Category Archives: Articole stiintifice

Jurnalul International de Educatie Speciala

Gasiti articolele full-text la adresa de mai jos:

http://www.internationaljournalofspecialeducation.com/issues.cfm

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Autismul si procesarea cuvintelor familiare

Reactiile creierului la cuvinte sunt un predictor al progreselor in
dezvoltarea copiilor cu autism

(articol tradus partial)

Conform unui nou studiu, pattern-ul de raspunsuri ale creierului la cuvinte (la copiii de 2 ani cu tulburare de spectru autist) este un predictor al abilitatilor lingvistice, cognitive si adaptative de la varstele de 4 si 6 ani.

Rezultatele acestei cercetari, publicate in data de 29 mai in PLOS ONE, sunt primele care arata ca un marker cerebral poate prezice abilitatile viitoare ale copiilor cu autism.

“Acest lucru este valabil la 4 ani dupa testarea initiala, indiferent de tipul de tratament de care au beneficiat copiii”, a spus Patricia Kuhl, co-director al Institutului pentru Invatare si Stiintele ale creierului, din cadrul Universitatii Washington.

Douazeci si patru de copii cu autism si 20 copii fara autism, au ascultat o multime de cuvinte familiare si non-familiare in timp ce purtau pe cap o casca cu senzori. Acei senzori au masurat raspunsurile creierului in momentul in care copiii auzeau cuvintele[…].

Apoi, cercetatorii au impartit copiii cu autism in doua grupuri, pe baza severitatii afectarii sociale si au studiat raspunsurile creierului. Copiii cu simptome mai putin severe au inregistrat raspunsuri cerebrale similare cu ale copiilor cu dezvoltare tipica; adica au reactionat puternic la cuvinte familiare (s-a activat aria limbajului localizata in regiunea temporo-parietala din partea stanga a creierului).

Acest fapt ne sugereaza urmatorul lucru: creierul copiilor cu simptome mai putin severe poate procesa cuvintele in maniera asemanatoare cu cel al copiilor fara autism.

Prin contrast, copiii cu afectare sociala severa au inregistrat raspunsuri cerebrale in emisfera dreapta, fenomen care nu a fost observat la copiii cu dezvoltare tipica.[…]

Cercetatorii au evaluat abilitatile cognitive, sociale, emotionale si de limbaj ale copiilor la 2, 4 si la 6 ani. Copiii cu autism care au participat la studiu au beneficiat de tratament intensiv si, per ansamblu, au obtinut scoruri mai bune la testele de comportament. Dar progresele pe toate ariile de dezvoltare au variat foarte mult: cu cat creierul copilului a reactionat mai puternic la cuvinte familiare la varsta de 2 ani, cu atat s-au vazut mai multe progrese la varsta de 6 ani. […]

“Invatarea sociala este una dintre trasaturile definitorii ale omului” spune Kuhl. “Daca creierul tau poate invata de la alti oameni intr-un context social, inseamna ca ai capacitatea de a invata aproape orice.”

Cercetatoarea spera ca aceasta descoperire va conduce la masuratori cerebrale  care sa poata fi folosite cu copiii de 12 luni (sau mai mici) pentru a-i identifica pe cei cu risc de a avea autism. […]

Gasiti articolul original aici:
http://www.sciencedaily.com/releases/2013/05/130529190724.htm

Pivotal response training si functionarea cerebrala la copiii cu autism

http://www.sciencedaily.com/releases/2013/02/130214120618.htm

 Using functional magnetic resonance imaging (fMRI) for before-and-after analysis, a team of researchers including a UC Santa Barbara graduate student discovered positive changes in brain activity in children with autism who received a particular type of behavioral therapy.

Work completed at Yale University’s Child Study Center used fMRI as the tool for measuring the impact of Pivotal Response Treatment (PRT) — therapy pioneered at UCSB by Lynn Koegel, clinical director of the Koegel Autism Center — on both lower- and higher-functioning children with autism receiving PRT for the first time. fMRI allows researchers to see what areas of the brain are active while processing certain stimuli — in this case human motion. Comparing pre- and post-therapy data from the fMRI scans of their 5-year-old subjects, the researchers saw marked — and remarkable — changes in how the children were processing the stimuli. Findings from their study, “Neural Mechanisms of Improvements in Social Motivation After Pivotal Response Treatment,” are published in a recent issue of theJournal of Autism and Developmental Disorders.

