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Autism linked to
By Nathan Seppa
Obese women are more likely to have
children who develop autism than are
normal-weight women, a new study
suggests, adding another possible explanation for the apparent rise in autism.
Reporting in the May Pediatrics,
researchers also found that women who
were obese or had some form of diabetes during pregnancy were more likely
to have kids with developmental delays.
And tests show that a woman’s obesity,
diabetes or high blood pressure during
pregnancy might place her offspring at
risk of slightly impaired learning even if
they don’t have autism.
The new research “underscores the
importance for people who are preg-
nant — or trying to get pregnant — of
controlling their risks,” says epidemiol-
ogist Hannah Gardener of the Univer-
sity of Miami in Florida. “This is a very
of thoughts and behavior and struggles
with language, communication, physical
coordination, social skills and the shar-
ing of emotions.
By Laura Sanders
When it comes to intellectual challenges,
rats, like people, fall naturally into categories of slackers and workers. And a shot
of stimulant sometimes gets slackers to
work harder while prompting the workers to ease off, researchers report online
March 28 in Neuropsychopharmacology.
Animal studies that explore the costs
and benefits of difficult tasks usually
involve rodents physically working,
such as pushing a lever or scaling a wall
for a reward. But such experiments
don’t account for mental effort, says
Jay Hosking of the University of British
Columbia in Vancouver.
or a hard one (the light flashed for a fifth
of a second, so rats had to concentrate to
choose the right hole). The harder task
offered double the sugar-pellet reward.
Some individuals reliably went for the
easy version and collected their small
reward. Other animals overwhelmingly
chose the intellectually harder route. The
differences persisted across many trials.
Giving rats stimulants produced varied effects. For slackers, amphetamine
sharpened the mental work ethic, making the animals more likely to choose the
harder task. But for workers, amphetamine caused the animals to prefer the
easier option. Caffeine turned workers
into slackers but didn’t make slackers