Positive reinforcement is the parenting principle Granada Hills mom Cathy Azaian practices - even when her 5- and 6-year-old require severe correction.
"I pull them aside, and I calmly look at them in their eyes, and I direct them, and I tell them, I say, you need to know the rules," Azaian said.
Rules for punishment may be different for other parents. The new study suggests parents think hard before using any physical form of discipline.
The punishments in question include spanking, hitting and slapping. Study authors say 7 percent of adult disorders can be linked to harsh punishment in childhood. These disorders include depression, mania, anxiety disorders and alcohol and drug abuse.
"If every time you mess up, you do something wrong, the consequence is you're physically being hit, there's always a fear around messing up," said clinical psychologist Sheyda Melkonian.
Melkonian also cites other studies that show spanking leads to children with a lower IQ, and that even mild hand slapping will lead to toddlers less willing to explore their world.
"Spanking is one of those experiences that I feel like once it's done, it changes the parent-child relationship forever because that parent stops being the person that is loving and caring, and it becomes someone that they are afraid of to some degree," Melkonian said.
Many parents still firmly believe spanking is appropriate. While Melkonian does not agree, she says above all, it should never be done in anger because that serves the parent not the child.
"It's to make themselves feel better and to feel like they have control in that situation because they don't know how else to control their child in that situation, and there are a lot of other ways," she said.
When her kids act up, Azaian gives them a time-out to cool off, administers a consequence like taking something away. Then they talk about what happened.
"That'll teach them to grow to become strong, confident individuals," Azaian said.
While Melkonian does not advocate physical punishment, she says experts on the subject say spanking should be done with an open hand and only on a child's bottom.