“The cool thing that we found was that these kids showed increased activation in regions of the brain utilized by typically developing kids,” explained Avery C. Voos, first-year graduate student at the UCSB-based Koegel Autism Center, and one of the lead authors of the Yale study. “After four months of treatment, they’re starting to use brain regions that typically developing kids are using to process social stimuli.

“We can say that we have shifted the way these children are processing low-level social stimuli, and that’s what we want,” she added. “There’s a social deficit in autism, so any improvement toward social interaction really helps with development. That’s what makes this very exciting, and it speaks to the promise and success of PRT.”

A targeted technique meant to improve social engagement among children with autism spectrum disorders, PRT forgoes the focus on specific skills, like block-building, to concentrate instead on so-called “pivotal areas,” such as motivation, in hopes of inducing a cascading effect with similar impact across multiple areas.

“For instance, if you’re orienting to people, socially it may appear more acceptable, but you’re also getting rich information from those people, which will affect the way you’re interacting with people more broadly,” Voos explained. “Say a child wants to draw, and asks for a red crayon while she has her back to me. I say, ‘I can’t understand what you’re asking if you’re not looking at me.’ Once she orients toward me, we provide a contingent response — in this case, giving her the red crayon — and ideally she begins to understand, ‘Hey, me looking at you and asking for what I want gets me what I want.’ Ultimately, the social interaction becomes the reward on its own, which is the ultimate goal.”

The Yale study involved two children, who each received the same amount of therapy — eight to ten hours each week, for four months — bookended by fMRIs looking at predetermined regions of the brain. Small by design, according to Voos, the project was meant to show that PRT does impact processing, and is not simply inspiring learned behavioral changes. It was also intended as impetus for further, more comprehensive study.

“The logical next step is to assess a larger group of children that are the same age as these two, to see whether these improvements were unique to these kids,” Voos said. “We also want to know if the changes we saw remain after treatment. Long-term, it would be amazing to do this with hundreds of kids, in different age groups, to see what differences there may be. I would postulate that the younger we start these kids in treatment, the more improvement we will see in the way that they process social stimuli.”

And therein lies the larger message of this study, according to Voos.

“Early intervention is wonderful,” she said. “It can make serious improvements not only in overt behavior, but potentially in the way children are processing the world around them and the way they’re processing your interaction with them on a daily basis. Even if they’re only minor changes, the fact that they have those shifts, and are potentially processing social stimuli in a more ‘typical’ manner for the rest of their lives, is pretty powerful to think about.”

“Traditional neuro-imagers will say you can’t do MRI with single subjects,” she acknowledged. “This is still giving us a lot of useful information. It might be a different way of using the technology, but we think it’s beneficial. And we don’t think these are random findings. They make sense to us, and it’s exciting.”

Neurostiintele si atasamentul uman

http://brainposts.blogspot.it/2013/01/neuroscience-of-human-attachment.html

 

Attachment is the ability to form human relationship bonds.  Individuals vary in their ability to develop social relationships.  The ability to form secure human relationships plays a key role in successful personal and occupational development.

Attachment theory evolved over 50 years ago.  This theory proposes all humans have an innate biological mechanism that supports social engagement.  This engagement is necessary during infancy to encourage nurturance and provision of a safe environment.

Bowlby is credited with describing attachment theory and he proposed three developmental styles of attachment.  These three attachment styles included:

  • Secure attachment: an ability to easily seek and obtain support from others.  This style promotes strong bonds with parents, siblings, friends and later in life allows for bonding with a mate.
  • Anxious attachment: a insecure attachment style where emotional support has often been inconsistent during childhood.  Individuals with anxious attachment develop hypersensitivity to interpersonal rejection and have anxiety in social environments.  They may develop a needy approach to relationships constantly seeking reassurance of the strength of social supports.
  • Avoidant attachment: an insecure attachment style that may have been characterized by early social adverse environments.  Individuals with insecure attachment style built a wall around their life denying a need or interest in human interactions.

