Only a qualified medical or psychological professional can provide a formal diagnosis of Autism Spectrum Disorder (ASD). This article clarifies the characteristics historically known as High-Functioning Autism (HFA) or Asperger’s Syndrome.
Understanding Current Terminology
The terms “High-Functioning Autism” (HFA) and “Asperger’s Syndrome” are no longer used as distinct clinical diagnoses in the current American psychiatric manual. The Diagnostic and Statistical Manual of Mental Disorders, 5th Edition (DSM-5), unified these previous categories into a single diagnosis: Autism Spectrum Disorder (ASD).
The DSM-5 framework introduced severity specifiers to indicate the level of support an individual requires, ranging from Level 1 to Level 3. The characteristics previously associated with HFA or Asperger’s Syndrome now generally correspond to an ASD diagnosis of Level 1, which is defined as “Requiring Support.” Individuals at this level experience noticeable deficits in social communication and may struggle with restricted and repetitive behaviors, but they often require the least amount of support compared to Levels 2 and 3.
A Level 1 designation indicates that, without support, the individual’s challenges would still cause significant impairment in social, occupational, or other important areas of functioning. While they typically have average or above-average intellectual capabilities and may have developed language skills at an expected rate, their social and behavioral differences are still clinically significant.
Observable Signs in Social and Communication Contexts
Children whose traits align with Level 1 ASD often desire social interaction but struggle with the nuanced mechanics of engaging with peers. They may find it difficult to initiate conversations or use unsuccessful approaches when trying to join a group or make friends. This difficulty is often rooted in challenges with social-emotional reciprocity, which involves the back-and-forth flow of interaction.
Communication differences often manifest in the practical use of language, known as pragmatic language. A child may talk at length about a favorite topic, such as trains or dinosaurs, without gauging the listener’s interest. They might also struggle with non-verbal communication, having difficulty interpreting body language, facial expressions, or changes in tone of voice that signal a shift in mood or meaning.
A literal interpretation of language is another common characteristic of Level 1 ASD. The child may not understand jokes, sarcasm, or metaphors, often taking figurative phrases at their exact face value. This can lead to frequent social misunderstandings, even if the child has a rich vocabulary and advanced verbal abilities. They may also have trouble adjusting their communication style to different social contexts.
Distinctive Patterns of Behavior and Thinking
The second core domain of an ASD diagnosis involves restricted, repetitive patterns of behavior, interests, or activities. For children with Level 1 ASD, this often presents as highly specific and intense interests that are abnormal in their focus or intensity. These “special interests” can consume a significant amount of the child’s time and attention.
Adherence to specific routines and a need for sameness can be pronounced, with the child experiencing significant distress or anxiety when faced with unexpected changes. This inflexibility can include rigid thinking patterns, difficulties with transitions between activities, or an insistence on following a precise, unvarying schedule. These behaviors are often a method of self-regulation to manage anxiety.
Sensory sensitivities are also common, involving hyper- or hypo-reactivity to sensory input. A child may cover their ears in response to sounds that others find normal or show a strong aversion to certain textures in clothing or food. These sensory differences are recognized as a formal diagnostic element in the DSM-5 and can significantly impact the child’s comfort and function.
Next Steps in Seeking Professional Evaluation
If a pattern of these social, communicative, and behavioral differences is observed, the first step is to consult with the child’s primary care provider, such as a pediatrician. Parents should prepare by documenting specific examples of observed behaviors, noting when they occur and what seems to trigger them. Detailed information about the child’s developmental history, including milestones, is also important for the evaluation.
The pediatrician can provide an initial screening and then refer the family to specialists who conduct formal ASD evaluations. This diagnostic team may include:
- A developmental pediatrician
- A child psychologist or psychiatrist
- A speech-language pathologist
- An occupational therapist
The formal evaluation often involves standardized, research-backed tools like the Autism Diagnostic Observation Schedule, Second Edition (ADOS-2). This is a play-based assessment where the clinician observes the child’s social and communication behaviors in structured and unstructured situations. The process also includes thorough interviews with parents, such as the Autism Diagnostic Interview, Revised (ADI-R), to gather developmental history and current concerns. A diagnosis opens the door to early intervention and supportive services tailored to the child’s specific needs.