A central question has been whether the hippocampus receives an "episodic packet," or a collection of perceptual strands that it must integrate into a memory.
In an article in the November 9, 2006, issue of the journal Neuron, published by Cell Press, Melina Uncapher and colleagues report experiments with human volunteers that shed important light on this process.
In their experiments, the researchers presented the subjects with series of "study" words on a display screen, as their brains were scanned using functional magnetic resonance imaging (fMRI). This technique involves using harmless radio waves and magnetic fields to measure blood flow to brain regions, which reflects brain activity. As their brains were scanned, the subjects were shown words of different colors and that were located in different quadrants of the display screen.
Later, the subjects were presented a collection of words including both the study words and new words. They were asked to recall whether the words were old or new, and for the old words, their color and location.
The researchers then correlated fMRI data on the brain regions active during the study phase with the data on the subjects' later retrieval of the features of these study words. They found that, indeed, regions of the brain involved in processing color and location were active during formation of memories for those features.
However, importantly, they found that the subjects' successful retrieval of both features--versus only color or location--was uniquely associated with enhanced activity in yet another brain region called the intraparietal sulcus, which has been strongly implicated in other studies as important in "perceptual binding" of multiple features of stimuli.
Thus, the researchers concluded that "The findings suggest that the encoding of disparate features of an episode into a common memory representation requires that the features be conjoined in a common perceptual representation when the episode is initially experienced."
Asian dust providing key nutrients for California's giant sequoias
28.03.2017 | University of California - Riverside
Chlamydia: How bacteria take over control
28.03.2017 | Julius-Maximilians-Universität Würzburg
The Institute of Semiconductor Technology and the Institute of Physical and Theoretical Chemistry, both members of the Laboratory for Emerging Nanometrology (LENA), at Technische Universität Braunschweig are partners in a new European research project entitled ChipScope, which aims to develop a completely new and extremely small optical microscope capable of observing the interior of living cells in real time. A consortium of 7 partners from 5 countries will tackle this issue with very ambitious objectives during a four-year research program.
To demonstrate the usefulness of this new scientific tool, at the end of the project the developed chip-sized microscope will be used to observe in real-time...
Astronomers from Bonn and Tautenburg in Thuringia (Germany) used the 100-m radio telescope at Effelsberg to observe several galaxy clusters. At the edges of these large accumulations of dark matter, stellar systems (galaxies), hot gas, and charged particles, they found magnetic fields that are exceptionally ordered over distances of many million light years. This makes them the most extended magnetic fields in the universe known so far.
The results will be published on March 22 in the journal „Astronomy & Astrophysics“.
Galaxy clusters are the largest gravitationally bound structures in the universe. With a typical extent of about 10 million light years, i.e. 100 times the...
Researchers at the Goethe University Frankfurt, together with partners from the University of Tübingen in Germany and Queen Mary University as well as Francis Crick Institute from London (UK) have developed a novel technology to decipher the secret ubiquitin code.
Ubiquitin is a small protein that can be linked to other cellular proteins, thereby controlling and modulating their functions. The attachment occurs in many...
In the eternal search for next generation high-efficiency solar cells and LEDs, scientists at Los Alamos National Laboratory and their partners are creating...
Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are less stable. Now researchers at the Technical University of Munich (TUM) have, for the first time ever, produced a composite material combining silicon nanosheets and a polymer that is both UV-resistant and easy to process. This brings the scientists a significant step closer to industrial applications like flexible displays and photosensors.
Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are...
20.03.2017 | Event News
14.03.2017 | Event News
07.03.2017 | Event News
28.03.2017 | Physics and Astronomy
28.03.2017 | Health and Medicine
28.03.2017 | Life Sciences