Emerging research in social neuroscience is providing a better understanding of brain mechanisms related to human attachment.  Vrticka and Vuilleumier of the University of Geneva in Switzerland recently published an excellent review of the neuroscience of human attachment in the journal Frontiers in Human Neuroscience.

The authors of this review begin by noting research showing attachment has profound effects in the domains of emotion processing, selective attention and memory.  Insecure attachment individuals are hypersensitive to changes in the expression of emotions in others.   Anxious attachments individuals have enhanced attention to threatening cues.  Avoidant attachment individuals inhibit the memory processing of distressful information.

The authors note social approach behavior appears regulated in specific brain regions including the ventral tegmental area, pituitary, striatum and ventral medial orbitofrontal cortex.  Social aversion appears to be regulated through the amygdala, hypothalamus, insula, anterior cingulate and anterior temporal poles.

Social behavior appears to regulated through both affective evaluation (emotional mentalization) and cognitive control systems (cognitive mentalizations).  These systems interact with hormonal and neurotransmitter domains in influencing social interactions.

The neuroscience of human attachment includes emerging research showing the importance of mental state representation of others (theory of mind).  Mothers with high sensitivity to the cries of their own infants during the post partum period show increased gray matter and fMRI BOLD responses in the prefrontal cortex, superior temporal sulcus and fusiform gyrus.  These regions have been identified as key components engaged in being aware of the emotional states of others.

The authors conclude that the neuroscience of human attachment is beginning to outline key common and distinct elements in avoidant and anxious attachment styles.  Attachment styles appear to be influenced by both environmental history as well as neurobiological factors, some of which may have strong genetic contributions.

Future neuroscience of research will need to move experiments into the “real world” and not be limited to task in brain scanners.  Additionally, future research needs to target early intervention studies in children with attachment problems to find the most effective methods to improve social outcomes.

Readers with more interest in this review are directed to the DOI link below where the free full text manuscript can be found.

Vrtička, P., & Vuilleumier, P. (2012). Neuroscience of human social interactions and adult attachment style Frontiers in Human Neuroscience, 6 DOI: 10.3389/fnhum.2012.00212

 

Invatarea limbajului incepe din viata intrauterina

Sursa: http://www.sciencedaily.com/releases/2013/01/130102083615.htm

Language Learning Begins in Utero, Study Finds; Newborn Memories of Oohs and Ahs Heard in the Womb

Newborns are much more attuned to the sounds of their native language than first thought. In fact, these linguistic whizzes can up pick on distinctive sounds of their mother tongue while in utero, a new study has concluded.


Research led by Christine Moon, a professor of psychology at Pacific Lutheran University, shows that infants, only hours old showed marked interest for the vowels of a language that was not their mother tongue.

“We have known for over 30 years that we begin learning prenatally about voices by listening to the sound of our mother talking,” Moon said. “This is the first study that shows we learn about the particular speech sounds of our mother’s language before we are born.”

Before the study, the general consensus was that infants learned about the small parts of speech, the vowels and the consonants, postnatally. Moon added. “This study moves the measurable result of experience with individual speech sounds from six months of age to before birth,” she said. The findings will be published in Acta Paediatricain late December.

For the study Moon tested newborn infants shortly after birth while still in the hospital in two different locations: Madigan Army Medical Center in Tacoma, Wash., and in the Astrid Lindgren Children’s Hospital in Stockholm. Infants heard either Swedish or English vowels and they could control how many times they heard the vowels by sucking on a pacifier connected to a computer.

Co-authors for the study were. Hugo Lagercrantz, a professor at the Karolinska Institute in Sweden as well as a member of the Nobel Assembly, and Patricia Kuhl, Endowed Chair for the Bezos Family Foundation for Early Childhood Learning and Co-Director of the University of Washington’s Institute for Learning and Brain Sciences.

The study tested newborns on two sets of vowel sounds — 17 native language sounds and 17 foreign language sounds, said Kuhl. The researchers tested the babies’ interest in the vowel sounds based on how long and often they sucked on a pacifier. Half of the infants heard their native language vowels, and the other half heard the foreign vowels. “Each suck will produce a vowel until the infant pauses, and then the new suck will produce the next vowel sound,” said Kuhl.

