PDA

View Full Version : (Child) Abuse a Pattern of Experience


abdulhakeem
29-06-05, 11:34 PM
By Randy Dotinga
HealthDay Reporter

WEDNESDAY, June 29 (HealthDay News) -- What turns a mother into a child abuser?

The answer in humans remains unclear, but new research with monkeys suggests it may have more to do with experience than genetics.

More than half of female rhesus macaque monkeys who were abused during the first month of life became abusive mothers themselves, whether they were raised by their biological or foster mothers.

"This strongly suggests that it [child abuse] is an issue of early experience," said study author Dario Maestripieri, an associate professor of comparative human development at the University of Chicago. "We can't just blame bad genes."

The study findings appear in the July 5 online issue of the Proceedings of the National Academy of Sciences.

Just like humans, monkeys are no strangers to child abuse. Maestripieri has found that about 5 percent to 10 percent of female monkeys abuse their offspring. Among other things, the mothers drag, step on, bite and pin down their infants, he said.

"At some point, they just treat them like objects," Maestripieri said, adding that occasionally, the monkeys even kill their babies.

"The mothers who are abusive tend to be very consistent. Every year, they have a new infant and repeat the abuse," he said.

If you're wondering about male monkeys, they're not part of the picture: they're absentee fathers, uninvolved in child-rearing.

In the new study, Maestripieri designed an experiment to determine if the female monkeys learned abusive behavior from their own mothers. Researchers at the Yerkes National Primate Research Center in Georgia took monkey infants away from their biological mothers and gave them to foster mothers to see how they developed.

Foster monkey mothers tend to accept new babies under special circumstances, Maestripieri said. "An infant has to be taken away from its mother as quickly as possible after birth, within 24 to 48 hours. And the mother has to be given another infant of the same age and sex," he said.

Nine of 16 monkeys who were abused as babies went on to become abusers themselves, regardless of whether they were raised by their natural or foster mothers. However, another 16 who were raised by non-abusive mothers didn't become abusers, even if their biological mothers were abusive.

This research might offer insights into causes of child abuse in humans, Maestripieri said.

However, Joan Kaufman, a child abuse specialist and assistant professor of psychiatry at Yale University, said the picture produced by the monkey research isn't entirely clear. Since about half of the abused monkeys didn't go on to abuse their own children, factors other than childhood experience must be at play, Kaufman said. She thinks genetics play a major role.

On the bright side, the research does add to the evidence that abused children don't always become abusive parents, Kaufman said. In humans, only an estimated 20 percent to 30 percent do.

"It's not inevitable," she said, "and that's what's important."

More information

Learn more about child abuse from the U.S. Department of Health & Human Services (http://nccanch.acf.hhs.gov/topics/overview/index.cfm).

http://www.forbes.com/lifestyle/health/feeds/hscout/2005/06/29/hscout526556.html

abdulhakeem
29-06-05, 11:37 PM
Infant abuse linked to early experience, not genetics


28 Jun 2005

Intergenerational transmission of infant abuse is more likely caused by early experience than genetic inheritance, new University of Chicago research on macaque monkeys shows.

"Maternal abuse of offspring in macaque monkeys shares some similarities with child maltreatment in humans, including its transmission across generations," said Dario Maestripieri, Associate Professor in the Department of Comparative Human Development at the University of Chicago.

"The mechanisms underlying the intergenerational transmission of abuse are not well understood," said Maestripieri, who is also an affiliate scientist at the Yerkes National Primate Research Center of Emory University. " Ours is the first study to show that rhesus monkey females who are abused by their mothers in infancy tend to become abusive mothers themselves, and the first to provide experimental evidence that the intergenerational transmission of abuse is the result of early experience and not genetic inheritance," he said.

Maestripieri reports his findings in an article, "Early Experience Affects the Intergenerational Transmission of Infant Abuse in Rhesus Monkeys," published in the online Early Edition of The Proceedings of the National Academy of Sciences USA the week of June 27-July 1.

