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Showing posts from September, 2017

Childhood maltreatment may change brain's response to threat

The amygdala and a closely related region called the bed nucleus of the stria terminalis (BNST) are both activated in response to a threat, but it is unclear how these regions orchestrate defensive responses in humans. Floris Klumpers and colleagues found that anticipation of an uncomfortable but harmless electrical shock was associated with increased activity in BNST , which is strongly connected with other brain regions that may be involved in deciding how to respond to a distant threat. In contrast, the shock itself was associated with increased activity in the amygdala, which maintains stronger connections with lower brain regions that may facilitate immediate and involuntary responses to acute danger, such as increased heart rate. Finally, the authors found that participants in one sample who reported greater childhood maltreatment (primarily emotional abuse and neglect rather than physical and sexual abuse) exhibited increased amygdala activity during shock anticipation. Thi...

Explaining bursts of activity in brains of preterm babies

In a new study published in  eLife  and funded by the National Institute for Health Research and the Medical Research Council, the researchers found that a specific brain region called the insula plays a major role in the generation of the spontaneous neuronal bursts. The researchers say the spontaneous brain activity is essential to strengthen brain connections which will serve as ' scaffolding ' that will then develop further with life experience. Other studies have found that infants whose brains don't display this activity are more likely to develop cerebral palsy or have poor cognitive skills later in life. "While we don't yet know what causes these neuronal bursts, we know that in healthy babies, they are present preterm and disappear at full term. It's a bad sign if they are absent in preterm or present still after full term," said one of the study's lead authors, Dr Lorenzo Fabrizi (UCL Biosciences). "The brain of a preterm baby is ...

Reversing the negative effects of adolescent marijuana use

"What is important about this study is that not only have we identified a specific mechanism in the prefrontal cortex for some of the mental health risks associated with adolescent marijuana use, but we have also identified a mechanism to reverse those risks," said Steven Laviolette, professor at Western's Schulich School of Medicine & Dentistry. In a study published online today in  Scientific Reports  the researchers demonstrate that adolescent THC exposure modulates the activity of a neurotransmitter called GABA in the prefrontal cortex region of the brain. The team, led by Laviolette and post-doctoral fellow Justine Renard, looked specifically at GABA because of its previously shown clinical association with schizophrenia. "GABA is an inhibitory neurotransmitter and plays a crucial role in regulating the excitatory activity in the frontal cortex, so if you have less GABA, your neuronal systems become hyperactive leading to behavioural changes consistent...

Brain activity between seizures informs potential treatment for childhood absence epilepsy

https://www.mymedistore.com/ Absence seizures cause a short period of "blanking out" or staring into space, due to brief abnormal electrical activity in the brain. In this new study, even after the seizures in the mice were treated, the abnormality that was previously seen between seizures persisted. This may provide a potential explanation for why some children with absence epilepsy may have continued deficits in cognitive performance, despite successful treatment of their seizures. EEG, a test that measures electrical activity in the brain, has thus far been primarily used to detect seizures, rather than identifying cognitive impairment. This study suggests that looking at EEG activity between seizures could help physicians diagnose and monitor cognitive and other attentional deficits in epilepsy. Jeffrey Noebels and his team at Baylor College of Medicine in Houston, Texas used two genetic mouse models of absence epilepsy and compared them to unaffected mice. They an...

Memory decline after head injury may be prevented by slowing brain cell growth

In the September issue of  Stem Cell Reports , Viji Santhakumar, associate professor in the department of Pharmacology, Physiology and Neuroscience, and her colleagues, challenge the prevailing assumption by scientists in the field that excessive neurogenesis (the birth of new brain cells) after injury is advantageous. "There is an initial increase in birth of new neurons after a brain injury but within weeks, there is a dramatic decrease in the normal rate at which neurons are born, depleting brain cells that under normal circumstances should be there to replace damaged cells and repair the brain's network," said Santhakumar. "The excess new neurons lead to epileptic seizures and could contribute to cognitive decline" In the United States an estimated 1.7milllion people sustain a TBI each year, making the condition a major cause of death and disability. Symptoms can include impaired thinking or memory, personality changes and depression and vision and hea...

