joi, 23 iulie 2009

Patients with depression frequently suffer from medically unexplained pain

Pain symptoms that cannot be attributed, or at least not fully attributed, to an organic origin are more frequently and more severely experienced by patients with depression than by those without. "It is the case that women are much more frequently affected by depression and also by so-called somatoform pain disorder than men," explains Dirk Frieser, psychologist at the Institute of Psychology at Johannes Gutenberg University Mainz, Germany.

For the purposes of his doctoral dissertation, Frieser and fellow psychologist Stephanie Körber questioned 308 patients attending two practices of general practitioners in Mainz. Patients were asked about their state of health and their pain symptoms, but also about their anxieties with regard to illness, how they react when ill, what social support they receive, and what psychological stress they experience, together with many other aspects. Subsequently, the pain symptoms reported by the patients were evaluated by their doctors. Somatoform symptoms, i.e., symptoms that cannot or not fully be explained in medical terms, are an astonishingly widespread phenomenon.

According to Frieser "up to 80 percent of the symptoms reported in GP practices are somatoform. However, this does not mean that patients are simply 'imagining' that they have these symptoms." Somatoform symptoms are very real; they impair quality of life, and can also cause clinically relevant disorders that may require psychological treatment, such as cognitive behavioral therapy. Somatoform disorders, which are often popularly dismissed as 'hypochondria, ' frequently not only involve pain symptoms but also other symptoms such as dizziness, sensations of hypersensitivity in various regions of the body, and even fatigue or exhaustion.

What is important, according to Frieser, is that not everyone who has somatoform symptoms is diagnosed as having a somatoform disorder. The extent to which a patient's quality of life is impaired and the severity of the psychological problems they experience are the determining factors here. Taking as their starting point the survey of GP practices in Mainz under the supervision of Professor Wolfgang Hiller of Mainz University, Frieser and Körber decided to investigate what influence depression has on the pain experience of patients and to determine whether this differs if the pain is of clinical origin and if the pain has no medically identifiable cause. "The results indicate that there is a significantly higher occurrence of somatoform pain in various body regions in patients with existing depression or who suffered depression in the previous 12 months than in patients without depression."

According to Frieser then, it is possible that patients who report to their doctors with multiple pain symptoms that cannot be explained in clinical terms are very probably suffering from a depressive disorder requiring treatment. In cases of major depression, the affected patients often exhibit dejection, despair, swings in appetite and body weight, insomnia or an increased need for sleep, tiredness, lack of energy, and psychomotor disturbances. These patients not infrequently also consider committing suicide. Short term mood swings with a duration of less than two weeks are not considered characteristic elements of this disorder.

The results of the GP survey in Mainz underline the importance of the correct classification and evaluation of pain symptoms for healthcare services; the general practitioners concluded that pain was somatoform in 73 percent of cases, and could be fully explained in medical terms in only 27 percent of cases. Where the pain is attributable to an organic cause, it is irrelevant whether the patient has depression or not: The frequency, duration, and the debilitating effect of the pain are roughly equivalent in both patient groups.

Source: University Mainz http://www.physorg. com/news16694352 5.html

Healthy, despite being born with half a brain

Scientists reveal secret of girl with 'all seeing eye' July 20th, 2009 in Medicine & Health /

Scientists have discovered how a 10-year-old girl born with half a brain is able to see normally through one eye. The youngster, from Germany, has both fields of vision in one eye and is the only known case of its kind in the world.

University of Glasgow researchers used Functional Magnetic Resonance Imaging (fMRI) to reveal how the girl's brain had rewired itself in order to process information from the right and left visual fields in spite of her not having a whole brain. The right hemisphere in the girl's brain failed to develop in the womb. Normally, the left and right fields of vision are processed and mapped by opposite sides of the brain, but scans on the German girl showed that retinal nerve fibres that should go to the right hemisphere of the brain diverted to the left. Further, the researchers found that within the visual cortex of the left hemisphere, which creates an internal map of the right field of vision, 'islands' had been formed within it to specifically deal with, and map out, the left visual field in the absence of the right hemisphere.

Dr Lars Muckli of the Centre for Cognitive Neuroimaging in the Department of Psychology, who led the study, said: "This study has revealed the surprising flexibility of the brain when it comes to self-organising mechanisms for forming visual maps. "The brain has amazing plasticity but we were quite astonished to see just how well the single hemisphere of the brain in this girl has adapted to compensate for the missing half. "Despite lacking one hemisphere, the girl has normal psychological function and is perfectly capable of living a normal and fulfilling life. She is witty, charming and intelligent. "

An MRI scan clearly showing only one hemisphere of the brain. The girl's underdeveloped brain was discovered when, aged three, she underwent an MRI scan after suffering seizures of brief involuntary twitching on her left side. Apart from the seizures, which were successfully treated and slight weakness on her left side (hemiparesis) , the girl had a normal developmental and medical history, attending regular school and taking part in activities such as roller-skating. In other cases, where patients have half of the brain removed (hemispherectomy) , to treat severe epilepsy for example, one field of vision is lost in both eyes - i.e. they see only objects on the left or right side of their vision.

