6 Aspects of ASD:

Social Reasoning-
Social interactions & reasoning are often seen by the child having little to no interests of interacting or with other humans, in fact often the child will seem as if the child's interactions with objects give them more of a benefit.  This is due to a lack of social understanding.

Language Abilities-
Children who have ASD may have little to know vocabulary or be able to express themselves by actual words, instead they may use sounds, to try and communicate. 

Cognition-The cognitive spectrum often starts with a child who has demonstrated severe learning difficulties and is intellectually impaired when assessed on an IQ, or standardized intelligence test. Although autism is considered to be a neurodevelopmental disorder, it does not mean that all aspects of the brain functins are adversely affected.  In fact, quite remarkably an estimate of approximately 10% of children develop savant ?

Special Interests- There is a wide range of interests that will appeal to the child with A SD early on; however the child may have an intense interests , where that object, or interests will occupy a great amount of their time.

Sensory Sensitivity-The spectrum in the dimension of ASD that we know least about lies here within the sensory system. Sadly the most severe expression of sensory overload or extreme sensitivity makes it seem like that child is living in a "war zone". 

Expression and Management of Emotions- The DSM-5 diagnostic criteria refers to a deficit in social-emotional development, and so an assessment of a child with ASD should include an evaluation of their ability to express reciprocal emotions as well as being able to label and identify emotions in them self and in others.  

Genetics-
Original Studies on Twins suggest that a genetic cause of both identical and fraternal twins. As identical twins have a much higher rate of having autism if one twin has it, then the rate 70-90% of the other identical twin having it; however if the twins are fraternal then the rate drops to 0-5% in the second twin. (Hallmayer etal., 2002) 

Neurology-
Neurological studies of autism have focused on neurochemistry, neuropathology and functional neuroimaging. Neuropathological Studies of young children with Autism have shown that 0% and 25% of the children with ASD Level 1- have a heavier and larger brain and head circumference than typical children, known as macrocephaly. With the use of MRI's studies have also shown that along with the larger brains, that there is also an increase in larger brain volumes whereas the cerebellum and cerebral cortex, and also grey matter.  Which means that having a larger and faster growing brain in earlier years may not be beneficial to the development of specific abilities like cognitive, and social, communication skills. 

Possible Errors of Metabolism-Children with PKN (phenylketonuria ) have a deficiency in an enzyme that converts the amino acid phenylalanine to tyrosine; so in other words this deficiency leads to a toxic accumulation resulting in brain function. * A current debate between parents and scientist is whether ASD may be caused in the lack of being able to metabolize gluten.

Infections in Pregnancy and Early Childhood-
Viral infections have been suggested as a cause of autism. In the 1970's it was suggested that Autism may be caused by Rubella, but a recent study has not supported that theory.
* Also immunizations have been a discussed widely in the media to have been linked with causing Autism; however at this point, no one has been able to completely prove this theory.

Autoimmune Disorders-
Recent research indicates that there is an association between autoimmune disorders and Autism. Type 1 diabetes, Crohn's Disease and Celiac Disease are just a few of the autoimmune disorders that have been linked with of Mother's who have at least one child with ASD.

Gender Differences-
Boys have 4 times more likely being diagnosed with ASD then in females; however, the ration can be a 2 to:1 when making a comparison of boys and girls with a Level 1- ASD.