Super-sensory hearing?

The discovery of a previously unidentified hearing organ in the South American bushcrickets’ ear could pave the way for technological advancements in bio-inspired acoustic sensors research, including medical imaging and hearing aid development.

Researchers from the University of Bristol and University of Lincoln discovered the missing piece of the jigsaw in the understanding of the process of energy transformation in the ‘unconventional’ ears of the bushcrickets (or katydids).

Bushcrickets have four tympana (or ear drums) – two on each foreleg; but until now it has been unknown how the various organs connect in order for the insect to hear. As the tympana (a membrane which vibrates in reaction to sound) does not directly connect with the mechanoreceptors (sensory receptors), it was a mystery how sound was transmitted from air to the mechano-sensory cells.

Sponsored by the Human Frontiers Science Program (HFSP), the research was developed in the lab of Professor Daniel Robert, a Royal Society Fellow at the University of Bristol. Dr Fernando Montealegre-Z, who is now at the University of Lincoln’s School of Life Sciences, discovered a newly identified organ while carrying out research into how the bushcricket tubing system in the ear transports sound. The research focussed on the bushcricket Copiphora gorgonensis, a neotropical species from the National Park Gorgona in Colombia, an island in the Pacific. Results suggest that the bushcricket ear operates in a manner analogous to that of mammals. A paper detailing this remarkable new breakthrough is published in the journal, Science.

Reduced Cardiac Vagal Modulation Impacts on Cognitive Performance in Chronic Fatigue Syndrome

Background: Cognitive difficulties and autonomic dysfunction have been reported separately in patients with chronic fatigue syndrome (CFS). A role for heart rate variability (HRV) in cognitive flexibility has been demonstrated in healthy individuals, but this relationship has not as yet been examined in CFS. The objective of this study was to examine the relationship between HRV and cognitive performance in patients with CFS.

Methods: Participants were 30 patients with CFS and 40 healthy controls; the groups were matched for age, sex, education, body mass index, and hours of moderate exercise/week. Questionnaires were used to obtain relevant medical and demographic information, and assess current symptoms and functional impairment. Electrocardiograms, perceived fatigue/effort and performance data were recorded during cognitive tasks. Between–group differences in autonomic reactivity and associations with cognitive performance were analysed.

Results: Patients with CFS showed no deficits in performance accuracy, but were significantly slower than healthy controls. CFS was further characterized by low and unresponsive HRV; greater heart rate (HR) reactivity and prolonged HR-recovery after cognitive challenge. Fatigue levels, perceived effort and distress did not affect cognitive performance. HRV was consistently associated with performance indices and significantly predicted variance in cognitive outcomes.

Conclusions: These findings reveal for the first time an association between reduced cardiac vagal tone and cognitive impairment in CFS and confirm previous reports of diminished vagal activity.

Parkinson’s Disease Protein Causes Disease Spread and Neuron Death in Healthy Animals

Understanding how any disease progresses is one of the first and most important steps towards finding treatments to stop it. This has been the case for such brain-degenerating conditions as Alzheimer’s disease. Now, after several years of incremental study, researchers at the Perelman School of Medicine, University of Pennsylvania have been able to piece together important steps in how Parkinson’s disease (PD) spreads from cell to cell and leads to nerve cell death.

Their line of research also informs the general concept that this type of disease progression is a common pathway for such other neurodegenerative diseases as Alzheimer’s, Huntington’s, progressive supranuclear palsy, and possibly amyotrophic lateral sclerosis (ALS).

The Penn team found that injecting synthetic, misfolded and fibrillar α-Synuclein (α-Syn) – the PD disease protein — into the brains of normal, “wild-type” mice recapitulates the cascade of cellular demise seen in human PD patients.

Parkinson’s disease is characterized by abundant α-Syn clumps in neurons and the massive loss of midbrain dopamine-producing neurons. However, a cause-and-effect relationship between the formation of α-Syn clumps and neurodegeneration has been unclear.

