Mild or More Severe? The Symptoms of Adults with PDD

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What exactly is PDD?

Pervasive Development Disorder is a category containing five conditions that includes autism and Aspergers Syndrome. Another specific diagnosis within this category, Pervasive Developmental Disorder - Not Otherwise Specified, is sometimes referred to as a subthreshold condition that shares some, but not all, of the symptoms of autism. Pervasive Development Disorder (PDD) is similar to autism in that each person with the condition is different and behaves differently than another individual with PDD. What sets PDD apart from classic autism includes criteria the condition does not meet to fully warrant an autism diagnosis set by experts. Individuals with PDD may have started exhibiting symptoms a little later, around 3 or 4 years old, than children with classic autism. They also may share many of the same symptoms of autism, but to a lesser degree than others on the spectrum.

Although PDD has generally been considered a milder form of autism, this may just be a false belief. People with PDD may experience some mild symptoms, but other symptoms may be more extreme. Whatever the symptoms of adults with PDD may have, they present themselves enough to interfere with typical functioning on a daily basis.

Symptoms of Adults with PDD

So, what are the symptoms of adults with PDD? Typical symptoms that adults with this disorder may exhibit include:

  • Difficulties using and understanding verbal communication;
  • Difficulties using and understanding nonverbal communication, such as making eye contact, using gestures and facial expressions;
  • Difficulties interacting socially, including relating to people and surroundings;
  • Difficulties moving from one task to another, adjusting to changes in routine or surroundings; Repetitive body movements or patterns of behavior, such as rocking, hand flapping, and spinning;
  • Aggressiveness;
  • Ritualistic or compulsive behaviors;
  • Unusual responses to sensory experiences;
  • Abnormal preoccupations or unusual focus on certain interests;
  • Intellectual and cognitive deficits;
  • Fearlessness and anxiety, and;
  • Difficulties sleeping.

As mentioned above, each individual with PDD is unique and differs in intelligence, abilities, and impairments. Many circumstances in adult life will depend on an individual’s symptoms and the types of, and reactions to, the interventions he or she has had. Individuals with mild symptoms will probably be able to care for themselves in adulthood. Those with typical intelligence will be able to obtain college degrees and find suitable employment. Marriage and parenting may be possible for some, but prove overwhelming for others.

Adults with more severe PDD, as with other autism spectrum disorders and disabilities, will more likely be unemployed or underemployed than typical adults. Individuals who have cognitive impairment will need additional support from family members and professionals to accomplish daily living activities. Those with more severe forms of this condition will likely experience social isolation, too, as romantic relationships and friendships will be very daunting to develop and maintain.


Hirsch, D. (2009). Pervasive Development Disorders (PDDs). Retrieved November 11, 2010, from

PDD-NOS. (n.d.) Autism Speaks. Retrieved November 11, 2010, from