Posts tagged "autism"
Autism Redefined: New Diagnostic Criteria More Restrictive
The proposed changes to the diagnostic definition would be published in the fifth edition of the American Psychiatric Association’s (APA) “Diagnostic and Statistical Manual of Mental Disorders (DSM-5).”
 
"Given the potential implications of these findings for service eligibility, our findings offer important information for consideration by the task force finalizing DSM-5 diagnostic criteria," said Yale Child Study Center (CSC) director Fred Volkmar, M.D., who conducted the study with CSC colleagues Brian Reichow and James McPartland.
Volkmar and his team found that in a group of individuals without intellectual disabilities who were evaluated during the 1994 DSM-IV field trial, it was estimated that approximately half might not qualify for a diagnosis of autism under the proposed new definition.
Volkmar stressed that these preliminary findings relate only to the most cognitively able and may have less impact on diagnosis of more cognitively disabled people. “Use of such labels, particularly in the United States, can have important implications for service,” he said. “Major changes in diagnosis also pose issues for comparing results across research studies.”
(http://www.sciencedaily.com/releases/2012/01/120120184525.htm)

Autism Redefined: New Diagnostic Criteria More Restrictive

The proposed changes to the diagnostic definition would be published in the fifth edition of the American Psychiatric Association’s (APA) “Diagnostic and Statistical Manual of Mental Disorders (DSM-5).”

"Given the potential implications of these findings for service eligibility, our findings offer important information for consideration by the task force finalizing DSM-5 diagnostic criteria," said Yale Child Study Center (CSC) director Fred Volkmar, M.D., who conducted the study with CSC colleagues Brian Reichow and James McPartland.

Volkmar and his team found that in a group of individuals without intellectual disabilities who were evaluated during the 1994 DSM-IV field trial, it was estimated that approximately half might not qualify for a diagnosis of autism under the proposed new definition.

Volkmar stressed that these preliminary findings relate only to the most cognitively able and may have less impact on diagnosis of more cognitively disabled people. “Use of such labels, particularly in the United States, can have important implications for service,” he said. “Major changes in diagnosis also pose issues for comparing results across research studies.”

(http://www.sciencedaily.com/releases/2012/01/120120184525.htm)

Humans and Apes: The Autistic Connection?
A young male bonobo residing at the Great Ape Trust refuge is showing signs of autism.  The 1-year-old named Teco is exhibiting behavior similar to autistic human children, including repetitive motions and a lack of eye contact. Read on to learn more about little Teco.
 
Teco isn’t acting like others his age.
Constantly on the move, performing repetitious behaviors and avoiding eye contact, he puzzled his mother, who didn’t know how to handle him at first.
Surely, this isn’t normal behavior for a 1-year-old bonobo, who should be learning the ins and outs of his ape social group.
Speculating the roots of Teco’s change, his caregivers at Great Ape Trust put forth a surprising theory: What if Teco is autistic?
Such a finding may come as a surprise to the primatology community, which is familiar with the stunning intellegence of Teco’s dad, Kanzi. From observing so far, experts think Teco’s autistic-like behaviors add to a growing list of similarities between humans and their recent primate ancestors. If the young bonobo has indeed developed a neurological condition akin to autism, then researchers might learn more about the disorder’s roots and how it affects other species.
But the claim raises a larger question: Are mental health disorders unique to humans, or are we too ill-equipped to understand the complexity of the nonhuman animal psyche?
It’s tough to say, since we can’t extrapolate human behavior onto another species. What’s worth noting, however, is primate-behavior experts’ ability to discern Teco’s actions and label them abnormal for his species.
After looking at video demonstrating Teco’s strong connection with a human caregiver, I was surprised to learn about changes in this youngster. In the first video, Teco didn’t appear to have problems with social issues, such as maintaining eye contact. Yet, between September 2010 and now, something in Teco’s development seems to have veered off course.
Could the primate’s unnatural rearing or early interaction with humans be affecting his developmental trajectory? It’s not clear and likely won’t be for some time.
Autism spectrum disorders, limited to humans so far, affect nearly one in nearly 110 children, according to the Centers for Disease Control and Prevention. Because of the complexity of the condition, it’s difficult to know for sure if Teco’s behaviors were shaped by the same factors as children who live with signs of autism.