In short, the Penn researchers found that, in healthy mice, a single injection of synthetic, misfolded α-Syn fibrils led to a cell-to-cell transmission of pathologic α-Syn proteins and the formation of Parkinson’s α-Syn clumps known as Lewy bodies in interconnected regions of the brain. Their findings appear in this week’s issue of Science. The team was led by senior author Virginia M.-Y Lee, PhD, director of the Center for Neurodegenerative Disease Research (CNDR) and professor of Pathology and Laboratory Medicine, and first author Kelvin C. Luk, PhD, research assistant professor in the CNDR.

When the going gets tough, the tough get… more relief from a placebo?

Are you good at coping when life gets tough? Do people call you a straight-shooter? Will you help others without expecting anything in return?

Those personality traits might do more than help you win a popularity contest. According to new University of Michigan-led neuroscience research, those qualities also might make you more likely to get pain relief from a placebo – a fake medicine.

And, the researchers show, it’s not just your mind telling you the sham drug is working or not. Your brain’s own natural painkiller chemicals may actually respond to the pain differently depending on your personality.

If you’re more of an angry, hostile type, they find, a placebo won’t do much for you.

For the first time, the new findings link specific, established personality traits with an individual’s susceptibility to the placebo effect from a sham medicine for pain. The researchers showed a significant link between certain personality traits and how much relief people said they felt when given the placebo – as well as the level of a specific chemical that their brains released.

The work, published online in the journal Neuropsychopharmacology, was done by a team of U-M Medical School researchers and their colleagues at the University of North Carolina and University of Maryland.

One neuron has huge impact on brain behaviour

Researchers from Queensland and the USA have made a unique discovery about how the brain computes sensory information.

The study by scientists at the Queensland Brain Institute (QBI) at The University of Queensland (UQ) and the Howard Hughes Medical Institute in the USA was conducted to better understand how circuits of nerve cells underlie behaviour.

Using advanced optical imaging in animal models, the research team was able to pinpoint a single neuron in the neocortex that signaled sensory behavior. This led to the discovery that active processes in its thin dendritic appendages are responsible for implementing the integration of sensory and motor signals.

“We have long known that active dendrites provide neurons with powerful processing capabilities,” says QBI’s Associate Professor Stephen Williams, who collaborated on the study. “However, little has been known about the role of neuronal dendrites in behaviourally related circuit computations. “We were pleasantly surprised to discover that the dendrites of nerve cells operate during behaviour to implement the integration of sensory and motor signals,” he said.

Such multi-modal integration enables the brain to perform at lightning speed, allowing animals to react to their environment in relation to existing knowledge. The paper, titled ‘Nonlinear dendritic integration of sensory and motor input during an active sensing task’ was published in the prestigious journal, Nature.

This is Your Brain on Freestyle Rap: NIDCD Study Reveals Characteristic Brain Patterns of Lyrical Improvisation

Researchers in the voice, speech, and language branch of the National Institute on Deafness and Other Communication Disorders (NIDCD) at the National Institutes of Health (NIH) have used functional magnetic resonance imaging to study the brain activity of rappers when they are “freestyling”—spontaneously improvising lyrics in real time. The findings, published online in the November 15 issue of the journal Scientific Reports, reveal that this form of vocal improvisation is associated with a unique functional reallocation of brain activity in the prefrontal cortex and proposes a novel neural network that appears to be intimately involved in improvisatory and creative endeavors. 

The researchers, led by Siyuan Liu, Ph.D., scanned the brains of 12 freestyle rap artists (who had at least 5 years of rapping experience) while they performed two tasks using an identical 8-bar musical track. For the first task, they improvised rhyming lyrics and rhythmic patterns guided only by the beat. In the second task, they performed a well-rehearsed set of lyrics.

