For a paper to be published in the July edition of the journal Psychological Science, researchers gave participants material to remember in two experimental sessions -- once after being injected with a saline placebo and once after an injection of midazolam, a drug used to relieve anxiety during surgical procedures that also causes short-term anterograde amnesia, the most common form of amnesia. Anterograde amnesia, which was portrayed in the film "Memento," impairs a person's ability to form new memories while leaving old ones unharmed.
The study revealed that the drug prevented people from linking a studied item to the experimental context. That linkage is necessary for a process known as recollection, in which people retrieve contextual details involved in the experience of studying the information. People sometimes recognize something as having been studied without using recollection (in this case, without remembering details of the study event) if the item seems sufficiently familiar -- a process called familiarity. Although the recollection process was affected by the drug, the familiarity process was not. This is the same pattern that is found with patients suffering from anterograde amnesia. They are unable to form new associations, severely limiting the accuracy of their recognition judgments.
"This helps us understand the general functions of memory. It helps us to relate, for example, the memory declines seen in old age to those seen in patients with hippocampal damage," said Lynne Reder, a professor of psychology at Carnegie Mellon and the study's lead author.
Using a double-blind, within-subject protocol, the scientists compared the participants' performance on the test after studying the material either under the influence of midazolam or after receiving an injection of a saline placebo. In both sessions, participants viewed words, photographs of faces and landscapes, and abstract pictures one at a time on a computer screen. Twenty minutes later, they were shown the words and images again, one at a time. Half of the images they had seen earlier, and half were new. They were then asked whether they recognized each one.
The researchers predicted that the more participants relied on recollection with saline, the more they would be hurt under the influence of midazolam. Their findings matched those predictions. Researchers found that the participants' memory while in the placebo condition was best for words, but the worst for abstract images. Midazolam impaired the recognition of words the most and did not affect recognition of abstract pictures.
The experiment further reinforced the thought that the ability to recollect depends on the ability to link the stimulus to a context. While the words were very concrete and therefore easy to link to the experimental context, the photographs were of unknown people and unknown places (not, for example, of Marilyn Monroe or the Eiffel Tower) and thus hard to distinctively label. The abstract images were also unfamiliar and not unitized into something that could be described with a single word (such as Picasso's "Guernica"). This meant that a person could not easily link the image with a context, regardless of drug condition.
Jonathan Potts | EurekAlert!
Diagnoses: When Are Several Opinions Better Than One?
19.07.2016 | Max-Planck-Institut für Bildungsforschung
High in calories and low in nutrients when adolescents share pictures of food online
07.04.2016 | University of Gothenburg
Researchers from the Institute for Quantum Computing (IQC) at the University of Waterloo led the development of a new extensible wiring technique capable of controlling superconducting quantum bits, representing a significant step towards to the realization of a scalable quantum computer.
"The quantum socket is a wiring method that uses three-dimensional wires based on spring-loaded pins to address individual qubits," said Jeremy Béjanin, a PhD...
In a paper in Scientific Reports, a research team at Worcester Polytechnic Institute describes a novel light-activated phenomenon that could become the basis for applications as diverse as microscopic robotic grippers and more efficient solar cells.
A research team at Worcester Polytechnic Institute (WPI) has developed a revolutionary, light-activated semiconductor nanocomposite material that can be used...
By forcefully embedding two silicon atoms in a diamond matrix, Sandia researchers have demonstrated for the first time on a single chip all the components needed to create a quantum bridge to link quantum computers together.
"People have already built small quantum computers," says Sandia researcher Ryan Camacho. "Maybe the first useful one won't be a single giant quantum computer...
COMPAMED has become the leading international marketplace for suppliers of medical manufacturing. The trade fair, which takes place every November and is co-located to MEDICA in Dusseldorf, has been steadily growing over the past years and shows that medical technology remains a rapidly growing market.
In 2016, the joint pavilion by the IVAM Microtechnology Network, the Product Market “High-tech for Medical Devices”, will be located in Hall 8a again and will...
'Ferroelectric' materials can switch between different states of electrical polarization in response to an external electric field. This flexibility means they show promise for many applications, for example in electronic devices and computer memory. Current ferroelectric materials are highly valued for their thermal and chemical stability and rapid electro-mechanical responses, but creating a material that is scalable down to the tiny sizes needed for technologies like silicon-based semiconductors (Si-based CMOS) has proven challenging.
Now, Hiroshi Funakubo and co-workers at the Tokyo Institute of Technology, in collaboration with researchers across Japan, have conducted experiments to...
14.10.2016 | Event News
14.10.2016 | Event News
12.10.2016 | Event News
21.10.2016 | Health and Medicine
21.10.2016 | Information Technology
21.10.2016 | Materials Sciences