Information on autism
(Autism spectrum disorders)
- Most common features related to Autism Spectrum Disorders
Autism is a
neurological disorder which severely impairs a child's ability to communicate
and appropriately interact socially. Autism disrupts the capacity of the
child to spontaneously and naturally learn from his environment. It
is a developmental disability which affects thought, perception, attention and
often the control of body motions and posture. It is a broad
spectrum of disorders that ranges from mild to severe. It is also
referred to as Pervasive Developmental Disorder (PDD). For
more on neurological causes go to Conferences and
Articles.
Autism Spectrum Disorder encompasses many different
disorders, all of them involving an impairment of social emotional skills .
Different diagnosis are given according to the severity and/or the
specificity of the impairment. They include the
following : ASD for Autism Spectrum Disorder, PDD-NOS for Pervasive
Developmental Disorder Not Otherwise Specified, AS for Asperger Syndrome.
Rett Syndrome, Smith Magenis Syndrome, Fragile X chromosome Syndrome also
pertain to the spectrum of Autism Disorder. Even within
the same diagnosis , people share as many characteristics as they
display noticeable differences in their adaptive and cognitive capacities.
Children
with autism exhibit a wide range of behavioral deficiencies and excesses. (for
more on behavioral deficiencies, click on Related Disorders) Autism is
the third most common developmental disability today, affecting, in some
estimates, as many as 1 in 166 children. It is four times more prevalent in
boys than girls. This disorder seems linked to a Central Nervous System
dysfunction resulting in a sensory/emotion processing and modulation
impairment.
Most common features related to Autism Spectrum Disorder
(for more
detailed information on early signs of autism click here)
(for
information on communication milestones in typical children , see Typical Child section
- No or little eye contact;
- Failure to respond to name;
- Failure to use facial expression or gesture to communicate;
- Impaired capacity to label facial expressions on others.;
- Deficit in sharing interest with others;
- Restricted play repertoire and often no representational play;
- Delays in the acquisition of spoken language or aberrant language such as mechanical flow of speech, poor pragmatic of speech and echolalia (i.e., out of context repetition of the last sound heard);
- Deficit in initiating relation with peers;
- Abnormally intense preoccupation with one subject, activity, or with part of an object;
- Distress over change, insistence on routines or rituals;
- impaired responses to sensory stimuli
- Repetitive body movements;
- Purposeless and incessant motion
- Disrupted sleep patterns
- Difficulty regulating and expressing emotions
Sensory
processing (integration) Sensory regulation
It refers to the capacity of the
nervous system to continually and accurately register, process and respond
accordingly to sensory information (external as well as internal). The
capacity to process and regulate sensory information is , in part, an
evaluation of the capacity to elaborate appropriate responses to various
stimuli.
Poor sensory modulation can occur within
any of the sensory systems: tactile, motor (proprioceptive -i.e., related to
body posture- and vestibular -related to balance), auditory, visual, smell or
taste.
Often, the nervous systems of children
displaying a sensory processing impairment may not modulate sensory
information properly and may alert and arouse to the wrong cues or may fail to
alert at all. Most oppositional behaviors could result from a difficulty
in processing sensory input and the surge of emotions it triggers. A
hypersensitivity to sounds makes sound production and attending to
sounds painful processes thus rendering speaking and
listening an aversive experience. Children with strong tactile defensiveness
react very negatively to being held and cuddled. It seems as if children
with Autism perceive (and/or react to) their environment in either an altered
or distorted manner or in an amplified mode.
Sensory information, after being
processed in the corresponding sensory area, is relayed to the Amygdala which
is the portal of the sensory regulation system. The Amygdala is located
deep within the temporal globe. It is responsible for arousal, control of
autonomic responses associated with fear, emotional responses, formation and
storage of memory associated with emotional events. The Amygdala is also
involved in memory consolidation., thus in learning process. Integrating
information gathered through the individual's previous experiences, the
Amygdala sends cascading information to the autonomous nervous system to
prepare the body response to the sensory stimuli.
