Autism's Clinical Course
Autism is usually detected in the third or fourth year of life. Early hallmarks include a failure to begin pointing, an apparent lack of interest in peers, a disinterest in playing with toys (or a disinterest in playing with them the same way that others of the same age do), and a delay in the development of speech for communicative purposes. Children with autism have a difficult time coordinating verbal and nonverbal forms of communication and therefore often do not mark acknowledgement of being spoken to with a gaze, do not mark their own communicative speech with eye contact directed at the listener, and do not coordinate body gesture with gaze and vocalization in such communicative efforts. Some children with autism develop single words slowly, but then lose these words, seldom use them, or seemingly plateau in language development. Others develop language for the first time around the third or fourth year of life or after initiation of speech therapy. Early language for a child with autism is marked by an instrumental quality with utterances mainly focused on getting needs and wants addressed. There is typically little conversational use of language.
Autism has sometimes been characterized as a primary disorder of failing to develop a theory of mind. Autistic children, especially in the early years, show a fairly universal disability at assuming the perspective of others, engaging in planned deception, or showing empathy or sympathy. The range of emotional recognition and expression is more limited than normal and social-emotional responses are usually severely lacking. When language does develop, it may be characterized by use of immediate or delayed echolalia in the form of repeating what has just been heard (in the case of the former) or repeating something from past experience in its entirety (in the case of the latter). Echolalia often, though not always, serves some abbreviated communicative function resulting in a characteristically stilted manner of discourse.
In addition to social and language deficits, autism is often marked by odd ways of relating to the environment, which may include adherence to unreasonable routines, ritualized ways of carrying out everyday activities, and a general resistance to change. Autistic children may exhibit overly repetitive tendencies in speech and play, and for many, novelty is generally eschewed and exploratory activity is greatly reduced compared to peers. There may be fixations or avoidance of specific sensory stimuli, such as covering the ears to certain kinds of sounds, visually fixating on objects with a strong vertical or horizontal axis, peripheral gazing at objects, sniffing objects not usually smelled, and physical hypersensitivities—a strong aversion to solid foods or certain types of food, or the avoidance of certain types of clothing.