In the case of the German girl, her left and right field vision is almost perfect in one eye. Visual information is gathered by the retina at the back of the eye and images are inverted when they pass through the lens of the pupil so that images in your left field of vision are received on the right side of the retina, and images from the right are received on the left. The part of the retina closest to your nose is called the nasal retina, while the other half is called the temporal retina, as it is next to the temples of the head, and both halves have separate nerve fibres which transmit the information received. Normally, the nerve fibres from the nasal retina cross over in a part of the brain called the optic chiasma and are processed by the hemisphere on the opposite side.

The nerve fibres from the temporal retina remain in the same hemisphere, so this means that the left and right visual fields at processed by opposite sides of the brain. However, in this case, the nasal retinal nerve had connected to the left brain hemisphere. The scientists believe the right hemisphere of the girl's brain stopped developing early in the womb and that when the developing optic nerves reached the optic chiasma, the chemical cues that would normally guide the left eye nasal retinal nerve to the right hemisphere were no longer present and so the nerve was drawn to the left. This implies that there are no molecular repressors to prevent nasal retinal nerve fibres from entering the same hemisphere. Dr Muckli added: "If we could understand the powerful algorithms the brain uses to rewire itself and extract those algorithms together with the general algorithms that the brain uses to process information, they could be applied to computers and could result in a huge advance in artificial intelligence. "

The study, which was begun by Dr Muckli at the Max Planck Institute for Brain Research in Germany and involved colleagues at the Institute of Medical Psychology at Goethe-University, Frankfurt-am- Main, is published in the 'Proceedings of the National Academy of Science USA'.

Provided by University of Glasgow http://www.physorg. com/news16732481 3.html

joi, 16 iulie 2009

ADHD genes found, known to play roles in neurodevelopment

Pediatric researchers have identified hundreds of gene variations that occur more frequently in children with attention-deficit hyperactivity disorder (ADHD) than in children without ADHD. Many of those genes were already known to be important for learning, behavior, brain function and neurodevelopment, but had not been previously associated with ADHD.

"Because the gene alterations we found are involved in the development of the nervous system, they may eventually guide researchers to better targets in designing early intervention for children with ," said lead author Josephine Elia, M.D., a psychiatrist and ADHD expert at The Children's Hospital of Philadelphia.

The study appeared in the Journal of Molecular Psychiatry.

Unlike changes to single DNA bases, called SNPs or "snips," the alterations examined in the current study are broader changes in structure. Called copy number variations (CNVs), they are missing or repeated stretches of DNA. CNVs have recently been found to play significant roles in many diseases, including autism and schizophrenia Everyone has CNVs in their DNA, but not all of the variations occur in locations that affect the function of a gene. The current study is the first to investigate the role of CNVs in ADHD.

Individually, each CNV may be rare, but taken together, a combination of changes in crucial regions may interact to raise an individual's risk for a specific disease. "When we began this study in 2003, we expected to find a handful of genes that predispose a child to ADHD," said study co-leader Peter S. White, Ph.D., a molecular geneticist and director of the Center for Biomedical Informatics at Children's Hospital. "Instead, there may be hundreds of genes involved, only some of which are changed in each person. But if those genes act on similar pathways, you may end up with a similar result—ADHD. This may also help to explain why children with ADHD often present clinically with slightly different symptoms."

ADHD is the most common neuropsychiatric disorder in children, affecting an estimated 1 in 20 children worldwide. It may include hyperactive behavior, impulsivity and inattentive symptoms, with impaired skills in planning, organizing, and maintaining focus. Its cause is unknown, but it is known from family studies to be strongly influenced by genetics.

Drawing on DNA samples from the Children's Hospital pediatric network, the researchers analyzed genomes from 335 ADHD patients and their families, compared to more than 2,000 unrelated healthy children. The team used highly automated gene-analyzing technology at the Center for Applied Genomics at Children's Hospital, directed by Hakon Hakonarson, M.D., Ph.D., a co-leader of this study.

The study team found a similar quantity of CNVs in both groups. However, distinct patterns emerged. Among 222 inherited CNVs found in ADHD families but not in healthy subjects, a significant number were in genes previously identified in other neurodevelopmental disorders, including autism, schizophrenia and Tourette syndrome. The CNVs found in ADHD families also altered genes important in psychological and neurological functions such as learning, behavior, synaptic transmission and nervous system development.

