Category: Memory

 Eyewitnesses play a key role in police investigations. But how likely is it that they remember correctly? Today the police place far too much emphasis on eyewitness accounts, according to Farhan Sarwar from Lund University in Sweden, who will be defending his PhD thesis on witness psychology shortly.

Those who have witnessed a crime would do best not to tell anyone about it. Contrary to what one might believe, a person's memory of an event is not improved by retelling the story. Instead, the risk of an incorrect account increases the more the story is retold and discussed.

"The most accurate witness statements come from people who have seen a crime and then write down what happened before they recount it or discuss it with anyone," says Farhan Sarwar.

However, it is quite unusual for witnesses to do this. On the contrary, many want to immediately discuss what they have seen. One example of how wrong they can be is the eyewitness descriptions of Anna Lindh's murderer. Those who were there and saw the murderer were in agreement that he was wearing military clothing. When the pictures from the department store's cameras were examined, it could be seen that he was wearing normal sports clothes.

Farhan Sarwar's studies show that eyewitnesses are particularly bad at remembering details, such as what the perpetrator was wearing or what weapon was used. On the other hand, they are better at recalling the key events.

A witness who has told his story many times may become increasingly sure of the details of the crime. This could have devastating consequences for a criminal investigation, as the police place great importance on how confident the witness is, says Farhan Sarwar.

But if eyewitness accounts are so flawed, should they be used at all?

"Yes," says Farhan Sarwar. "Criminals are getting increasingly canny. They rarely leave any clues. Therefore, eyewitness accounts are still the most important thing the police have to go on. However, the police must be aware of how much importance they attribute to them."

Alongside the work on his thesis, Farhan Sarwar has developed a method to measure the likelihood of eyewitness accounts being correct, together with colleague Sverker Sikström. He has written a computer program that uses algorithms to give a reliable percentage figure for how likely it is that an eyewitness really has remembered correctly.

Testing on the method is not yet complete, but when it is ready the program will quickly be able to process a large number of recorded witness statements. He can already see a number of areas for use: courts, police questioning, security services, insurance companies, etc.

Download the thesis Eyewitness testimonies: The memory and meta-memory effects of retellings and discussions with non-witnesses.

— Put down those science text books and work at recalling information from memory. That's the shorthand take away message of new research from Purdue University that says practicing memory retrieval boosts science learning far better than elaborate study methods.

"Our view is that learning is not about studying or getting knowledge 'in memory,'" said Purdue psychology professor Jeffrey Karpicke, the lead investigator for the study that appears January 20 in the journal Science. "Learning is about retrieving. So it is important to make retrieval practice an integral part of the learning process."

Educators traditionally rely on learning activities that encourage elaborate study routines and techniques focused on improving the encoding of information into memory. But, when students practice retrieval, they set aside the material they are trying to learn and instead practice calling it to mind.

The study, "Retrieval Practice Produces More Learning Than Elaborative Studying With Concept Mapping," tested both learning strategies alongside each other. The research was funded by the National Science Foundation's Division of Undergraduate Education.

"In prior research, we established that practicing retrieval is a powerful way to improve learning," said Karpicke. "Here we put retrieval practice to the test by comparing its effectiveness to an elaborative study method, specifically elaborative studying by creating concept maps."

Concept mapping requires students to construct a diagram–typically using nodes or bubbles–that shows relationships among ideas, characteristics or materials. These concepts are then written down as a way of encoding them in a person's memory.

The researchers say the practice is used extensively for learning about concepts in sciences such as biology, chemistry or physics.

In two studies, reported by Karpicke and his colleague, Purdue University psychology student Janell Blunt, a total of 200 students studied texts on topics from different science disciplines. One group engaged in elaborative study using concept maps while a second group practiced retrieval; they read the texts, then put them away and practiced freely recalling concepts from the text.

After an initial study period, both groups recalled about the same amount of information. But when the students returned to the lab a week later to assess their long-term learning, the group that studied by practicing retrieval showed a 50 percent improvement in long-term retention above the group that studied by creating concept maps.

This, despite the students own predictions about how much they would actually remember. "Students do not always know what methods will produce the best learning," said Karpicke in discussing whether students are good at judging the success of their study habits.

He found that when students have the material right in front of them, they think they know it better than they actually do. "It may be surprising to realize that there is such a disconnect between what students think will afford good learning and what is actually best. We, as educators, need to keep this in mind as we create learning tools and evaluate educational practices," he said.

The researchers showed retrieval practice was superior to elaborative studying in all comparisons.

"The final retention test was one of the most important features of our study, because we asked questions that tapped into meaningful learning," said Karpicke.

The students answered questions about the specific concepts they learned as well as inference questions asking them to draw connections between things that weren't explicitly stated in the material. On both measures of meaningful learning, practicing retrieval continued to produce better learning than elaborative studying.

Karpicke says there's nothing wrong with elaborative learning, but argues that a larger place needs to be found for retrieval practice. "Our challenge now is to find the most effective and feasible ways to use retrieval as a learning activity–but we know that it is indeed a powerful way to enhance conceptual learning about science."

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Journal Reference:

1. J. D. Karpicke, J. R. Blunt. Retrieval Practice Produces More Learning than Elaborative Studying with Concept Mapping. Science, 2011; DOI: 10.1126/science.1199327

Neuroscientists at MIT's Picower Institute of Learning and Memory have uncovered why relatively minor details of an episode are sometimes inexplicably linked to long-term memories. The work is slated to appear in the Jan. 13 issue of Neuron.

"Our finding explains, at least partially, why seemingly irrelevant information like the color of the shirt of an important person is remembered as vividly as more significant information such as the person's impressive remark when you recall an episode of meeting this person," said co-author Susumu Tonegawa, Picower Professor of Biology and Neuroscience and director of the RIKEN-MIT Center for Neural Circuit Genetics.

The data also showed that irrelevant information that follows the relevant event rather than precedes it is more likely to be integrated into long-term memory.

Shaping a memory

One theory holds that memory traces or fragments are distributed throughout the brain as biophysical or biochemical changes called engrams. The exact mechanism underlying engrams is not well understood.

MIT neuroscientists Arvind Govindarajan, assistant director of the RIKEN/MIT Center for Neural Circuit Genetics; Picower Institute postdoctoral associate Inbal Israely; and technical associate Shu-Ying Huang; and Tonegawa looked at single neurons to explore how memories are created and stored in the brain.

Previous research has focused on the role of synapses — the connections through which neurons communicate. An individual synapse is thought to be the minimum unit necessary to establish a memory engram.

Instead of looking at individual synapses, the MIT study explored neurons' branch-like networks of dendrites and the multiple synapses within them.

Boosting the signal

Neurons sprout dendrites that transmit incoming electrochemical stimulation to the trunk-like cell body. Synapses located at various points act as signal amplifiers for the dendrites, which play a critical role in integrating synaptic inputs and determining the extent to which the neuron acts on incoming signals.

In response to external stimuli, dendritic spines in the cerebral cortex undergo structural remodeling, getting larger in response to repeated activity within the brain. This remodeling is thought to underlie learning and memory.

The MIT researchers found that a memory of a seemingly irrelevant detail — the kind of detail that would normally be relegated to a short-term memory–may accompany a long-term memory if two synapses on a single dendritic arbor are stimulated within an hour and a half of each other.

"A synapse that received a weak stimulation, the kind that would normally accompany a short-term memory, will express a correlate of a long-term memory if two synapses on a single dendritic branch were involved in a similar time frame," Govindarajan said.

This occurs because the weakly stimulated synapse can steal or hitchhike on a set of proteins synthesized at or near the strongly stimulated synapse. These proteins are necessary for the enlargement of a dendritic spine that allows the establishment of a long-term memory.

"Not all irrelevant information is recalled, because some of it did not stimulate the synapses of the dendritic branch that happens to contain the strongly stimulated synapse," Israely said.

Funding: RIKEN, the Howard Hughes Medical Institute and the National Institutes of Health.

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Journal Reference:

1. Arvind Govindarajan, Inbal Israely, Shu-Ying Huang and Susumu Tonegawa. The dendritic branch is the preferred integrative unit for protein synthesis-dependent LTP. Neuron, 13 January, 2011

 Research conducted by Iaroslav Savtchouk, a graduate student, and S. June Liu, PhD, Associate Professor of Cell Biology and Anatomy at LSU Health Sciences Center New Orleans, has shown that a single exposure to acute stress affected information processing in the cerebellum — the area of the brain responsible for motor control and movement coordination and also involved in learning and memory formation.

The work is published in the January 12, 2011 issue of The Journal of Neuroscience.

The researchers found that a five-minute exposure to the odor of a predator produced the insertion of receptors containing GluR2 at the connections (synapses) between nerve cells in the brain. GluR2 is a subunit of a receptor in the central nervous system that regulates the transfer of electrical impulses between nerve cells, or neurons. The presence of GluR2 changed electrical currents in the cerebellum in a way that increased activity and altered the output of the cerebellar circuit in the brains of mice.

Our ability to learn from experience and to adapt to our environment depends upon synaptic plasticity — the ability of a neuron or synapse to change its internal parameters in response to its history. A change in the GluR2 receptor subunit has been observed both during normal learning and memory as well as during many pathological processes, including drug addiction, stress, epilepsy, and ischemic stroke. However, the effect of this change on neuronal function is not fully understood.

"Our results lead to the testable prediction that emotional stress could affect motor coordination and other cerebellum-dependent cognitive functions," notes Dr. Liu. "These results are also applicable to communication in other brain regions and circuits. A long term goal is to alleviate the burden of neurological disorders such as motor dysfunctions, drug addiction, PTSD, and stroke." Next steps include further research to improve our understanding of the role GluR2 insertion plays in normal learning and functioning of the brain, why some neurons contain GluR2-lacking receptors, but not others, and how that affects their role in brain function.

The research was supported by grants from the National Science Foundation and the National Institutes of Health.

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Journal Reference:

1. I. Savtchouk, S. J. Liu. Remodeling of Synaptic AMPA Receptor Subtype Alters the Probability and Pattern of Action Potential Firing. Journal of Neuroscience, 2011; 31 (2): 501 DOI: 10.1523/JNEUROSCI.2608-10.2011

 Do the guidelines on interviewing alleged victims of child abuse need to be re-thought? New research from the University of Abertay Dundee has found evidence that multiple interviews can actually help victims recall greater details about their abuse.

Currently the guidelines for the UK and Scotland recommend investigators avoid repeated interviews wherever possible, arguing that this risks inconsistent evidence and 'suggestability' — the problem of an interviewer suggesting answers by not asking open-ended questions with multiple possible answers.

However, research by Dr David La Rooy and colleagues has found that when conducted properly, multiple interviews using open-ended questions can deliver stronger evidence to convict, and actually help alleged victims recall greater details about their experiences of abuse.

"When interviewers follow internationally recognised best-practice guidelines on using open questions and free-memory recall, more complete accounts of their abuse can be pieced together through conducting multiple interviews," Dr La Rooy said.

"It's commonly assumed that conducting more than one interview damages the quality of evidence, but our research has found that this isn't necessarily the case.

"When properly conducted, more than one interview helps victims' memories develop, revealing far greater detail than just one interview ever can."

Guidelines to investigators from both the UK Government in 2007 and the then Scottish Executive in 2003 recommend strongly against multiple interviews. However, the researchers found a strong body of psychological evidence suggesting otherwise.

Dr La Rooy added: "There is a need to distinguish between multiple interviews that are conducted properly and help a victim gradually recover their memory, and multiple interviews that are conducted poorly and lead a child to give particular answers.

"As guidelines are revised in the future we strongly hope that this evidence is taken into account."

The key psychological process is known as 'reminiscence', where an individual's memory is incomplete but can be gradually pieced back together over time. The researchers found that separating interviews gave time for additional, new information to be recalled.

The need to re-interview alleged victims also needs to be balanced with concerns about the welfare of victims, who can find the interviewing process extremely stressful and disturbing. However, the research shows that children can benefit from more than one opportunity to recall information.

Conducting a series of interviews, with structured and open-ended questioning, can allow the child to develop a trusting relationship with the interviewer and limit the negative effects of the process.

The research is published in the latest edition of Psychology, Public Policy and Law, the journal of the American Psychological Association.

Dr La Rooy worked with Dr Carmit Katz, Professor Michael Lamb and Dr Lindsay Malloy of Cambridge University on the paper.

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Journal Reference:

1. La Rooy et al. Do we need to rethink guidance on repeated interviews?Psychology, Public Policy, and Law, Volume 16, Issue 4, November 2010, Pages 373-392

 Yale University researchers have found that a single molecule not only connects brain cells but also changes how we learn. The findings, reported in the December 9 issue of the journal Neuron, may help researchers discover ways to improve memory and could lead to new therapies to correct neurological disorders.

The junctions between brain cells over which nerve pulses pass — called synapses — are crucial for regulating learning and memory and how we think. Aberrations in the structure and function of synapses have been linked to mental retardation and autism, while synapses are lost in the aging brains of Alzheimer's patients.

However, the mechanisms that organize synapses in the living brain remain a puzzle. Yale scientists identified one critical piece of this puzzle, a molecule called SynCAM 1 that spans across synaptic junctions.

"We hypothesized that this molecule might promote new synapses in the developing brain, but were surprised that it also impacts the maintenance and function of these structures," said Thomas Biederer, associate professor of molecular biophysics and biochemistry and senior author of the study. "We can now define how this molecule supports the brain's ability to wire itself."

The Yale team focused on SynCAM 1, an adhesion molecule that helps to hold synaptic junctions together. They found that when the SynCAM 1 gene was activated in mice, more synaptic connections formed. Mice without the molecule produced fewer synapses.

When we learn, new synapses can form. However, the strength of synaptic connections also changes during learning, based on the amount of stimuli received — a quality scientists termed "plasticity." Together with a group in Germany led by Valentin Stein, the team was surprised to find that SynCAM 1 controls an important form of synaptic plasticity.

Unexpectedly, Biederer and colleagues also found that mice with high amounts of SynCAM 1 are unable to learn while mice lacking SynCAM 1 — and having fewer synapses — learn better. Apparently an excess of the molecule can be damaging. This builds on recent theories suggesting that having too many connections isn't always better and that the balance of synaptic activity is crucial for proper learning and memory.

"Synapses are dynamic structures. It appears that SynCAM 1 ties synapses together; some of this molecule is needed to promote contact but too much glues down the synapse and inhibits its function. It may act a bit like a sculptor who helps give synapses their shape." Biederer also said that the molecule is almost identical in mice and man, and likely has the same roles in human brains.

Other Yale authors on the paper are Elissa Robbins and Karen Perez de Arce.

The work was funded by the National Institutes of Health and the March of Dimes Foundation.

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Journal Reference:

1. Elissa M. Robbins, Alexander J. Krupp, Karen Perez De Arce, Ananda K. Ghosh, Adam I. Fogel, Antony Boucard, Thomas C. Südhof, Valentin Stein, Thomas Biederer. SynCAM 1 adhesion dynamically regulates synapse number and impacts plasticity and learning. Neuron, 2010; 68 (5): 894-906 DOI: 10.1016/j.neuron.2010.11.003

Medical researchers have found a missing link that explains the interaction between brain state and the neural triggers responsible for learning, potentially opening up new ways of boosting cognitive function in the face of diseases such as Alzheimer's as well as enhancing memory in healthy people.

Much is known about the neural processes that occur during learning but until now it has not been clear why it occurs during certain brain states but not others. Now researchers from the University of Bristol have been able to study, in isolation, the specific neurotransmitter which enhances learning and memory.

Acetylcholine is released in the brain during learning and is critical for the acquisition of new memories. Its role is to facilitate the activity of NMDA receptors, proteins that control the strength of connections between nerve cells in the brain.

Currently, the only effective treatment for the symptoms of cognitive impairment seen in diseases such as Alzheimer's is through the use of drugs that boost the amount of acetylcholine release and thereby enhance cognitive function.

Describing their findings in the journal Neuron, researchers from Bristol's School of Physiology and Pharmacology have shown that acetylcholine facilitates NMDA receptors by inhibiting the activity of other proteins called SK channels whose normal role is to restrict the activity of NMDA receptors.

This discovery of a role for SK channels provides new insight into the mechanisms underlying learning and memory. SK channels normally act as a barrier to NMDA receptor function, inhibiting changes in the strength of connections between nerve cells and therefore restricting the brain's ability to encode memories. Findings from this latest research show that the SK channel barrier can be removed by the release of acetylcholine in the brain in order to enhance our ability to learn and remember information.

Lead researcher Dr Jack Mellor, from the University of Bristol's Medical School, said: "These findings are not going to revolutionise the treatment of Alzheimer's disease or other forms of cognitive impairment overnight. However, national and international funding bodies have recently made research into aging and dementia a top priority so we expect many more advances in our understanding of the mechanisms underlying learning and memory in both health and disease."

The team studied the effects of drugs that target acetylcholine receptors and SK channels on the strength of connections between nerve cells in animal brain tissue. They found that changes in connection strength were facilitated by the presence of drugs that activate acetylcholine receptors or block SK channels revealing the link between the two proteins.

Dr Mellor added: "From a therapeutic point of view, this study suggests that certain drugs that act on specific acetylcholine receptors may be highly attractive as potential treatments for cognitive disorders. Currently, the only effective treatments for patients with Alzheimer's disease are drugs that boost the effectiveness of naturally released acetylcholine. We have shown that mimicking the effect of acetylcholine at specific receptors facilitates changes in the strength of connections between nerve cells. This could potentially be beneficial for patients suffering from Alzheimer's disease or schizophrenia."

The research team involved the University of Bristol's MRC Centre for Synaptic Plasticity and the Division of Neuroscience in the School of Physiology & Pharmacology, part of the Bristol Neuroscience network. This work was supported by the Wellcome Trust, MRC, BBSRC and GSK.

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Journal Reference:

1. Buchanan KA, Petrovic MM, Chamberlain SEL, Marrion NV & Mellor JR. Facilitation of Long-Term Potentiation by Muscarinic M1 Receptors is mediated by inhibition of SK channels. Neuron, DOI: 10.1016/j.neuron.2010.11.018

 Good news for control freaks! New research confirms that having some authority over how one takes in new information significantly enhances one's ability to remember it. The study, in the journal Nature Neuroscience, also offers a first look at the network of brain structures that contribute to this phenomenon.

"Having active control over a learning situation is very powerful and we're beginning to understand why," said University of Illinois psychology professor Neal Cohen, who led the study with postdoctoral researcher Joel Voss. "Whole swaths of the brain not only turn on, but also get functionally connected when you're actively exploring the world."

The study focused on activity in several brain regions, including the hippocampus, located in the brain's medial temporal lobes, near the ears. Researchers have known for decades that the hippocampus is vital to memory, in part because those who lose hippocampal function as a result of illness or injury also lose their ability to fully form and retain new memories.

But the hippocampus doesn't act alone. Robust neural connections tie it to other important brain structures, and traffic on these data highways flows in both directions. Functional magnetic resonance imaging (fMRI) studies, which track blood flow in the brain, show that the hippocampus is functionally connected to several brain networks — distinct regions of the brain that work in tandem to accomplish critical tasks.

To better understand how these brain regions influence active versus passive learning, Voss designed an experiment that required participants to memorize an array of objects and their exact locations in a grid on a computer monitor. A gray screen with a window in it revealed only one object at a time. The "active" study subjects used a computer mouse to guide the window to view the objects.

"They could inspect whatever they wanted, however they wanted, in whatever order for however much time they wanted, and they were just told to memorize everything on the screen," Voss said. The "passive" learners viewed a replay of the window movements recorded in a previous trial by an active subject.

Then participants were asked to select the items they had seen and place them in their correct positions on the screen. After a trial, the active and passive subjects switched roles and repeated the task with a new array of objects.

The study found significant differences in brain activity in the active and passive learners. Those who had active control over the viewing window were significantly better than their peers at identifying the original objects and their locations, the researchers found. Further experiments, in which the passive subjects used a mouse that moved but did not control the viewing window, established that this effect was independent of the act of moving the mouse.

To identify the brain mechanisms that enhanced learning in the active subjects, the researchers repeated the trials, this time testing individuals who had amnesia — a disease characterized by impairment in learning new information — as a result of hippocampal damage. To the surprise of the researchers, these participants failed to benefit from actively controlling the viewing window.

"These data suggest that the hippocampus has a role not just in the formation of new memory but possibly also in the beneficial effects of volitional control on memory," the researchers wrote.

Brain imaging (by means of fMRI) of healthy young subjects engaged in the same active and passive learning tests revealed that hippocampal activity was highest in the active subjects' brains during these tests. Several other brain structures were also more engaged when the subject controlled the viewing window, and activity in these brain regions was more synchronized with that of the hippocampus than in the passive trials.

Activity in the dorsolateral prefrontal cortex, the cerebellum and the hippocampus was higher, and more highly coordinated, in participants who did well on spatial recall, the researchers found. Increased activity in the inferior parietal lobe, the parahippocampal cortex and the hippocampus corresponded to better performance on item recognition.

"Lo and behold," Cohen said, "our friend the hippocampus makes a very conspicuous appearance in active learning."

The new findings challenge previous ideas about the role of the hippocampus in learning, Voss said. It is a surprise, he said, that other brain regions that are known to be involved in planning and strategizing, for instance, "can't do very much unless they can interact with the hippocampus."

Rather than being a passive player in learning, the hippocampus "is more like an integral part of an airplane guidance system," Voss said. "You have all this velocity information, you have a destination target and every millisecond it's taking in information about where you're headed, comparing it to where you need to go, and correcting and updating it."

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Journal Reference:

1. Joel L Voss, Brian D Gonsalves, Kara D Federmeier, Daniel Tranel, Neal J Cohen. Hippocampal brain-network coordination during volitional exploratory behavior enhances learning. Nature Neuroscience, 2010; DOI: 10.1038/nn.2693

— Memory difficulties such as those seen in dementia may arise because the brain forms incomplete memories that are more easily confused, new research from the University of Cambridge has found.

The findings are published December 2 in the journal Science.

Currently, memory problems are typically perceived to be the result of forgetting previously encountered items or events. The new research (using an animal model of amnesia), however, found that the ability of the brain to maintain complete, detailed memories is disrupted. The remaining, less detailed memories are relatively easily confused, leading to an increased likelihood of falsely remembering information that was not encountered.

Dr Lisa Saksida, from the Department of Experimental Psychology at the University of Cambridge, said: "This study suggests that a major component of memory problems may actually be confusion between memories, rather than loss of memories per se.

"This is consistent with reports of memory distortions in dementia — for example, patients may not switch off the cooker, or may fail to take their medication, not because they have forgotten that they should do these things, but because they think they have already done so."

Previous research on memory found that amnesic animals couldn't distinguish between a new and an old object. However, these studies didn't demonstrate whether the animal was unable to distinguish between the objects because it saw the old object as being new (it has forgotten something that occurred), or because it saw the new object as being old (false memory).

In order to examine which is indeed the case, the researchers developed a new experimental method that allows them to analyze responses to the new and the old objects separately. Animals were allowed to look at an object and then, after an hour, were given a memory test in which they were either shown the same object again, or a new object. Normal animals spent more time exploring the new object, indicating that they remembered the old object.

Amnesic animals, however, performed poorly on the memory task, as they spent an equal amount of time exploring the old and the new object. Interestingly, the amnesic animals explored the new object less than the normal animals did, indicating false memory for the new object.

The researchers concluded that the memory problems were the result of the brain's inability to register complete memories of the objects, and that the remaining, less detailed memories were more easily confused.

The scientists, funded by the Biotechnology and Biological Sciences Research Council (BBSRC), then used this knowledge to examine whether they could improve performance on the memory task if there were not other memories to confuse the brain. To do this, they placed the animals in a dark, quiet space (rather than the usual busy environment) before the memory test. Amnesic animals who showed no recollection when they spent the time before the memory test in normal, busy conditions, showed perfect memory when they spent the time before the memory test in a dark, quiet environment.

Dr Saksida continued, "One thing that we found very surprising about our results was the extent of the memory recovery, achieved simply by reducing the incoming information prior to the memory test.

"Not only does this result confound our expectations, but it also gives us a clearer understanding of the possible nature of the memory impairment underlying amnesia and certain types of dementia, which is critical to developing more sophisticated and effective treatments."

"This also tells us something about how detrimental interference from other things can be when we are trying to remember something, an issue that may be increasingly relevant as the number of potential distractions in our daily lives seems to be on the rise."

The researchers hope that their research could lead to new treatments that reduce the confusion between memories, perhaps with the development of drugs that can enhance the complex, detailed representations that are required to separate memories.

Dr Saksida commented on the possibility of new treatments, stating: "Alternatively, deliberate and intentional use of the details differentiating objects and events might be a strategy that could prolong independence and help to improve daily functioning for patients.

"Even more exciting would be the ability to develop treatments that could stop the disease in the early stages, rather than treatments that address the symptoms once dementia has set in. Early detection of memory impairment is critical for the development of such treatments, and a better understanding of the nature of the impairment, as we have found here, is critical to such early detection."

Additional support was provided by the Medical Research Council and the Wellcome Trust through their funding of the University of Cambridge's Behavioural and Clinical Neuroscience Institute.

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Journal Reference:

1. S. M. McTighe, R. A. Cowell, B. D. Winters, T. J. Bussey, L. M. Saksida. Paradoxical False Memory for Objects After Brain Damage. Science, 2010; 330 (6009): 1408 DOI: 10.1126/science.1194780