When you listen to someone speaking, it may seem like the words are segmented by pauses, much like the words on this page are separated by spaces. But in reality, you hear a continuous stream of sounds that your brain must organize into meaningful chunks.
One process that mediates this ability is called statistical learning, by which the brain automatically keeps track of how often events, such as sounds, occur together. Now a team of RIKEN scientists has found a signature pattern of brain activity that can predict a person’s degree of achievement in this type of task1.
The team led by Kazuo Okanoya presented volunteers with a 20-minute recording of an artificial language, which they heard passively in three 6.6-minute sessions. While the recording played, participants’ brain activity was measured using an imaging technique called electroencephalograms or EEGs. The researchers then analyzed how the EEG patterns related to events in the recorded language.
This language, instead of being composed of pronounceable syllables, contained only tones, similar to keyboard notes. “We used nonsense tone words to detect basic perceptual processes that are independent of linguistic faculty,” explains team-member Dilshat Abla. This way, the researchers were able to focus on the brain-activity signature of general statistical learning, rather than the specific example of language. The recording heard by the participants consisted of six ‘words’ containing three tones each, but since they were played together without gaps, the word composition would not have been immediately obvious. The participants were told to relax and listen to the streaming sound, and at the end of the experiment, they were tested on which tone triplets came from their recording and which were randomly generated.
The participants succeeded in this discrimination, which revealed to the researchers that they had performed statistical learning without exerting conscious effort. Those who earned average scores in this test showed a distinctive pattern of brain activity in the third recording session. These electric signatures, known as event-related potentials or ERPs, tended to occur 400 milliseconds after the start of a new tone word. Those who scored the lowest did not exhibit these ERPs in any session, suggesting they were not segmenting the start of each word as effectively.
The highest-scoring volunteers did show these ERPs, but only in their first session. Abla explains that the effect is “largest during the discovery phase of the statistical structure,” and represents the process rather than the result of statistical learning.
1. Abla, D., Katahira, K., & Okanoya, K. On-line assessment of statistical learning by event-related potentials. Journal of Cognitive Neuroscience 20, 952–964 (2008).
The corresponding author for this highlight is based at the RIKEN Laboratory for Biolinguistics
Nanotubes are beacons in cancer-imaging technique
23.05.2016 | Rice University
More light on cancer
20.05.2016 | Lomonosov Moscow State University
Permanent magnets are very important for technologies of the future like electromobility and renewable energy, and rare earth elements (REE) are necessary for their manufacture. The Fraunhofer Institute for Mechanics of Materials IWM in Freiburg, Germany, has now succeeded in identifying promising approaches and materials for new permanent magnets through use of an in-house simulation process based on high-throughput screening (HTS). The team was able to improve magnetic properties this way and at the same time replaced REE with elements that are less expensive and readily available. The results were published in the online technical journal “Scientific Reports”.
The starting point for IWM researchers Wolfgang Körner, Georg Krugel, and Christian Elsässer was a neodymium-iron-nitrogen compound based on a type of...
In the Beyond EUV project, the Fraunhofer Institutes for Laser Technology ILT in Aachen and for Applied Optics and Precision Engineering IOF in Jena are developing key technologies for the manufacture of a new generation of microchips using EUV radiation at a wavelength of 6.7 nm. The resulting structures are barely thicker than single atoms, and they make it possible to produce extremely integrated circuits for such items as wearables or mind-controlled prosthetic limbs.
In 1965 Gordon Moore formulated the law that came to be named after him, which states that the complexity of integrated circuits doubles every one to two...
Characterization of high-quality material reveals important details relevant to next generation nanoelectronic devices
Quantum mechanics is the field of physics governing the behavior of things on atomic scales, where things work very differently from our everyday world.
When current comes in discrete packages: Viennese scientists unravel the quantum properties of the carbon material graphene
In 2010 the Nobel Prize in physics was awarded for the discovery of the exceptional material graphene, which consists of a single layer of carbon atoms...
The trend-forward world of display technology relies on innovative materials and novel approaches to steadily advance the visual experience, for example through higher pixel densities, better contrast, larger formats or user-friendler design. Fraunhofer ISC’s newly developed materials for optics and electronics now broaden the application potential of next generation displays. Learn about lower cost-effective wet-chemical printing procedures and the new materials at the Fraunhofer ISC booth # 1021 in North Hall D during the SID International Symposium on Information Display held from 22 to 27 May 2016 at San Francisco’s Moscone Center.
24.05.2016 | Event News
20.05.2016 | Event News
19.05.2016 | Event News
25.05.2016 | Trade Fair News
25.05.2016 | Life Sciences
25.05.2016 | Power and Electrical Engineering