Humans and Apes: The Autistic Connection?

A young male bonobo residing at the Great Ape Trust refuge is showing signs of autism.  The 1-year-old named Teco is exhibiting behavior similar to autistic human children, including repetitive motions and a lack of eye contact. Read on to learn more about little Teco.

Teco isn’t acting like others his age.

Constantly on the move, performing repetitious behaviors and avoiding eye contact, he puzzled his mother, who didn’t know how to handle him at first.

Surely, this isn’t normal behavior for a 1-year-old bonobo, who should be learning the ins and outs of his ape social group.

Speculating the roots of Teco’s change, his caregivers at Great Ape Trust put forth a surprising theory: What if Teco is autistic?

Such a finding may come as a surprise to the primatology community, which is familiar with the stunning intellegence of Teco’s dad, Kanzi. From observing so far, experts think Teco’s autistic-like behaviors add to a growing list of similarities between humans and their recent primate ancestors. If the young bonobo has indeed developed a neurological condition akin to autism, then researchers might learn more about the disorder’s roots and how it affects other species.

But the claim raises a larger question: Are mental health disorders unique to humans, or are we too ill-equipped to understand the complexity of the nonhuman animal psyche?

It’s tough to say, since we can’t extrapolate human behavior onto another species. What’s worth noting, however, is primate-behavior experts’ ability to discern Teco’s actions and label them abnormal for his species.

After looking at video demonstrating Teco’s strong connection with a human caregiver, I was surprised to learn about changes in this youngster. In the first video, Teco didn’t appear to have problems with social issues, such as maintaining eye contact. Yet, between September 2010 and now, something in Teco’s development seems to have veered off course.

Could the primate’s unnatural rearing or early interaction with humans be affecting his developmental trajectory? It’s not clear and likely won’t be for some time.

Autism spectrum disorders, limited to humans so far, affect nearly one in nearly 110 children, according to the Centers for Disease Control and Prevention. Because of the complexity of the condition, it’s difficult to know for sure if Teco’s behaviors were shaped by the same factors as children who live with signs of autism.

 
How long we look at happy faces is in our genes
Though we all depend on reading people’s faces, each of us sees others’ faces a bit differently. Some of us may gaze deeply into another’s eyes, while others seem more reserved. At one end of this spectrum people with autism spectrum conditions (ASC) look less at other people’s faces, and have trouble understanding others people’s feelings. New research published in BioMed Central’s open-access journal Molecular Autism has found variations of the cannabinoid receptor (CNR1) gene that alter the amount of time people spend looking at happy faces.
The new research was led by Dr Bhismadev Chakrabarti at the University of Reading and Professor Simon Baron-Cohen at the University of Cambridge. Their earlier research had shown that polymorphisms (naturally occurring mutations) in CNR1 were associated with altered activity within the striatum (a region of the brain involved in emotion and reward behavior) in response to happy faces.
In the new study the researchers analyzed the DNA from 28 adult volunteers and tested (using a “gaze tracker”) how long the volunteers looked at eyes and mouths of faces in video clips showing different emotions. The team found variations within two of the four polymorphisms in CNR1 correlated with a longer gaze at happy faces but not with faces showing disgust. Both of these genomic sites involved for happy faces were within part of the DNA which does not code for protein but instead may be involved in regulating protein production.
Dr Chakrabarti commented, “This is the first study to have shown that how much we gaze at faces is influenced by our genetic make-up. If replicated it has profound implications for our understanding of the drive to socialize, and in turn, the atypical use of gaze in autism”.
(EurekAlert!, image courtesy of Science Daily)
… ‘gaze tracker?’ Sometimes scientists are as shameless as this sentence’s alliteration. 

