As in human anxiety disorders, separation anxiety in dogs is caused in part by an imbalance of chemicals in the brain. (neogreyhound.com)
A religion responds to basic human anxieties, such as feelings of guilt. (religion-online.org)
It appears that these tiny little worms have a fear - like response that's very similar to human anxiety when exposed to chemicals given off by its natural predator. (lifeinism.com)