Autism in a 15-Month-Old Child

Autism is a developmental disorder marked by severe deficits in reciprocal social interaction, communication, and imagination as well as repetitive and restricted patterns of interests and behaviors (1; DSM-IV-TR). Its early-onset symptom profile includes neurological findings (2) and structural and functional brain abnormalities (3); these findings and the chronicity of autism strongly argue for a biological basis, including genetic liabilities (4). Epidemiologic studies indicate rates of 16 children per 10,000 for more narrowly defined autism and up to 40 children per 10,000 for the more broadly defined group of conditions marked by substantial socialization deficits (5). Despite the presumed congenital nature of autism, its identification typically lags behind the onset of symptoms by several years (6–9). Epidemiologic studies currently place the mean age of diagnosis of autism at around 40 months (5). Early identification is very important (10–12) given the current consensus that the beneficial impact of intervention programs increases with earlier treatment (13–15). This is likely a function of early neuroplasticity and the importance of early experiences in shaping behavioral and brain development (16, 17). Over the past decade new information on autism as it appears in the second and third year of life has focused on social orientation and responsivity, communicative development (including both nonverbal communication and spoken language), imitation, and play and symbolic development (18–26) (see reference 27 for a review). However, specific knowledge of the crucial infancy period of development in individuals with autism is currently limited and includes a small number of retrospective studies based...