New research from Emory University scientists finds that fathers may play favorites when it comes to their children.

» RELATED: Dad's heart-stopping images of his daughter in 'dangerous situations' go viral

The study, published in the American Psychological Association's journal "Behavioral Neuroscience" last week, examined the influence of fathers' brain responses to male or female children.

Researchers from Emory University and the University of Arizona gathered data from 52 fathers of toddlers (30 daughters, 22 sons) in the Atlanta area for the study.

The fathers wore small computers on their belts for one weekday and one day on the weekend. The gadget recorded any sounds in 50-second intervals every nine minutes during the 48-hour period as well as nighttime interactions in the child’s room, where the device was left charging.

The men also underwent MRI brain scans as they viewed photos of unknown adults, unknown children and their own child with neutral, happy and sad facial expressions.

Here’s what the researchers found:

A father and daughter walk in the city center on July 17, 2012 in Berlin, Germany.

Credit: Sean Gallup

icon to expand image

Credit: Sean Gallup

  • Dads with daughters had greater responses to daughters' happy facial expressions.
  • Dads with sons had greater responses to sons' neutral facial expressions.
  • Dads with daughters spent about 60 percent more time responding to their children than dads with sons.
  • Dads with sons spent three times as long playing with their children.
  • Dads with daughters used more language referencing the child's body, such as "belly," "foot" and "tummy."
  • Dads with sons were more likely to use words such as "win," "proud," and "best."

“The fact that fathers may actually be less attentive to the emotional needs of boys, perhaps despite their best intentions, is important to recognize,” lead researcher Jennifer Mascaro said.

» RELATED: 7 ways parenting has changed in the past 25 years

In addition, regarding the finding that dads with daughters tend to use more body-related words, researchers noted that previous research has shown pre-adolescent girls are more likely than boys to report low self-esteem and body image issues.

But some scientists, including Alan Kazdin, child psychiatry professor and director of Yale Parenting Center, warned against jumping to any conclusions in the small sample study.

"Daughters and sons are very different even in utero and then when they're infants they start behaving very differently," Kazdin told CBS News. "Interactions between parents and children drive and influence each other's brains. So what we don't know here is whether the fathers drive the behaviors of their daughters and the sons or if the daughters and the sons drive the behavior of the fathers."

» RELATED: Father meets daughter for first time after 50 years

In addition, because the research was conducted in the U.S., cultures with varying societal norms are not as well represented.

But knowing there may be unintentional biases in the treatment of children based on gender could help future researchers explore the subject and possibly help fathers identify their biases, Kazdin said.

Read the full study.