In both countries, the babies listening to the foreign vowels sucked more, than those listening to their native tongue regardless of how much postnatal experience they had. This indicated to researchers that they were learning the vowel sounds in utero.

“These little ones had been listening to their mother’s voice in the womb, and particularly her vowels for ten weeks. The mother has first dibs on influencing the child’s brain,” said Kuhl. “At birth, they are apparently ready for something novel.”

While other studies have focused on prenatal learning of sentences or phrases, this is the first study to show learning of small parts of speech that are not easily recognized by melody, rhythm or loudness. Forty infants were tested in Tacoma and another 40 in Sweden. They ranged in age from 7 to 75 hours after birth.

Vowel sounds were chosen for the study because they are prominent, and the researchers thought they might be noticeable in the mother’s ongoing speech, even against the noisy background sounds of the womb.

The study shows that the newborn has the capacity to learn and remember elementary sounds of their language from their mother during the last 10 weeks of pregnancy (the sensory and brain mechanisms for hearing are intact at 30 weeks of gestational age).

“This is a stunning finding,” said Kuhl. “We thought infants were ‘born learning’ but now we know they learn even earlier. They are not phonetically naïve at birth.”

Prior to the kinds of studies like this one, , it was assumed that newborns were “blank slates,” added Lagercrantz. He said that although it’s been shown that infants seem to be attuned to sounds of their mother tongue, this same effect now seems to occur before birth. This surprised him.

“Previous studies indicate that the fetus seems to remember musical rhythms,” he said. “They now seem to be able to learn language partially.”

Kuhl added that infants are the best learners on the planet and while understanding a child’s brain capacity is important for science, it’s even more important for the children. “We can’t waste early curiosity.”

“The fact that the infants can learn the vowels in utero means they are putting some pretty sophisticated brain centers to work, even before birth,” she said.

Stiinta din spatele meditatiei

http://www.sciencedaily.com/releases/2012/10/121029161452.htm

ScienceDaily (Oct. 29, 2012) — Achieving mindfulness through meditation has helped people maintain a healthy mind by quelling negative emotions and thoughts, such as desire, anger and anxiety, and encouraging more positive dispositions such as compassion, empathy and forgiveness. Those who have reaped the benefits of mindfulness know that it works. But how exactly does it work?

Researchers at Brigham and Women’s Hospital (BWH) have proposed a new model that shifts how we think about mindfulness. Rather than describing mindfulness as a single dimension of cognition, the researchers demonstrate that mindfulness actually involves a broad framework of complex mechanisms in the brain.

In essence, they have laid out the science behind mindfulness.

This new model of mindfulness is published in the October 25, 2012 issue of Frontiers in Human Neuroscience. The model was recently presented to His Holiness The Dalai Lama in a private meeting, entitled “Mind and Life XXIV: Latest Findings in Contemplative Neuroscience.”

The researchers identified several cognitive functions that are active in the brain during mindfulness practice. These cognitive functions help a person develop self-awareness, self-regulation, and self-transcendence (S-ART) which make up the transformative framework for the mindfulness process.

The S-ART framework explains the underlying neurobiological mechanisms by which mindfulness can facilitate self-awareness; reduce biases and negative thoughts; enhance the ability to regulate one’s behavior; and increase positive, pro-social relationships with oneself and others-all-in-all creating a sustainable healthy mind.

The researchers highlight six neuropsychological processes that are active mechanisms in the brain during mindfulness and which support S-ART. These processes include 1) intention and motivation, 2) attention regulation, 3) emotion regulation, 4) extinction and reconsolidation, 5) pro-social behavior, and 6) non-attachment and de-centering.

In other words, these processes begin with an intention and motivation to want to attain mindfulness, followed by an awareness of one’s bad habits. Once these are set, a person can begin taming him or herself to be less emotionally reactive and to recover faster from upsetting emotions.

“Through continued practice, the person can develop a psychological distance from any negative thoughts and can inhibit natural impulses that constantly fuel bad habits,” said David Vago, PhD, BWH Functional Neuroimaging Laboratory, Department of Psychiatry, and lead study author.

Vago also states that continued practice can also increase empathy and eliminate our attachments to things we like and aversions to things we don’t like.

“The result of practice is a new You with a new multidimensional skill set for reducing biases in one’s internal and external experience and sustaining a healthy mind,” said Vago.

