Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Study Contradicts Conventional Wisdom that Perceptual Abilities Improve as We Grow

25.06.2009
A study of Spanish- and English- learning infants provides evidence that our perceptual abilities do not improve as we get older, and that younger infants may actually be better at integrating facial speech gestures and vocalizations than older infants. The developmental decline in this ability may be due to increasing specialization for native-language phonology as infants learn their own speech and language.

Conventional wisdom says that human perceptual and cognitive functions broaden and improve as humans grow and mature, but a study published in the June 17 issue of the Proceedings of the National Academy of Sciences provides evidence that the opposite occurs in infant perception of audiovisual speech.

Researchers from the Charles E. Schmidt College of Science at Florida Atlantic University and the Universities of Barcelona and Pompeu Fabra in Spain studied English-learning infants in the United States and Spanish-learning infants in Spain to determine if they can perceive people’s facial speech gestures and accompanying vocalizations as part of the same event.

The ability do this is crucial for adaptive communication. Dr. David J. Lewkowicz, professor of psychology in FAU’s College of Science and head of the Infant Development Laboratory, and his colleagues, Drs. Ferran Pons, Salvador Soto-Faraco and Núria Sebastián-Gallés from Spain, hypothesized that younger infants may actually be better at integrating facial speech gestures and vocalizations than older infants and that the developmental decline in this ability may be due to increasing specialization for native-language phonology as infants learn their own speech and language.

“Our hypothesis is contrary to conventional wisdom because it assumes that perceptual abilities improve as infants develop,” said Lewkowicz. “Consistent with our hypothesis, we found that younger infants could integrate the facial and vocal gestures of foreign speech sounds, but that older infants no longer did.”

The results of this study provide the first evidence that perception of audiovisual non-native speech narrows during infancy precisely during the time that infants are acquiring their native language phonological system. These researchers demonstrate that the perceptual system becomes gradually tuned to key native-language audio-visual correspondence, and as it does so, sensitivity to the phonetic information inherent in foreign language sounds declines.

To investigate their hypothesis, the researchers presented infants with speech syllables (/ba/ and /va/) that are distinguishable to English speakers but not to Spanish speakers. During the experiment, infants first watched side-by-side videos of the same person silently and repeatedly uttering a /ba/ syllable on one computer monitor and a /va/ syllable on the other monitor. Results of this test showed that the infants did not prefer one syllable over the other. Then, the researchers allowed the infants to listen to either the /ba/ or the /va/ syllable for 45 seconds and then tested their preferences for the visual syllables again by showing the silent versions of the side-by-side syllables. This time, the six-month-old Spanish infants showed a clear preference for the visible syllable that matched the audible syllable that they had just heard, indicating that they perceived them as belonging together. In contrast, the 11-month-old Spanish infants did not show such a preference indicating that they did not perceive the audible and visible syllables as belonging together. This latter finding was consistent with the fact that the /v/ sound does not exist in Spanish and with the idea that the older Spanish-learning infants’ greater experience with the Spanish language reduced their sensitivity to the visible and audible sounds of other languages.

Unlike the decline in the ability to integrate auditory and visual speech in Spanish-learning infants, the researchers found that both six-month-old and 11-month-old English-learning infants successfully matched the audible and visible syllables. In addition, the researchers confirmed that the decline in the perception of non-native audiovisual speech persists into adulthood by showing that Spanish adults were unable to integrate the same syllables that were presented to the infants, but that English adults easily did.

“It is important to emphasize that the perceptual narrowing that we found does not reflect a complete loss of perceptual sensitivity to non-native sensory inputs,” said Lewkowicz. “Rather, it reflects a reorganization of perceptual mechanisms that then leads to decreased sensitivity to non-native sensory inputs.”

