The speakers conclusion or point may never be made, and attempts by the listener to elaborate on the speechs content or logic, or to shift to related topics, are often unsuccessful.Children with AS may have a sophisticated vocabulary at a young age and such children have often been colloquially called "little professors" but have difficulty understanding figurative language and tend to use language literally. Children with AS appear to have particular weaknesses in areas of nonliteral language that include humor, irony, teasing, and sarcasm. Although individuals with AS usually understand the cognitive basis of humor, they seem to lack understanding of the intent of humor to share the enjoyment with others. Despite strong evidence of impaired humor appreciation, anecdotal reports of humor in individuals with AS seem to challenge some psychological theories of AS and autism. Motor and sensory perception
Individuals with Asperger syndrome may have signs or symptoms that are independent of the diagnosis but can affect the individual or the family. These include differences in perception and problems with motor skills, sleep, and emotions. Individuals with AS often have excellent auditory and visual perception. Children with ASD often demonstrate enhanced perception of small changes in patterns such as arrangements of objects or well-known images; typically this is domain-specific and involves processing of fine-grained features. Conversely, compared with individuals with high-functioning autism, individuals with AS have deficits in some tasks involving visual-spatial perception, auditory perception, or visual memory. Many accounts of individuals with AS and ASD report other unusual sensory and perceptual skills and experiences.
Although no specific genetic factor has yet been identified, multiple factors are believed to play a role in the expression of autism, given the variability in symptoms seen in children. Evidence for a genetic link is that AS tends to run in families where more family members have limited behavioral symptoms similar to AS (for example, some problems with social interaction, or with language and reading skills). Most behavioral genetic research suggests that all autism spectrum disorders have shared genetic mechanisms, but AS may have a stronger genetic component than autism. There may be shared genes in which particular alleles make an individual vulnerable, and varying combinations result in differing severity and symptoms in each person with AS.A few ASD cases have been linked to exposure to teratogens (agents that cause birth defects) during the first eight weeks from conception. Although this does not exclude the possibility that ASD can be initiated or affected later, it is strong evidence that ASD arises very early in development. Many environmental factors have been hypothesized to act after birth, but none has been confirmed by scientific investigation.