How long we look at happy faces is in our genes

Though we all depend on reading people’s faces, each of us sees others’ faces a bit differently. Some of us may gaze deeply into another’s eyes, while others seem more reserved. At one end of this spectrum people with autism spectrum conditions (ASC) look less at other people’s faces, and have trouble understanding others people’s feelings. New research published in BioMed Central’s open-access journal Molecular Autism has found variations of the cannabinoid receptor (CNR1) gene that alter the amount of time people spend looking at happy faces.

The new research was led by Dr Bhismadev Chakrabarti at the University of Reading and Professor Simon Baron-Cohen at the University of Cambridge. Their earlier research had shown that polymorphisms (naturally occurring mutations) in CNR1 were associated with altered activity within the striatum (a region of the brain involved in emotion and reward behavior) in response to happy faces.

In the new study the researchers analyzed the DNA from 28 adult volunteers and tested (using a “gaze tracker”) how long the volunteers looked at eyes and mouths of faces in video clips showing different emotions. The team found variations within two of the four polymorphisms in CNR1 correlated with a longer gaze at happy faces but not with faces showing disgust. Both of these genomic sites involved for happy faces were within part of the DNA which does not code for protein but instead may be involved in regulating protein production.

Dr Chakrabarti commented, “This is the first study to have shown that how much we gaze at faces is influenced by our genetic make-up. If replicated it has profound implications for our understanding of the drive to socialize, and in turn, the atypical use of gaze in autism”.

(EurekAlert!, image courtesy of Science Daily)


… ‘gaze tracker?’ Sometimes scientists are as shameless as this sentence’s alliteration. 

Autism Changes Molecular Structure of the Brain: Discovery Points to a Common Cause for Multifaceted Disease
For decades, autism researchers have faced a baffling riddle: how to unravel a disorder that leaves no known physical trace as it develops in the brain.
Now a UCLA study is the first to reveal how the disorder makes its mark at the molecular level, resulting in an autistic brain that differs dramatically in structure from a healthy one. Published May 25 in the advance online edition of Nature, the findings provide new insight into how genes and proteins go awry in autism to alter the mind.
The discovery also identifies a new line of attack for researchers, who currently face a vast array of potential fronts for tackling the neurological disease and identifying its diverse causes.
"If you randomly pick 20 people with autism, the cause of each person’s disease will be unique," said principal investigator Dr. Daniel Geschwind, the Gordon and Virginia MacDonald Distinguished Chair in Human Genetics and a professor of neurology and psychiatry at the David Geffen School of Medicine at UCLA. "Yet when we examined how genes and proteins interact in autistic people’s brains, we saw well-defined shared patterns. This common thread could hold the key to pinpointing the disorder’s origins."
The research team, led by Geschwind, included scientists from the University of Toronto and King’s College London. They compared brain tissue samples obtained after death from 19 autism patients and 17 healthy volunteers. After profiling three brain areas previously linked to autism, the group zeroed in on the cerebral cortex, the most evolved part of the human brain.
The researchers focused on gene expression — how a gene’s DNA sequence is copied into RNA, which directs the synthesis of cellular molecules called proteins. Each protein is assigned a specific task by the gene to perform in the cell.
By measuring gene-expression levels in the cerebral cortex, the team uncovered consistent differences in how genes in autistic and healthy brains encode information.
"We were surprised to see similar gene expression patterns in most of the autistic brains we studied," said first author Irina Voineagu, a UCLA postdoctoral fellow in neurology. "From a molecular perspective, half of these brains shared a common genetic signature. Given autism’s numerous causes, this was an unexpected and exciting finding."
The researchers’ next step was to identify the common patterns. To do this, they looked at the cerebral cortex’s frontal lobe, which plays a role in judgment, creativity, emotions and speech, and at its temporal lobes, which regulate hearing, language and the processing and interpreting of sounds.
When the scientists compared the frontal and temporal lobes in the healthy brains, they saw that more than 500 genes were expressed at different levels in the two regions.
In the autistic brains, these differences were virtually non-existent.
"In a healthy brain, hundreds of genes behave differently from region to region, and the frontal and temporal lobes are easy to tell apart," Geschwind said. "We didn’t see this in the autistic brain. Instead, the frontal lobe closely resembles the temporal lobe. Most of the features that normally distinguish the two regions had disappeared.”
Two other clear-cut patterns emerged when the scientists compared the autistic and healthy brains. First, the autistic brain showed a drop in the levels of genes responsible for neuron function and communication. Second, the autistic brain displayed a jump in the levels of genes involved in immune function and inflammatory response.
"Several of the genes that cropped up in these shared patterns were previously linked to autism," said Geschwind. "By demonstrating that this pathology is passed from the genes to the RNA to the cellular proteins, we provide evidence that the common molecular changes in neuron function and communication are a cause, not an effect, of the disease.”
The next step will be for the research team to expand its search for the genetic and related causes of autism to other regions of the brain.
(SD)

