NEW YORK - More authority on the job increases symptoms of depression among women, but decreases them among men, according to a new study by US sociologists.

Researchers looked into 1,500 middle-aged women from Wisconsin and compared their workplace experiences with 1,300 men in the same age bracket from the same US state.

They found that women with job authority -- the ability to hire, fire and influence pay -- exhibited significantly more symptoms of depression than those who did not, media reports said.

"In contrast, men with job authority have fewer symptoms of depression than men without such power," researcher Tetyana Pudrovska of the University of Texas at Austin was quoted as saying.

The study, "Gender, Job Authority, and Depression," appears in the December issue of the Journal of Health and Social Behavior.

"What's striking is that women with job authority in our study are advantaged in terms of most characteristics that are strong predictors of positive mental health," Pudrovska said.

"These women have more education, higher incomes, more prestigious occupations, and higher levels of job satisfaction and autonomy than women without job authority. Yet, they have worse mental health than lower-status women."

So why does having job authority increase symptoms of depression in women, but decrease them in men?

"Women in authority positions deal with interpersonal tension, negative social interactions, negative stereotypes, prejudice, social isolation, as well as resistance from subordinates, colleagues and superiors," Pudrovska said. "(They) are viewed as lacking the assertiveness and confidence of strong leaders."

"But when these women display such characteristics, they are judged negatively for being unfeminine. This contributes to chronic stress."

Men, on other hand, do not have to wrestle with the negative stereotypes that haunt women, she said

""Men in positions of authority are consistent with the expected status beliefs, and male leadership is accepted as normative and legitimate," she said. "This increases men's power and effectiveness as leaders and diminishes interpersonal conflict."

The findings indicate "we need to address gender discrimination, hostility and prejudice against women leaders to reduce the psychological costs and increase the psychological rewards of higher-status jobs for women," Pudrovska said.