Approximately 25–30% of children with autism spectrum disorders stop speaking after beginning to say words, often before the age of two. According to Ami Klin, "Most examples of autistic regression...are based upon a child's loss of a handful of words...it's possible that these children were only echoing sounds they heard from their parents"(Hughes, V. 2008). Some children lose social development instead of language; some lose both. After the regression, the child follows the standard pattern of autistic neurological development. The term refers to the appearance that neurological development has reversed; it is actually only the affected developmental skills, rather than the neurology as a whole, that regresses. It is more usual for autistic neurological development to not include such aberrations, with age-appropriate autistic symptoms being clear from birth.
Skill loss may be quite rapid, or may be slow and preceded by a lengthy period of no skill progression; the loss may be accompanied by reduced social play or increased irritability. The temporarily acquired skills typically amount to a few words of spoken language, and may include some rudimentary social perception. In some cases a child will go through a period of learning new words at the cost of losing previously acquired words.
Regression in autism spectrum disorders is well documented; attribution of regression to environmental stress factors may result in a delay in diagnosis. The apparent onset of regressive autism is surprising and distressing to parents, who often initially suspect severe hearing loss. The pattern of symptoms naturally leads many to suspect that postnatal environmental factors trigger autism; frequently, the apparent factor cited by parents is the possibility of vaccine injury. In particular, because obvious symptoms often start just after children receive multiple vaccinations, such as the MMR vaccine or the MMRV vaccine (MMR plus varicella (chickenpox) vaccine), some people perceive a causal link between vaccination and autism, especially if accompanied by a fever, rash, and rapid skill loss. Although a rancorous controversy has escalated since the earliest reports of a possible link began to surface in the 1980s, no link has been found with vaccines. There are also studies being done to test if certain types of regressive autism have an autoimmune basis. These studies show that some children are unable to absorb food due to a genetic disorder of their small intestine (see autistic enterocolitis). These children seem to respond to treatment. (Vogin, G. D. 2002)
There are some who believe that regressive autism is simply early-onset autism that was recognized at a later date. Researchers have conducted studies to determine whether regressive autism is a distinct subset of [[autism spectrum
There are some who believe that regressive autism is simply early-onset autism that was recognized at a later date. Researchers have conducted studies to determine whether regressive autism is a distinct subset of [[autism spectrumdisorders. Over the years, the results of these studies have contradicted one another. Some researchers believe there is still nothing to support a definitive biological difference between early-onset and regressive autism. Some view all autism as regressive, a possibility examined in studies involving younger siblings of children with autism.
Peripheral blood leukocyte production of BDNF following mitogen stimulation in early onset and regressive autism.(brain-derived neurotrophic factor)(Clinical report)
Mar 22, 2008; Abstract: Brain-derived neurotrophic factor (BDNF) is critical for neuronal differentiation and synaptic development. BDNF is...