Florida Atlantic University opened its doors in 1964 as the fifth public university in Florida. Today, the University serves more than 26,000 undergraduate and graduate students on seven campuses strategically located along 150 miles of Florida's southeastern coastline. Building on its rich tradition as a teaching university, with a world-class faculty, FAU hosts ten colleges: College of Architecture, Urban & Public Affairs, Dorothy F. Schmidt College of Arts & Letters, the Charles E. Schmidt College of Biomedical Science, the Barry Kaye College of Business, the College of Education, the College of Engineering & Computer Science, the Harriet L. Wilkes Honors College, the Graduate College, the Christine E. Lynn College of Nursing and the Charles E. Schmidt College of Science.

Gisele Galoustian | Newswise Science News
Further information:
http://www.fau.edu

More articles from Studies and Analyses:

nachricht Drone vs. truck deliveries: Which create less carbon pollution?
31.05.2017 | University of Washington

nachricht New study: How does Europe become a leading player for software and IT services?
03.04.2017 | Fraunhofer-Institut für System- und Innovationsforschung (ISI)

All articles from Studies and Analyses >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Can we see monkeys from space? Emerging technologies to map biodiversity

An international team of scientists has proposed a new multi-disciplinary approach in which an array of new technologies will allow us to map biodiversity and the risks that wildlife is facing at the scale of whole landscapes. The findings are published in Nature Ecology and Evolution. This international research is led by the Kunming Institute of Zoology from China, University of East Anglia, University of Leicester and the Leibniz Institute for Zoo and Wildlife Research.

Using a combination of satellite and ground data, the team proposes that it is now possible to map biodiversity with an accuracy that has not been previously...

Im Focus: Climate satellite: Tracking methane with robust laser technology

Heatwaves in the Arctic, longer periods of vegetation in Europe, severe floods in West Africa – starting in 2021, scientists want to explore the emissions of the greenhouse gas methane with the German-French satellite MERLIN. This is made possible by a new robust laser system of the Fraunhofer Institute for Laser Technology ILT in Aachen, which achieves unprecedented measurement accuracy.

Methane is primarily the result of the decomposition of organic matter. The gas has a 25 times greater warming potential than carbon dioxide, but is not as...

Im Focus: How protons move through a fuel cell

Hydrogen is regarded as the energy source of the future: It is produced with solar power and can be used to generate heat and electricity in fuel cells. Empa researchers have now succeeded in decoding the movement of hydrogen ions in crystals – a key step towards more efficient energy conversion in the hydrogen industry of tomorrow.

As charge carriers, electrons and ions play the leading role in electrochemical energy storage devices and converters such as batteries and fuel cells. Proton...

Im Focus: A unique data centre for cosmological simulations

Scientists from the Excellence Cluster Universe at the Ludwig-Maximilians-Universität Munich have establised "Cosmowebportal", a unique data centre for cosmological simulations located at the Leibniz Supercomputing Centre (LRZ) of the Bavarian Academy of Sciences. The complete results of a series of large hydrodynamical cosmological simulations are available, with data volumes typically exceeding several hundred terabytes. Scientists worldwide can interactively explore these complex simulations via a web interface and directly access the results.

With current telescopes, scientists can observe our Universe’s galaxies and galaxy clusters and their distribution along an invisible cosmic web. From the...

Im Focus: Scientists develop molecular thermometer for contactless measurement using infrared light

Temperature measurements possible even on the smallest scale / Molecular ruby for use in material sciences, biology, and medicine

Chemists at Johannes Gutenberg University Mainz (JGU) in cooperation with researchers of the German Federal Institute for Materials Research and Testing (BAM)...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Plants are networkers

19.06.2017 | Event News

Digital Survival Training for Executives

13.06.2017 | Event News

Global Learning Council Summit 2017

13.06.2017 | Event News

 
Latest News

Collapse of the European ice sheet caused chaos

27.06.2017 | Earth Sciences

NASA sees quick development of Hurricane Dora

27.06.2017 | Earth Sciences

New method to rapidly map the 'social networks' of proteins

27.06.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>