A study released yesterday by a University of New Hampshire professor suggests kids who are spanked have a lower IQ down the road than those who aren't.

The results were more pronounced in younger children: IQs of children ages 2 to 4 who were not spanked were 5 points higher four years later than their un-spanked peers, while the IQs of children ages 5 to 9 years old who were not spanked were 2.8 points higher.

Also linked to spanking? Higher rates of post-traumatic stress symptons like heightened awareness, anxiety and being easily startled.

The more often parents spanked, the more significant the effect, but even occasional spanking - once or twice over the course of childhood - made a difference.

The study notes:

[C]orporal punishment is extremely stressful and can become a chronic stressor for young children, who typically experience corporal punishment three or more times a week...

Twenty-four countries ban the practice - the United States in not one of them - and the use of corporal punishment has been falling in recent decades.

Error parsing XSLT file: \xslt\article-detail.xslt