"We took a systems biology approach, grouping genes into groups with common functions," said White. "We found that the sets of genes more likely to be changed in ADHD patients and families affected functions that made sense biologically." For instance, said White, the team found four deletions of DNA in a gene recently linked to restless legs syndrome, a type of sleep disorder common in adults with ADHD.

Another deletion occurred in a gene for a glutamate receptor. Glutamate is a neurotransmitter, a protein that carries signals in the brain. While ADHD medications act on dopamine and serotonin, which are also neurotransmitters, this new finding may suggest an important role for glutamate as well, at least for some ADHD patients.

"As we delve into the genetics of very complex diseases such as ADHD, we find many contributing genes, often differing from one family to another," added White. "Studying the functions of different genes allows us to identify biological pathways that may be involved in this neuropsychiatric disorder."

Some of the biological pathways involved in ADHD may also be common to other neurological conditions, say the researchers. Likewise, there is some overlap among the CNVs found in ADHD that also occur in autism, schizophrenia and other neurological disorders. This overlap was not surprising, said Elia, because ADHD patients frequently also have one of more of these disorders. However, as researchers learn more about specific genes in neurological conditions, the hope is that researchers might in the future personalize treatments to a patient's own genetic profile, to achieve more targeted, specific therapies.

Elia and White stressed that much further work must be done before genetic findings lead to ADHD treatments.
More information: Elia et al, "Rare Structural Variants Found in Are Preferentially Associated with Neurodevelopmental ," Molecular Psychiatry, published online, June 23, 2009.

Source: Children's Hospital of Philadelphia

More Gene Mutations Linked To Autism Risk

ScienceDaily (June 28, 2009) — More pieces in the complex autism inheritance puzzle are emerging in the latest study from a research team including geneticists from The Children's Hospital of Philadelphia, the University of Pennsylvania School of Medicine and several collaborating institutions. This study identified 27 different genetic regions where rare copy number variations – missing or extra copies of DNA segments – were found in the genes of children with autism spectrum disorders (ASDs), but not in the healthy controls.

The complex combination of multiple genetic duplications and deletions is thought to interfere with gene function, which can disrupt the production of proteins necessary for normal neurological development.

"We focused on changes in the exons of DNA—protein-coding areas in which deletions or duplications are more likely to directly disrupt biological functions," said study leader Hakon Hakonarson, M.D., Ph.D., director of the Center for Applied Genomics at The Children's Hospital of Philadelphia and associate professor of Pediatrics at the University of Pennsylvania School of Medicine. "We identified additional autism susceptibility genes, many of which, as we previously found, belong to the neuronal cell adhesion molecule family involved in the development of brain circuitry in early childhood." He added that the team discovered many "private" gene mutations, those found only in one or a few individuals or families—an indication of genetic complexity, in which many different gene changes may contribute to an autism spectrum disorder.

"We are finding that both inherited and new, or de novo, genetic mutations are scattered throughout the genome and we suspect that different combinations of these variations contribute to autism susceptibility," said Maja Bucan, Ph.D., professor of Genetics at the University of Pennsylvania School of Medicine and Chair of the Steering committee for Autism Speaks' Autism Genetic Resource Exchange (AGRE). "We are grateful to families of children with autism spectrum disorders for their willingness to participate in genetic studies because family-based studies have many advantages. We have learned a lot both from genetic analyses of children with autism as well as analyses of their patents and their unaffected siblings."

The researchers compared genetic samples of 3,832 individuals from 912 families with multiple children with ASDs from the AGRE cohort against genetic samples of 1,070 disease-free children from The Children's Hospital of Philadelphia. This study also uncovered two novel genes in which variations were found, BZRAP1 and MDGA2 – thought to be important in synaptic function and neurological development, respectively. Interestingly, key variants of these genes were transmitted in some, but not all, of the affected individuals in families.

By further refining the genetic landscape of ASDs, the current study expands the findings of two large autism gene studies published in April, led by Hakonarson and co-authored by Gerard Schellenberg, Ph.D., professor of Pathology and Laboratory Medicine at the University of Pennsylvania School of Medicine, Bucan and others. One study was the first to report common gene variants in ASDs. The other identified copy number variants that raise the risk of having an ASD. Both studies found gene changes on two biological pathways with crucial roles in early central nervous system development. Hakonarson and Bucan said the latest findings reinforce the view that multiple gene variants, both common and rare, may be interacting to cause the heterogeneous group of disorders included under autism spectrum disorders.

Children With Autism Need To Be Taught In Smaller Groups, Experts Argue

ScienceDaily (July 4, 2009) — Since the 1970s, there has been much debate surrounding the fact that individuals with autism have difficulty in understanding speech in situations where there is background speech or noise.