During freestyle rapping, the researchers observed increases in brain activity in the medial prefrontal cortex, a brain region responsible for motivation of thought and action, but decreased activity in dorsolateral prefrontal regions that normally play a supervisory or monitoring role. Like an experienced parent who knows when to lay down the law and when to look the other way, these shifts in brain function may facilitate the free expression of thoughts and words without the usual neural constraints. 

Freestyling also increased brain activity in the perisylvian system (involved in language production), the amygdala (an area of the brain linked to emotion), and cingulate motor areas, suggesting that improvisation engages a brain network that links motivation, language, mood, and action. Further studies of this network in other art forms that involve the innovative use of language, such as poetry and storytelling, could offer more insights into the initial, improvisatory phase of the creative process.

Uncommon Features of Einstein’s Brain Might Explain His Remarkable Cognitive Abilities

Portions of Albert Einstein’s brain have been found to be unlike those of most people and could be related to his extraordinary cognitive abilities, according to a new study led by Florida State University evolutionary anthropologist Dean Falk.

Falk, along with colleagues Frederick E. Lepore of the Robert Wood Johnson Medical School and Adrianne Noe, director of the National Museum of Health and Medicine, describe for the first time the entire cerebral cortex of Einstein’s brain from an examination of 14 recently discovered photographs. The researchers compared Einstein’s brain to 85 “normal” human brains and, in light of current functional imaging studies, interpreted its unusual features.

“Although the overall size and asymmetrical shape of Einstein’s brain were normal, the prefrontal, somatosensory, primary motor, parietal, temporal and occipital cortices were extraordinary,” said Falk, the Hale G. Smith Professor of Anthropology at Florida State. “These may have provided the neurological underpinnings for some of his visuospatial and mathematical abilities, for instance.”

The study, “The Cerebral Cortex of Albert Einstein: A Description and Preliminary Analysis of Unpublished Photographs,” was published in the journal Brain.

Please amputate this leg: it’s not mine

This wasn’t the first time that David had tried to amputate his leg. When he was just out of college, he’d tried to do it using a tourniquet fashioned out of an old sock and strong baling twine. David (not his real name) locked himself in his bedroom at his parents’ house, his bound leg propped up against the wall to prevent blood from flowing into it. After two hours the pain was unbearable, and fear sapped his will.

Undoing a tourniquet that has starved a limb of blood can be fatal: injured muscles downstream of the blockage flood the body with toxins, causing the kidneys to fail. Even so, David released the tourniquet himself; it was just as well that he hadn’t mastered the art of tying one.

Failure did not lessen David’s desire to be rid of the leg. It began to consume him, to dominate his awareness. The leg was always there as a foreign body, an impostor, an intrusion.

He spent every waking moment imagining freedom from the leg. He’d stand on his “good” leg, trying not to put any weight on the bad one. At home, he’d hop around. While sitting, he’d often push the leg to one side. The leg just wasn’t his. He began to blame it for keeping him single; but living alone in a small suburban townhouse, afraid to socialise and struggling to form relationships, David was unwilling to let anyone know of his singular fixation.

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Insects change the way they communicate when drowned out by man-made noises

Birds and frogs do it, even whales have been known to do it. Now scientists have for the first time shown that insects also change the way they sing to one another when drowned out by man-made noises.

Click HERE to listen to a grasshopper battling traffic noise

Grasshoppers living next to a main road respond to the increased background volume of passing traffic by adjusting their summer courtship songs, scientists have discovered.

In order to make themselves heard above the low-rumble noise pollution of moving vehicles, male bow-winged grasshoppers of central Europe alter the pitch of their songs’ lower notes so that they rise to a mini-crescendo, the scientists found.

“Bow-winged grasshoppers produce songs that include low and high frequency components,” said Ulrike Lampe of the University of Bielefeld in Germany, who led the study published in the journal Functional Ecology.

“We found that grasshoppers from noisy habitats boost the volume of the lower-frequency part of their song, which makes sense since road noise can mask signals in this part of the frequency spectrum,” Dr Lampe said.