Children with autism appear to distort emotional significance of
sensory information, (displaying responses irrelevant with the stimuli, e.g.,
expression of fear triggered by the sight of certain food and absence of fear
in front of an obviously mean dog). This could be the result of faulty
connections ( by neuro-chemicals) in between the cortical areas that process
information and the Amygdala, and/or between the Amydgala and the limbic
system, and the frontal lobes that elaborate and regulate the resulting
behaviors.
Self stimulatory behaviors are resulting from sensory
impairment. They have a calming effect on individuals with autism
performing them. They are in fact, (unsuitable) self regulating
behaviors, in response to a sensory overload and/or emotional
distress. Unfortunately the high incidence of those behaviors prevents
the individuals performing them from attending to their social environment
causing further delay in learning and relating.
Concomitantly self stimulatory behaviors lead to a
measurable reduction of skin conduction. Distortion in sensory regulation
was evaluated in children with autism by measuring the increase of their skin
conductance while exposed to a variety of sensory information. The
increase of skin conductance is caused by an increase in sweating. All
the children had an overall increased autonomic response (heart beat, sweating)
but their responses varied randomly, and disproportionably with the stimuli
they were exposed to. They could be agitated when exposed to trivial
events and display little reaction to arousing events. Their sensory landscape
is obviously disrupted. Monitoring a child ‘skin conductivity could give
valuable information aiming at preparing the child to regulate and integrate
relevant sensory information that appear disruptive to him.
The disorder seems to affect the way emotions
are perceived and expressed and the way in which the body regulates the
emotional flow. Emotions whether primary, (happiness, fear, anger, sadness) or
secondary (also called social emotions) are complicated productions of chemical
and neural expressions forming a pattern in response to sensory information and
memory retrieval.
All emotions have some kind of
regulatory role to play; they should assist in the body's survival. The
first biological function of an emotion is the regulation of the internal state
of the body ( blood flow, temperature, heart beat , gastro intestinal
motility, level of arousal…). The second function is to produce an
appropriate external (social) reaction to an inducing situation. Most
children with PDD display an emotional repertoire that seems to follow a
very confused and confusing internal clock .
75% of them suffer from some gastro
intestinal problem similar to those resulting from a very high stress level.
The disorders range from allergies to various motility disorders. The gastro
intestinal problems could account for many unexplained outbursts and for some
of the poor sleep patterns ( along with the spikes seen on the EEG) many
children under the autism spectrum disorders experience.
Self stimulating behavior such as hand
flapping, rocking, biting the skin, clothes or objects, constant wandering, may
result from poor emotional and sensory regulation. Acting out and temper
tantrums might be the consequences of high arousal levels to complex environments.
Children with autism have also a
severe impairment in their ability to label emotions on others, leading to
their social awkwardness.
Many children within the PDD range are
also affected by dyspraxia, apraxia or both. Developmental
dyspraxia is an impairment or an immaturity of the organization of
movement. It is an immaturity in the way the brain processes information,
which results in messages not being properly or fully transmitted. The term
dyspraxia comes from the Greek word "praxis", which means
doing, acting. Dyspraxia affects thinking process, planning , and
carrying out motor tasks, (conceptualizing what to do and how to do it).
It is associated with problems of perception and language. Children with
dysraxia may suffer from the following:
Poor
balance.
Poor
fine and gross motor co-ordination.
Poor
posture.
Difficulty
with throwing and catching a ball.
Poor
awareness of body position in space.
Poor
sense of direction.
Difficulty
hopping, skipping or riding a bike.
Sensitive
to touch.
Confused
about which hand to use.
Slow
to learn to dress or feed themselves.
Difficulty
with reading, writing.
Speech
problems - slow to learn to speak and speech may be incoherent.
Verbal Apraxia ( labeled as Apraxia of
speech by the American Speech Language Hearing Association, ASHA) is a disorder
of the nervous system affecting the ability to sequence and coordinate mouth
and speech movements resulting in an difficulty imitating sounds, syllables and
words. It is not due to a muscular weakness but it resides in an impairment in
the brain’s planning to move the parts of the body involved with the
production of speech. The child might know what he is trying to say but the
brain is not sending the proper motor instruction.