Among macaque monkeys, most of the abuse occurs in the first six months of an infant's life, and most of that abuse occurs during the first month. The abuse consists of such behavior as biting, dragging or hitting.

Maestripieri and his research team cross-fostered female infants between abusive and non-abusive mothers and followed these infants, along with others who were reared by their biological mothers until they gave birth.

Nine of the 16 females who were abused in infancy by their biological or foster mothers were abusive toward their own offspring, while none of the 15 females reared by non-abusive mothers were abusive toward their offspring.

In particular, the researchers found that none of the offspring who were born to abusive mothers but raised by non-abusive foster mothers developed abusive parenting patterns, suggesting that genetic factors do not play a primary role in the intergenerational transmission of abuse.

The research may provide insights into how child abuse is transmitted in human families, Maestripieri said. Researchers estimate that as many 70 percent of the people who abuse their children were abused themselves growing up, Maestripieri added.

"In humans, we aren't ruling out genetics entirely, as some temperamental characteristics, such as impulsivity, may be inherited and have an impact on a parent's potential to abuse children," he said. "What would be interesting to study would be the situations in which infants are abused but do not go on to become abusive parents.

"In monkeys, as in humans, support from social networks may buffer individuals against the negative consequences of early abuse, making them more resilient and less likely to become abusive adults," he said.

William Harms
w-harms@uchicago.edu
773-702-8356
Steve Koppes (from June 23-July 1)
skoppes@uchicago.edu
773-702-8366

University of Chicago
http://www.uchicago.edu (http://www.uchicago.edu)

http://www.medicalnewstoday.com/medicalnews.php?newsid=26716#

abdulhakeem
29-06-05, 11:38 PM
Monkey See, Monkey Abuse

2005-06-28
CATHY TRAN

Children from abusive families are more likely to grow up to be abusive parents, but whether that's due to genetics or environmental influences has remained a mystery. Now, research in rhesus macaques suggests that abusive behavior is driven by early environment. If such findings apply to humans, early behavioral intervention may prove key to breaking the cycle of child abuse.

Research into how abusive behavior passes from one generation to the next has been inconclusive. One study in young boys followed through adulthood found a gene variant linked to disorder and aggression. But another in rats showed that pups frequently licked by their mothers grew up to be more nurturing to their own infants, even if the pups were not raised by their biological parents.

Dario Maestripieri, a behavioral biologist at the University of Chicago, wondered if a more straightforward study could be done on a close relative of humans. While rummaging through the records at the Yerkes National Primate Research Center in Atlanta, Georgia, Maestripieri noticed that, like humans, rhesus macaques abused as infants were likely to become abusive parents themselves--tossing, crushing, and biting their infants. To untangle the issue of whether the pattern he observed was environmentally or genetically based, Maestripieri housed 14 female infants with adoptive abusive or non-abusive mothers.

Maestripieri followed the infants for five years and compared their behavior to that of monkeys raised by their biological mothers. He found that nine out of 16 infants raised by abusive mothers grew up to be abusive mothers themselves. However, none of the infants paired with 15 non-abusive mothers became abusive, regardless of whether they were raised by biological or adoptive mothers. "I was surprised how strong the evidence was in favor of experience [over genetics]," says Maestripieri, who publishes his findings online this week in the Proceedings of the National Academy of Sciences.

"This finding is particularly impressive because the species is close to humans," says Daphne Bugental, a psychologist at the University of California, Santa Barbara. Still, the study doesn't entirely rule out genetics, says Joseph McClay, a geneticist at the Virginia Institute for Psychiatric and Behavioral Genetics in Richmond. Some individuals may be genetically predisposed to become abusive, he says, and this may be exacerbated by early environmental influences.

Related sites

Yerkes National Primate Research Center (http://www.yerkes.emory.edu/)
Dario Maestripieri Behavioral Biology Laboratory (http://primate.uchicago.edu/dario.htm)

http://bric.postech.ac.kr/biotrend/science/science_view.php?nNum=101910