Scientists have found that these particular chemicals are involved in regulating mood, but they are unsure of the exact ways that they work.

科学家发现这些特别的化学物质可以调整心情，但是他们不确定他们作用的具体方式。

youdao

In many people with the condition this is related to difficulties in regulating mood and anxiety.

BBC: Deep brain stimulation 'helps in severe anorexia nervosa'

Antidepressant drugs work by regulating serotonin, which affects mood and sleep.

FORBES: Scientists Find a Brain Wave for Alcoholism