Hypotonia
and hypertonia
Hypotonia is a disorder involving decreased
skeletal muscles tone, and hypertonia refers to an increased tightness
of muscle tone . They are often diagnosed in children with autism.
Both may suggest a central nervous system dysfunction.
For information on other related impairments, click here.
There is no known single cause for autism, it seems to be largely
a genetic and polygenic (involving several genes) disease. It is
generally accepted that the inherited genetic variations cause
abnormalities in brain structures and function. Brain scans show
differences in the shape and structure of the brain of Children with
Autism versus non-autistic children's brain.. 30 to 70 % of
children with autism have abnormal EEG ((Electroencephalogram) images
displaying EEG spikes, and about one-third of children and adolescents with
autism develop seizures.
The spikes
although different from seizures in intensity and frequency , stem
from a similar abnormal electro encephalic activity.
There
are clear evidence that children with Autism and PDD are born with the disorder
or with the potential to develop it. Poor parenting cannot cause it: no
psychological factors have proven to cause autism. Autism is a
developmental disorder. Children with autism are not unruly kids who choose not
to behave.
The primary cause seems to be genetic.
Siblings of people with autism have a 3 to 10 percent chance
of being diagnosed with the same disorder. The risk is higher if the first
child being diagnosed is a girl. This is much greater than the 0.16 percent
risk in the general population but much less than the 50% chance that would
characterize a genetic disease caused by a single dominant mutation (in which
one faulty gene, inherited from one parent is enough to cause the disorder), or
the 25 percent chance that would characterize a single recessive gene (in
which a copy of the faulty gene inherited by both parents is necessary to cause
the disease).
In many families, there appears to be a pattern of related
disabilities, supporting a genetic basis to the disorder. Evidence
suggests that unaffected family members may share, with their ill relatives,
genes that predispose for milder behavioral characteristics that are qualitatively
similar to those of autism (Learning disability such as reading problem,
certain sensory based avoidant behaviors, attention deficit disorder(ADD) , impaired
social skills, bipolar disorder are often found among the members of the
extended family. More than one gene, and more than one chromosome, are
involved in that disorder. The huge discrepancy between the number of boys and
girls affected could be caused by faulty recessive genes located in the
chromosome X, which could not be counterbalanced in boys, having only one
chromosome X. It could also explain why girls with the disorder tend to have
more severe symptoms and greater cognitive impairment.
Researchers are searching for irregular segments of genetic
code that autistic children may have inherited.
Why such an increase of children diagnosed with Autism. Is
Autism now increasingly more prevalent?
The rate of people being diagnosed with autism has increased
substantially over the past two decades.
What has changed :
!- our access to :
Better tool for
evaluation
Better access to
information for the parents and teachers
Better trained health
servants
2- The Diagnostic and Statistical Manual of
Mental Disorders (DSM) has modified its diagnostic criteria:
Asperger Syndrome
was not codified before the 1990’s and Children suffering from
the disorder were
simply labeled as nerdy and anti social bright kids. There is now a
prevalence of 3 to4 for 1000 .
Not so long ago many
young children with Autism were diagnosed with Childhood
schizophrenia and were considered psychotic. Nowadays the 2 diagnostic
are separate with the onset of Childhood schizophrenia clearly define as being
in the early teens to the soonest. The notion of developmental
disorder is relatively new.
3- Influence of new environmental factors such as pollution
probably play a significant role as well. These additional
triggers might be found in the environment in the form of chemical
pollution ( water, air, use of plastic material and probably many more) and
infections. An immunity deficiency with genetic and/or environmental
causes could also play a part in the development of an Autism disorder.
.
The question of a relationship between vaccines and autism
continues to be debated. Large studies in the US have found no link between
autism and MMR vaccine. (click on
Conferences and Articles.. for more on vaccine,)
Véronique Buré (more information attached here)
Telephone (301) 588 5113
Cell:(202) 375-4443
Electronic mail: sunriseguidance@gmail.com
