Featured Research

from universities, journals, and other organizations

Mother Mice More Attuned To Pup Sounds Than Others

Date:
June 13, 2007
Source:
Emory University
Summary:
Researchers have shown for the first time that the behavioral context in which communication sounds are heard affects the brain's ability to detect, discriminate and ultimately respond to them. Specifically, the researchers found that the auditory neurons of female mice that had given birth were better at detecting and discriminating vocalizations from mouse pups than the auditory neurons in virgin females.

The researchers found that the auditory neurons of female mice that had given birth were better at detecting and discriminating vocalizations from mouse pups than the auditory neurons in virgin females.
Credit: Robert Liu, PhD / Courtesy of Emory University

Researchers have shown for the first time that the behavioral context in which communication sounds are heard affects the brain's ability to detect, discriminate and ultimately respond to them. Specifically, the researchers found that the auditory neurons of female mice that had given birth were better at detecting and discriminating vocalizations from mouse pups than the auditory neurons in virgin females.

"Although there have been many studies on communication and neurons in animals, such as in primates, birds and bats, those studies have focused on how neurons respond to sounds that were already behaviorally relevant to the animals," says Robert Liu, PhD, Emory University assistant professor of biology and lead author of the study, which appears in the June 12, 2007 issue of PLoS Biology.

"What's different about this study is that we used natural vocalizations -- a range of pup calls -- to see how well neurons in mother mice and virgin, or pup-naοve mice, detect, discriminate and act on this behaviorally important sound," says Dr. Liu. Ultrasonic calls emitted by mouse pups communicate distress and elicit a search and retrieval response from mothers.

"Our current work demonstrates that the neural code for communication sounds in adult mammals can change, either because of experience or because of hormonal mechanisms, as the significance of the signal is acquired. This means that the brain can improve information processing for specific communicative functions," says Liu.

Liu began the work as a postdoctoral fellow in the lab of senior author Christoph Schreiner, PhD, MD, professor and vice chair of otolaryngology, head and neck surgery and a member of the W.M. Keck Foundation Center for Integrative Neuroscience at the University of California, San Francisco.

In the study, the researchers determined that the neurons in the mothers' auditory cortex, an area of the brain that processes sounds, showed larger and earlier electrical spiking, or signaling, than in virgin mice, says Dr. Schreiner.

This shows, says Dr. Liu, that, "the timing plays an important role in the neural code of sounds. The idea that spike timing is important in brain processes has been around for a long time, but we're looking at it specifically in the context of natural communication. And we found that the big difference in encoding is the behavioral relevance of these sounds."

Although the pups' vocalizations vary quite a bit, Dr. Liu says the mothers can still detect the calls, understand them and take action. "What is really intriguing is that behavioral studies have shown that, if you look at vocalizations made by male adult mice, they also make very high-frequency vocalizations as do pups but the mothers don't react to them as they do to the pup calls," says Dr. Liu.

Along these lines, another behavioral study, reported by a team in Germany in 1987, revealed behavioral differences in mice in response to vocalizations. In this case, says Schreiner, there were two groups of mice: "the pup-naive mice and the mother mice who really care about these sounds." The researchers found that, "If you play these vocalizations, the mothers run over to get the pup. If it's a different sound, they don't go as often, and why should they? Likewise, the female mice who have not been mothers don't go to the source of the pup calls more often than to any other vocalization. They're the same age and same species, yet only one thing is different: one group has had pups and the other hasn't. It appears that a switch is thrown that improves sensitivity to these sounds in the mothers."

Dr. Schreiner says further research is needed to determine whether mothers recognize pup sounds immediately after they become pregnant, meaning a hormonal switch has been thrown, or after they give birth. Recognition of pup cries after birth would indicate that exposure to the cries triggers mothers' attentiveness.

Dr. Schreiner likens the improved ability of mother mice to distinguish sounds to what adult humans experience when initially learning a foreign language. "We go to a foreign country, hear what people are saying, but we can't make subtle discriminations of syllables in order to establish the border between words. With time and experience the brain is adjusting to this, our neurons are becoming more discriminative, and we can distinguish words in what initially just appeared to us as an unbroken stream of sound."

According to the authors, this study helps demonstrate how important sounds are encoded in the normal brain but also has implications for developing therapeutic strategies in children and adults who suffer from speech-perception deficits.

This study was supported by a Sloan and Swartz Foundation fellowship, the National Institutes of Health; and the Center for Behavioral Neuroscience under the Science and Technology Program of the National Science Foundation.


Story Source:

The above story is based on materials provided by Emory University. Note: Materials may be edited for content and length.


Cite This Page:

Emory University. "Mother Mice More Attuned To Pup Sounds Than Others." ScienceDaily. ScienceDaily, 13 June 2007. <www.sciencedaily.com/releases/2007/06/070612075243.htm>.
Emory University. (2007, June 13). Mother Mice More Attuned To Pup Sounds Than Others. ScienceDaily. Retrieved September 1, 2014 from www.sciencedaily.com/releases/2007/06/070612075243.htm
Emory University. "Mother Mice More Attuned To Pup Sounds Than Others." ScienceDaily. www.sciencedaily.com/releases/2007/06/070612075243.htm (accessed September 1, 2014).

Share This




More Plants & Animals News

Monday, September 1, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

We've Got Mites Living In Our Faces And So Do You

We've Got Mites Living In Our Faces And So Do You

Newsy (Aug. 30, 2014) — A new study suggests 100 percent of adult humans (those over 18 years of age) have Demodex mites living in their faces. Video provided by Newsy
Powered by NewsLook.com
Washington Wildlife Center Goes Nuts Over Baby Squirrels

Washington Wildlife Center Goes Nuts Over Baby Squirrels

Reuters - US Online Video (Aug. 30, 2014) — An animal rescue in Washington state receives an influx of orphaned squirrels, keeping workers busy as they nurse them back to health. Rough Cut (no reporter narration). Video provided by Reuters
Powered by NewsLook.com
Experimental Ebola Drug ZMapp Cures Lab Monkeys Of Disease

Experimental Ebola Drug ZMapp Cures Lab Monkeys Of Disease

Newsy (Aug. 29, 2014) — In a new study, a promising experimental treatment for Ebola managed to cure a group of infected macaque monkeys. Video provided by Newsy
Powered by NewsLook.com
Killer Amoeba Found in Louisiana Water System

Killer Amoeba Found in Louisiana Water System

AP (Aug. 28, 2014) — State health officials say testing has confirmed the presence of a killer amoeba in a water system serving three St. John the Baptist Parish towns. (Aug. 28) Video provided by AP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
 
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:  

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:  

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile iPhone Android Web
Follow Facebook Twitter Google+
Subscribe RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins