How Driving a Taxi Changes London Cabbies’ Brains

Every black-cab driver in central London has to have “The Knowledge” — a memorized map of the capital, including some 25,000 streets and thousands of landmarks, right down to the order of theaters on Shaftesbury Avenue.

It’s a brutal learning process that can take three to four years to complete, with a final test — the Knowledge of London Examination System — that often takes 12 attempts to pass. Even then, ultimately only half of the trainee cabbies ace the exam.

According to a report published in the journal Current Biology, successfully learning this mental atlas of London’s spaghetti streets causes structural changes in the brain, affects memory and creates a greater volume of nerve cells in the brain’s hippocampus.

Forget All-Night Studying, a Good Night’s Sleep Is Key to Doing Well on Exams

As fall semesters wind down at the country’s colleges and universities, students will be pulling all-night study sessions to prepare for final exams. Ironically, the loss of sleep during these all-nighters could actually work against them performing well, says a Harris Health System sleep specialist.

Dr. Philip Alapat, medical director, Harris Health Sleep Disorders Center, and assistant professor, Baylor College of Medicine, recommends students instead study throughout the semester, set up study sessions in the evening (the optimal time of alertness and concentration) and get at least 8 hours of sleep the night before exams.

“Memory recall and ability to maintain concentration are much improved when an individual is rested,” he says. “By preparing early and being able to better recall what you have studied, your ability to perform well on exams is increased.”

Alapat’s recommendations:
• Get 8-9 hours of sleep nightly (especially before final exams)

• Try to study during periods of optimal brain function (usually around 6-8 p.m.)

• Avoid studying in early afternoons, usually the time of least alertness

• Don’t overuse caffeinated drinks (caffeine remains in one’s system for 6-8 hours)

• Recognize that chronic sleep deprivation may contribute to development of long-term diseases like diabetes, high blood pressure and heart disease

If suffering from bouts of chronic sleep deprivation or nightly insomnia that lasts for more than a few weeks, Alapat suggests consulting a sleep specialist.

The Future of Memory: Remembering, Imagining, and the Brain

During the past few years, there has been a dramatic increase in research examining the role of memory in imagination and future thinking. This work has revealed striking similarities between remembering the past and imagining or simulating the future, including the finding that a common brain network underlies both memory and imagination. Here, we discuss a number of key points that have emerged during recent years, focusing in particular on the importance of distinguishing between temporal and nontemporal factors in analyses of memory and imagination, the nature of differences between remembering the past and imagining the future, the identification of component processes that comprise the default network supporting memory-based simulations, and the finding that this network can couple flexibly with other networks to support complex goal-directed simulations. This growing area of research has broadened our conception of memory by highlighting the many ways in which memory supports adaptive functioning.

Brain waves encode rules for behavior

One of the biggest puzzles in neuroscience is how our brains encode thoughts, such as perceptions and memories, at the cellular level. Some evidence suggests that ensembles of neurons represent each unique piece of information, but no one knows just what these ensembles look like, or how they form.

A new study from researchers at MIT and Boston University (BU) sheds light on how neural ensembles form thoughts and support the flexibility to change one’s mind. The research team, led by Earl Miller, the Picower Professor of Neuroscience at MIT, identified groups of neurons that encode specific behavioral rules by oscillating in synchrony with each other.

The results suggest that the nature of conscious thought may be rhythmic, according to the researchers, who published their findings in the Nov. 21 issue of Neuron.

“As we talk, thoughts float in and out of our heads. Those are all ensembles forming and then reconfiguring to something else. It’s been a mystery how the brain does this,” says Miller, who is also a member of MIT’s Picower Institute for Learning and Memory. “That’s the fundamental problem that we’re talking about — the very nature of thought itself.”

Neural interaction in periods of silence

While in deep dreamless sleep, our hippocampus sends messages to our cortex and changes its plasticity, possibly transferring recently acquired knowledge to long-term memory. But how exactly is this done? Scientists from the Max Planck Institute for Biological Cybernetics have now developed a novel multimodal methodology called “neural event-triggered functional magnetic resonance imaging” (NET-fMRI) and presented the very first results obtained using it in experiments with both anesthetized and awake, behaving monkeys. The new methodology uses multiple-contact electrodes in combination with functional magnetic resonance imaging (fMRI) of the entire brain to map widespread networks of neurons that are activated by local, structure-specific neural events.

Research shows diabetes drug improves memory

An FDA-approved drug initially used to treat insulin resistance in diabetics has shown promise as a way to improve cognitive performance in some people with Alzheimer’s disease.

Working with genetically engineered mice designed to serve as models for Alzheimer’s, University of Texas Medical Branch at Galveston researchers found that treatment with the anti-insulin-resistance drug rosiglitazone enhanced learning and memory as well as normalized insulin resistance. The scientists believe that the drug produced the response by reducing the negative influence of Alzheimer’s on the behavior of a key brain-signaling molecule.

The molecule, called extracellular signal-regulated kinase (ERK), becomes hyperactive both in the brains of Alzheimer’s patients and in the mice at a disease stage corresponding to mild cognitive impairment in human Alzheimer’s. This excessive activity leads to improper synaptic transmission between neurons, interfering with learning and memory.

Rosiglitazone brings ERK back into line by activating what’s known as the peroxisome proliferator-activated receptor gamma (PPARγ) pathway, which interacts with genes that respond to both PPARγ and ERK.

“Using this drug appears to restore the neuronal signaling required for proper cognitive function,” said UTMB professor Larry Denner, the lead author of a paper describing this work now online (posted Nov. 21)  in the Journal of Neuroscience. “It gives us an opportunity to test several FDA-approved drugs to normalize insulin resistance in Alzheimer’s patients and possibly also enhance memory, and it also gives us a remarkable tool to use in animal models to understand the molecular mechanisms that underlie cognitive issues in Alzheimer’s.”

Experimental Drug Improves Memory in Mice with Multiple Sclerosis

Johns Hopkins researchers report the successful use of a form of MRI to identify what appears to be a key biochemical marker for cognitive impairment in the brains of people with multiple sclerosis (MS). In follow-up experiments on mice with a rodent form of MS, researchers were able to use an experimental compound to manipulate that same marker and dramatically improve learning and memory.

Half of people with MS experience learning and memory problems, for which there is no approved treatment, along with movement abnormalities that characterize the debilitating autoimmune disorder.

"We have a potentially novel treatment for cognitive impairment in MS, a devastating condition on the rise that affects at least 400,000 people in the United States," says study leader Adam I. Kaplin, M.D., Ph.D., an assistant professor of psychiatry and behavioral sciences and neurology at the Johns Hopkins University School of Medicine.

Kaplin cautions that the treatment has so far been used only in mouse models of MS and is years away from clinical trials in people.

Nevertheless, he says, the research, described in the Proceedings of the National Academy of Sciences published online on Nov. 19, has the potential to speed development of new drugs to treat cognitive impairment not only in MS patients, but also in patients with Alzheimer’s disease and other neurological conditions.

Socrates Method Of Memory Works Just As Well Using Virtual Reality

In the episode of NOVA that aired October 24 of this year, host David Pogue posed the question, “How Smart Can We Get?” At one point in the episode, he met with Chester Santos, who was the 2008 US Memory Champion, to pick his brain on how he manages to learn long strings of numbers and words. Santos taught him a technique that involved visualization of objects that were in Pogue’s own house and associating them with the string of non-related words. It turns out this technique is nothing new. Its roots stem all the way back to the time of Socrates, in fact.

A new research study conducted by a team from the University of Alberta has revisited this age old technique giving it a modern-day twist.

The memory technique, called loci, or location, by the ancient Greeks, was used by Socrates, according to classic scholars, to memorize his oratories. To do this, Socrates would wander around his home and assign a word or fact that he needed to memorize some familiar object or structure in his home.

At the time that Socrates needed to recall this information in front of an audience, he would simply conjure up his home and, in his mind, the words that he had linked to things like his window or table would instantly be recalled.

“Nowadays many contestants in memory competitions use this same technique,” said lead researcher Eric Legge. “They use the location method to instantly recall everything from words to a long list of random numbers.”

Legge, along with his U of A research colleague Christopher Madan, developed a virtual living-space environment. This virtual living room would allow their test subjects to use the ancient Greek technique to increase their memory ability.

Teenagers’ brains affected by preterm birth

New research at the University of Adelaide has demonstrated that teenagers born prematurely may suffer brain development problems that directly affect their memory and learning abilities.

The research, conducted by Dr Julia Pitcher and Dr Michael Ridding from the University of Adelaide’s Robinson Institute, shows reduced ‘plasticity’ in the brains of teenagers who were born preterm (at or before 37 weeks gestation).

The results of the research are published in the Journal of Neuroscience.

"Plasticity in the brain is vital for learning and memory throughout life," Dr Pitcher says. "It enables the brain to reorganise itself, responding to changes in environment, behaviour and stimuli by modifying the number and strength of connections between neurons and different brain areas. Plasticity is also important for recovery from brain damage.

"We know from past research that preterm-born children often experience motor, cognitive and learning difficulties. The growth of the brain is rapid between 20 and 37 weeks gestation, and being born even mildly preterm appears to subtly but significantly alter brain microstructure, neural connectivity and neurochemistry.

"However, the mechanisms that link this altered brain physiology with behavioural outcomes - such as memory and learning problems - have remained unknown," Dr Pitcher says.

Newborn Neurons — Even in the Adult Aging Brain - are Critical for Memory

Newly generated, or newborn neurons in the adult hippocampus are critical for memory retrieval, according to a study led by Stony Brook University researchers published online in Nature Neuroscience. The functional role of newborn neurons in the brain is controversial, but in “Optical controlling reveals time-dependent roles for adult-born dentate granule cells,” the researchers detail that by ‘silencing’ newborn neurons, memory retrieval was impaired. The findings support the idea that the generation of new neurons in the brain may be crucial to normal learning and memory processes.

Previous research by the study’s lead investigator Shaoyu Ge, PhD, Assistant Professor in the Department of Neurobiology & Behavior at Stony Brook University, and others have demonstrated that newborn neurons form connections with existing neurons in the adult brain. To help determine the role of newborn neurons, Dr. Ge and colleagues devised a new optogenetic technique to control newborn neurons and test their function in the hippocampus, one of the regions of the brain that generates new neurons, even in the adult aging brain.

“Significant controversy has surrounded the functional role of newborn neurons in the adult brain,” said Dr. Ge. “We believe that our study results provide strong support to the idea that new neurons are important for contextual fear memory and spatial navigation memory, two essential aspects of memory and learning that are modified by experience.

“Our findings could also shed light on the diagnosis and treatment of conditions common to the adult aging brain, such as dementia and Alzheimer’s disease,” he said.