Why bad sleep doesn't always lead to depression

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Larger exercise within the ventral striatum, the mind's reward middle, might buffer some people in opposition to the unfavorable psychological well being results of poor sleep. Credit score: Annchen R. Knodt, Duke College Poor sleep is each a threat issue, and a typical symptom, of despair. However not everybody who tosses and turns at evening turns into depressed. People whose brains are extra attuned to rewards could also be shielded from the unfavorable psychological well being results of poor sleep, says a brand new research by Duke College neuroscientists. The researchers discovered that faculty college students with poor high quality sleep have been much less more likely to have signs of despair if additionally they had increased exercise in a reward-sensitive area of the mind. "This helps us start to grasp why some persons are extra more likely to expertise despair once they have issues with sleep," ment...

Sex, aggression controlled separately in female animal brains, but overlap in male brains

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Diagram of mouse mind (far left) and the ventrolateral a part of the ventromedial hypothalamus, or VMHvl, which controls for aggression in each male -- and feminine -- mice. Center picture reveals VMHvl cells in feminine mind, with cells lively in mating (in blue) situated round border, whereas these within the male mind (far proper) are dispersed. Cells lively in combating (in crimson) are situated extra within the middle of the feminine VMHvl , however not so in male mice. Credit score: Courtesy of Nature Neuroscience Mind constructions that management sexual and aggressive habits in mice are wired in a different way in females than in males. This the discovering of a research led by scientists at NYU Faculty of Drugs and printed on-line Sept. 18 in  Nature Neuroscience . Particularly, researchers discovered that, whereas management of aggressive habits resides in similar mind area in feminine and male mice, sure teams of ...

Owners of seriously ill pets at risk of stress, anxiety and depressive symptoms

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Caring for a sick or dying pet is usually a severe emotional burden. Credit score: © tuaindeed / Fotolia Homeowners of severely or terminally in poor health pets usually tend to undergo with stress and signs of melancholy and nervousness, in addition to poorer high quality of life, in contrast with house owners of wholesome animals, finds a examine. This 'caregiver burden' might also result in elevated veterinarian stress, say the authors. Analysis on human caregiving describes ' caregiver burden' as a response to issues and challenges encountered whereas offering casual take care of a sick member of the family. However little is understood in regards to the affect of caregiver burden on house owners of animals with power or terminal ailments -- and the veterinarians who take care of them. So a group of researchers, led by Mary Beth Spitznagel at Kent State College in Ohio, got down to assess caregiver burden and...

The brain at work: Spotting half-hidden objects

The human (and non-human) primate brain is remarkable in recognizing objects when the view is nearly blocked. This skill let our ancient ancestors find food and avoid danger. It continues to be critical to making sense of our surroundings. UW Medicine scientists are conducting research to discover ways that the brain operates when figuring out shapes, from those that are completely visible to those that are mostly hidden. Although computers can beat the world's best chess players, scientists have not yet designed artificial intelligence that performs as well as the average person in distinguishing shapes that are semi-obscured. Studies of signals generated by the brain are helping to fill in the picture of what goes on when looking at, then trying to recognize, shapes. Such research is also showing why attempts have failed to mechanically replicate the ability of humans and primates to identify partially hidden objects. The most recent results of this work are published ...

Overcoming the brain's fortress-like barrier

The brain is protected by the near-impermeable blood brain barrier, a fortress which protects the brain but which also prevents the treatment of brain diseases, including brain tumours. Dr Zaynah Maherally and team at the University of Portsmouth have developed a model that mimics the blood brain barrier, which could pave the way for better, more efficient and reliable tests of drugs to treat brain diseases. ,p>The model, the result of slow painstaking research started in 2007, is published in the  FASEB Journal . Dr Maherally said: "The blood brain barrier is strikingly complex and notoriously difficult for scientists to breach. Its role, to protect the brain, makes it difficult for most drugs to make their way into the brain to treat brain tumours. "It is a dynamic structural, physiological and biochemical fortification that, in essence, protects the brain by providing multiple layers of armour, stopping molecules from entering the brain. It's highly select...