The S-ART framework and neurobiological model proposed by the researchers differs from current popular descriptions of mindfulness as a way of paying attention, in the present moment, non-judgmentally. With the help of functional MRI, Vago and his team are currently testing the model in humans.

This research was supported by the Mind and Life Institute, Impact Foundation, and the National Center for Complementary and Alternative Medicine at the National Institutes of Health (5-R21AT002209-02).

Interventia timpurie in autism si activarea cerebrala

http://www.covorasulfermecat.ro/content/interventia-timpurie-autism-si-activarea-cerebrala

Interventia timpurie in autism normalizeaza activitatea cerebrala la copiii de 18 luni
(Articol tradus partial)

Interventia intensiva si timpurie folosita pentru imbunatatirea abilitatilor cognitive si de limbaj la copiii cu autism normalizeaza si activitatea lor cerebrala si diminueaza simptomele. Cercetatorii spun ca acesta este primul studiu care arata ca interventia timpurie in autism poate normaliza activitatea cerebrala.

“Creierele copiilor mici sunt destul de maleabile si s-a demonstrat anterior ca terapia valorifica potentialul de invatare pe care il are un copil, cu scopul de a diminua efectele negative ale autismului”, spune autoarea studiului Sally Rogers, profesor de psihiatrie si stiinte ale comportamentului si cercetatoare la UC Davis Mind Institute. […]

Studiul a fost publicat online pe 26 octombrie 2012 in Journal of the American Academy of Child & Adolescent Psychiatry; este un studiu clinic controlat, intitulat “Interventia comportamentala timpurie este asociata cu normalizarea activitatii cerebrale a copiilor mici cu autism”. Cercetatorii au aflat ca acei copii cu autism care au beneficiat de interventia propusa de ei au o activare cerebrala mai intensa atunci cand privesc fețele oamenilor, comparativ cu privitul obiectelor. Acesta este un raspuns obisnuit pentru copiii care nu au autism. La copiii cu autism inclusi in studiu care nu au beneficiat de interventia propusa, nu s-a observat acest lucru. […]

Interventia folosita in studiu, numita Early Start Denver Model (ESDM) a fost propusa de Rogers si Geraldine Dawson, autoarea principala a studiului si sustinatoarea activa a Autism Speaks. Terapia are la baza jocul, relationarea, dezvoltarea normala si utilizeaza metode de invatare din analiza comportamentala aplicata. […]

Pentru acest studiu, au fost alesi 48 copii (baieti si fete) diagnosticati cu autism, cu varste intre 18 si 30 luni din Sacramento (California) si din Seattle. Au fost recrutati si copii cu dezvoltare normala, pentru a realiza grupul de control. Proportia baieti-fete a fost 3:1. Autismul este de 5 ori mai intalnit in randul baietilor decat in randul fetelor. […]

Aproximativ jumatate dintre copiii cu autism au primit aleator interventia propusa timp de 2 ani. Participantii au beneficiat aleator de ESDM 20 ore pe saptamana, iar parintii au fost instruiti sa ofere interventia. Ceilalti participanti cu autism au primit alte interventii din comunitate, precum si evaluari, manuale si alte materiale de citit. […]

Unsprezece din cei 15 copii care au primit interventia ESDM (73%) au avut activitate cerebrala mai intensa cand au privit fețe decat atunci cand au privit jucarii. Similar, 12 din cei 17 copii cu dezvoltare normala (71%) au avut acelasi raspuns. Insa, 64% dintre copiii cu autism care nu au primit aceasta interventie au avut raspunsul opus, “autist”: activare cerebrala mai intensa la privitul jucariilor si nu al fețelor. Doar 5% dintre ei au avut activarea cerebrala a copiilor cu dezvoltare normala. […]

“Pentru prima data” spune Dawson, “parintii si practicienii au dovada stiintifica a faptului ca interventia timpurie are impact asupra creierului si a comportamentului la copiii mici. Este esential ca toti copiii cu autism sa aiba acces la o interventie timpurie care sa conduca la efecte benefice pe termen lung”. […]

Puteti citi articolul original aici:
http://www.sciencedaily.com/releases/2012/10/121026125021.htm

Psiholog Claudia Draganescu