activity Similar to That Seen During Hunger Cravings - Neuroscience News