At the annual meeting of the International Multisensory Research Forum (June 29th – July 2nd) being held at The City College of New York (CCNY), neuroscientists argue in favor of smaller class sizes for children with autism.

Speaking at the conference, Dr. John J. Foxe, Professor of Neuroscience at CCNY said: “Sensory integration dysfunction has long been speculated to be a core component of autism spectrum disorder (ASD) but there has been precious little hard empirical evidence to support this notion. Viewing a speaker’s articulatory movements can greatly improve a listener’s ability to understand spoken words, and this is especially the case under noisy environmental conditions.”

“These results are the first of their kind to verify that children with autism have substantial difficulties in these situations, and this has major implications for how we go about teaching these children in the classroom,” he continued. “Children with autism may become distressed in large classroom settings simply because they are unable to understand basic speech if the environment is sufficiently noisy.

“We should start to pay attention to the need for smaller numbers in the classroom and we need to carefully control the levels of background noise that these kids are exposed to. Imagine how frustrating it must be to sit in a classroom without being able to properly understand what the teacher or your classmates are saying to you.

“Being able to detect speech in noise plays a vital role in how we communicate with each other because our listening environments are almost never quiet. Even the hum of air conditioners or fans that we can easily ignore may adversely impact these children’s ability to understand speech in the classroom.

“Our data show that the multisensory speech system develops relatively slowly across the childhood years and that considerable tuning of this system continues to occur even into early adolescence. Our data suggest that children with Autism lag almost 5 years behind typically developing children in this crucial multisensory ability.”

Professor Foxe concluded that further studies may result in advances in the understanding of ASD and the communication abilities of individuals with autism by identifying the neural mechanisms that are at the root of these multisensory deficits. This will be an important step if viable intervention and training strategies are to be developed.

marți, 14 iulie 2009

Tulburarile de pe Axa I, conform DSM-IV-TR

M-am gandit ca este utila o viziune de ansamblu asupra clasificarii tulburarilor psihologice, din perspectiva unuia dintre cele mai cunoscute manuale de diagnostic, folosit de psihiatri si psihologi, DSM-IV-TR. Aici voi enumera doar cele mai importante tulburari, urmand ca in postarile viitoare sa ofer informatii despre unele dintre ele.

Asadar, cele mai tulburarile incadrate in Axa I (Tulbularile clinice si alte tulburari care se afla in centrul atentiei clinice) sunt:

- Tulburarile diagnosticate pentru prima data in perioada de sugar, copilarie sau adolescenta (excluzand retardarea mentala):
* tulburarile de invatare (dislexia, discalculia, disgrafia);
* tulburarea aptitudinilor motorii;
* tulburarile de comunicare (tulburarea de limbaj expresiv, mixta, fonologica, balbismul);
* tulburarile de dezvoltare pervaziva (tulburarea autista, Rett, tulburarea dezintegrativa a copilariei, Asperger);
* deficitul de atentie si tulburarile de comportament disruptiv (ADHD, tulburarea de conduita, tulburarea opozitionismului provocator);
* tulburarile alimentare si de comportament alimentar ale perioadei de sugar sau micii copilarii: pica, ruminatia, tulburarea de alimentare a perioadei de sugar sau a micii copilarii:
* ticurile;
* tulburarile de eliminare: enurezis si encoprezis;
* altele: anxietatea de separare, mutismul electiv, tulburarea reactiva de atasament, tulburarea de miscare stereotipa.

- Deliriumul, dementa, tulburarile amnestice si alte tulburari cognitive.

- Tulburarile in legatura cu o substanta.

- Schizofrenia si alte tulburari psihotice.

- Tulburarile afective (tulburarile depresive si bipolare).

- Tulburarile anxioase (tulburarea de panica, fobiile, tulburarea obsesiv-compulsiva, tulburarea de stres posttraumatic, tulburarea acuta de stres, tulburarea de tip anxietate generalizata).

- Tulburarile somatoforme (tulburarea de somatizare, de conversie, algica, hipocondria, tulburarea dismorfica corporala).

-Tulburarile factice.

- Tulburarile disociative (amnezia disociativa, fuga disociativa, tulburarea de identitate disociativa, tulburarea de depersonalizare).

- Tulburarile sexuale si de identitate sexuala (disfunctiile sexuale, parafiliile si tulburarile de identitate sexuala).

- Tulburarile de comportament alimentar (anorexia nervosa si bulimia nervosa).

- Tulburarile de somn (dissomnii si parasomnii).

- Tulburarile controlului impulsului neclasificate in alta parte (tulburarea exploziva intermitenta, cleptomania, piromania, jocul de sansa patologic, tricotilomania).

- Tulburarile de adaptare.

Informatiile au fost preluate din DSM-IV-TR, publicat de Asociatia Psihiatrilor Liberi din Romania, Bucuresti, 2003.