Autism Changes Molecular Structure of the Brain: Discovery Points to a Common Cause for Multifaceted Disease

For decades, autism researchers have faced a baffling riddle: how to unravel a disorder that leaves no known physical trace as it develops in the brain.

Now a UCLA study is the first to reveal how the disorder makes its mark at the molecular level, resulting in an autistic brain that differs dramatically in structure from a healthy one. Published May 25 in the advance online edition of Nature, the findings provide new insight into how genes and proteins go awry in autism to alter the mind.

The discovery also identifies a new line of attack for researchers, who currently face a vast array of potential fronts for tackling the neurological disease and identifying its diverse causes.

"If you randomly pick 20 people with autism, the cause of each person’s disease will be unique," said principal investigator Dr. Daniel Geschwind, the Gordon and Virginia MacDonald Distinguished Chair in Human Genetics and a professor of neurology and psychiatry at the David Geffen School of Medicine at UCLA. "Yet when we examined how genes and proteins interact in autistic people’s brains, we saw well-defined shared patterns. This common thread could hold the key to pinpointing the disorder’s origins."

The research team, led by Geschwind, included scientists from the University of Toronto and King’s College London. They compared brain tissue samples obtained after death from 19 autism patients and 17 healthy volunteers. After profiling three brain areas previously linked to autism, the group zeroed in on the cerebral cortex, the most evolved part of the human brain.

The researchers focused on gene expression — how a gene’s DNA sequence is copied into RNA, which directs the synthesis of cellular molecules called proteins. Each protein is assigned a specific task by the gene to perform in the cell.

By measuring gene-expression levels in the cerebral cortex, the team uncovered consistent differences in how genes in autistic and healthy brains encode information.

"We were surprised to see similar gene expression patterns in most of the autistic brains we studied," said first author Irina Voineagu, a UCLA postdoctoral fellow in neurology. "From a molecular perspective, half of these brains shared a common genetic signature. Given autism’s numerous causes, this was an unexpected and exciting finding."

The researchers’ next step was to identify the common patterns. To do this, they looked at the cerebral cortex’s frontal lobe, which plays a role in judgment, creativity, emotions and speech, and at its temporal lobes, which regulate hearing, language and the processing and interpreting of sounds.

When the scientists compared the frontal and temporal lobes in the healthy brains, they saw that more than 500 genes were expressed at different levels in the two regions.

In the autistic brains, these differences were virtually non-existent.

"In a healthy brain, hundreds of genes behave differently from region to region, and the frontal and temporal lobes are easy to tell apart," Geschwind said. "We didn’t see this in the autistic brain. Instead, the frontal lobe closely resembles the temporal lobe. Most of the features that normally distinguish the two regions had disappeared.”

Two other clear-cut patterns emerged when the scientists compared the autistic and healthy brains. First, the autistic brain showed a drop in the levels of genes responsible for neuron function and communication. Second, the autistic brain displayed a jump in the levels of genes involved in immune function and inflammatory response.

"Several of the genes that cropped up in these shared patterns were previously linked to autism," said Geschwind. "By demonstrating that this pathology is passed from the genes to the RNA to the cellular proteins, we provide evidence that the common molecular changes in neuron function and communication are a cause, not an effect, of the disease.

The next step will be for the research team to expand its search for the genetic and related causes of autism to other regions of the brain.

(SD)