Posts tagged disorders
Articles and news from the latest research reports.
Brain discovery sheds light on link between vision and emotion
Neuroscientists have discovered a new area of the brain that is uniquely specialised for peripheral vision and could be targeted in future treatments for panic disorders and Alzheimer’s disease.
Published today in high impact journal Current Biology, researchers led by Dr Hsin-Hao Yu and Professor Marcello Rosa from Monash University’s Department of Physiology found that a brain area, known as prostriata, was specialised in detecting fast-moving objects in peripheral vision.
This area, located in a primitive part of the cerebral cortex, has characteristics unlike any other visual area described before, including a “direct line” of communication to brain areas controlling emotion and quick reactions.
Dr Yu said the discovery, identified during the development of the Monash Vision Group’s bionic eye, funded through the ARC Research in Bionic Vision Science and Technology Initiative, could lead to new treatments for panic disorders such as agoraphobia (fear of open spaces) and may extend into other medical areas including Alzheimer’s treatment.
“The brain is the most complex organ in the human body and perhaps the most remarkable. These findings change how we think of the brain in terms of how visual information is processed,” Dr Yu said.
“This area is likely to be hyperactive in panic disorder, with agoraphobia. This knowledge could lead to treatment options for the hyperactivity, and therefore sensitivity to such disorders, particularly the fear of open spaces.
“Correlation with previous studies also shows that prostriata is one of the first areas affected in Alzheimer’s disease. This knowledge helps to explain spatial disorientation and the tendency to fall, which are among the earliest signs of a problem associated with Alzheimer’s.”
Professor Rosa said this area had ultra-fast responses to visual stimuli, simultaneously broadcasting information to brain areas that control attention, emotional and motor reactions. This challenges current conceptions of how the brain processes visual information.
“This suggests a specialised brain circuit through which stimuli in peripheral vision can be fast-tracked to command quickly coordinated physical and emotional responses,” Professor Rosa said.
Childless Women With Fertility Problems at Higher Risk of Hospitalization for Psychiatric Disorders
ScienceDaily (July 2, 2012) — While many small studies have shown a relationship between infertility and psychological distress, reporting a high prevalence of anxiety, mood disorders and depressive symptoms, few have studied the psychological effect of childlessness on a large population basis. Now, based on the largest cohort of women with fertility problems compiled to date, Danish investigators have shown that women who remained childless after their first investigation for infertility had more hospitalisations for psychiatric disorders than women who had at least one child following their investigation.
The results of the study were presented July 1 at the annual meeting of ESHRE (European Society of Human Reproduction and Embryology) by Dr Birgitte Baldur-Felskov, an epidemiologist from the Danish Cancer Research Center in Copenhagen.
Most studies of this kind have been based on single clinics and self-reported psychological effects. This study, however, was a nationwide follow-up of 98,737 Danish women investigated for infertility between 1973 and 2008, who were then cross-linked via Denmark’s population-based registries to the Danish Psychiatric Central Registry. This provided information on hospitalisations for psychiatric disorders, which were divided into an inclusive group of “all mental disorders,” and six discharge sub-groups which comprised “alcohol and intoxicant abuse,” “schizophrenia and psychoses,” “affective disorders including depression,” “anxiety, adjustment and obsessive compulsive disorder,” “eating disorders,” and “other mental disorders.”
All women were followed from the date of their initial fertility investigation until the date of psychiatric event, date of emigration, date of death, date of hospitalisation or 31st December 2008, whichever came first. Such studies, said Dr Baldur-Felskov, could only be possible in somewhere like Denmark, where each citizen has a personal identification number which can be linked to any or all of the country’s diagnostic registries.
Results of the study showed that, over an average follow-up time of 12.6 years (representing 1,248,243 woman-years), 54% of the 98,737 women in the cohort did have a baby. Almost 5000 women from the entire cohort were hospitalised for a psychiatric disorder, the most common discharge diagnosis being “anxiety, adjustment and obsessive compulsive disorders” followed by “affective disorders including depression.”
However, those women who remained childless after their initial fertility investigation had a statistically significant (18%) higher risk of hospitalisations for all mental disorders than the women who went on to have a baby; the risk was also significantly greater for alcohol/substance abuse (by 103%), schizophrenia (by 47%) and other mental disorders (by 43%). The study also showed that childlessness increased the risk of eating disorders by 47%, although this was not statistically significant.
However, the most commonly seen discharge diagnosis in the entire cohort (anxiety, adjustment and obsessive compulsive disorders) was not affected by fertility status.
Commenting on the study’s results, Dr Baldur-Felskov said: “Our study showed that women who remained childless after fertility evaluation had an 18% higher risk of all mental disorders than the women who did have at least one baby. These higher risks were evident in alcohol and substance abuse, schizophrenia and eating disorders, although appeared lower in affective disorders including depression.
"The results suggest that failure to succeed after presenting for fertility investigation may be an important risk modifier for psychiatric disorders. This adds an important component to the counselling of women being investigated and treated for infertility. Specialists and other healthcare personnel working with infertile patients should also be sensitive to the potential for psychiatric disorders among this patient group."
Source: Science Daily
REM Sleep Disorder Doubles Risk of Mild Cognitive Impairment, Parkinson’s, Study Finds
ScienceDaily (Mar. 14, 2012) — People with symptoms suggesting rapid eye movement sleep behavior disorder, or RBD, have twice the risk of developing mild cognitive impairment (MCI) or Parkinson’s disease within four years of diagnosis with the sleep problem, compared with people without the disorder, a Mayo Clinic study has found.
The researchers published their findings recently in the Annals of Neurology.
One of the hallmarks of rapid eye movement (REM) sleep is a state of paralysis. In contrast, people with rapid eye movement sleep behavior disorder, appear to act out their dreams when they are in REM sleep. Researchers used the Mayo Sleep Questionnaire to diagnose probable RBD in people who were otherwise neurologically normal. Approximately 34 percent of people diagnosed with probable RBD developed MCI or Parkinson’s disease within four years of entering the study, a rate 2.2 times greater than those with normal rapid eye movement sleep.
"Understanding that certain patients are at greater risk for MCI or Parkinson’s disease will allow for early intervention, which is vital in the case of such disorders that destroy brain cells. Although we are still searching for effective treatments, our best chance of success is to identify and treat these disorders early, before cell death," says co-author Brad Boeve, M.D., a Mayo Clinic neurologist.
Previous studies of Mayo Clinic patients have shown that an estimated 45 percent of people who suffer from RBD will develop a neurodegenerative syndrome such as mild cognitive impairment or Parkinson’s disease within five years of diagnosis.
RBD, MCI and Parkinson’s Disease
"This study is the first to quantify the risk associated with probable RBD in average people, not clinical patients, and it shows that we can predict the onset of some neurodegenerative disorders simply by asking a few critical questions," says lead author Brendon P. Boot, M.D., a behavioral neurologist. Dr. Boot was at Mayo Clinic when the study was conducted. He is now at Harvard University.
- MCI is an intermediate stage between the expected cognitive decline of normal aging and the more pronounced decline of dementia. It involves problems with memory, language, thinking and judgment that are greater than typical age-related changes.
- An estimated 500,000 Americans suffer from Parkinson’s disease, which is characterized by tremor or shakiness, stiffness of the limbs and trunk, slowness of movement, and impaired balance and coordination.
Source: Science Daily