by Katherine Johnson. M.S., BCBA
Senior Director of Partnerships, LEARN Behavioral
The first child I ever worked with wanted nothing more than to play with Thomas the Tank Engine—all day. Over the years, teaching many different children on the spectrum, I experienced a dazzling array of special interests: animals, birthdates, the Titanic, horror movies, fireworks, constellations, dinosaurs, parades, American Idol, the “guts” of any electronic device. The variation was delightful.
One of the diagnostic criteria for autism is “restricted, repetitive patterns of behavior, interests, or activities,” according to the Diagnostic and Statistical Manual of Mental Disorder, the DSM-5. There’s no doubt that these preferred topics can be absorbing. When an autistic person is engaged in one of their favorite activities, it can be difficult to get them to want to talk about anything else. But while the powerful interests of people on the spectrum have often been called “restricted,” some research shows that people on the spectrum actually report having interest in more topics than people without an autism diagnosis.
Historically, our society has used negative language like “inflexible” and “obsessive” to describe the interests of people on the spectrum, and therapists have often focused on decreasing them, or using them exclusively to reinforce behavior. Autistic advocates and more recent research have started to change the minds of those who would reduce behavior simply because it is “repetitive” or “intense.” In fact, it is becoming all the clearer that special interests can be an important and fulfilling part of autistic living and learning.
What do verbal autistic people tell us about their special interests?
By and large, autistic people speak of their special interests as something that brings joy to their lives. Special interests can be calming, helping people cope with strong emotions and reducing stress. Thøger Kari Hass writes that his special interests differ from hobbies in that he can put hobbies on hold when life becomes overwhelming, while the opposite is true for his special interests. “When I’m going through stress or life changes,” he writes, “I literally need my special interests to stay functional.” While some complain that their fascination with certain topics can begin to eat up spare time, most autistic people feel “enriched, not controlled” by their interests.
Are there other benefits to these interests?
The fact that special interests bring joy and calm is certainly a persuasive reason to rethink old notions of how to approach them, but there are other reasons, too. In 2012, an article published in the Journal of Positive Behavior Interventions showed a significant increase in meaningful social interaction for three teenagers on the spectrum when social groups were created around their specific interests. Since then, many others have followed suit, reporting that focusing on their special interests can help an autistic child shine, leading them to show more affect, use more complex language, and initiate conversation and organize their thoughts better, studies show. This makes sense, considering that a group of researchers at MIT are finding that listening to stories about their special interests actually activates key language regions in the autistic brain.
Other studies have used special interests to improve cooperative play and to ease difficult transitions by integrating them into teaching, rather than by using them as reinforcers. One strategy is the use of “Power Cards,” which are cards that promote social skills by incorporating the autistic child’s special interests into the instruction. 
Even more compelling is research that reveals that “special interests are tied to improved subjective well-being in adults with autism” and that adults engaging in their highly-specific activities had “increased satisfaction with social contacts and leisure time.”  And of course, an interest enjoyed as a child can become an expertise in adulthood—and can occasionally launch a career, such as with Temple Grandin, Clay Marzo, or Jennifer Cook O’Toole.
When to intervene?
Limiting special interests simply because they involve a different focus or greater intensity than those of their peers is no longer the prevailing practice. Even when an interest produces challenges, such as interrupting or monologuing, interventions can target those problem behaviors connected to the special interest without discouraging the interest itself. 
When interests are interfering with a person’s ability to access school, work, or desired social groups, intervention may be appropriate. But again, accessing other environments or expanding interests can be targeted, while simultaneously maintaining time and space for the person’s special interests.
For me personally, one of the most rewarding experiences of my decades of work with children on the spectrum is the privilege of seeing the adults they become. When they were small, our goals were focused on achieving certain levels of language or daily functioning. But when I encounter a former client now, my measure of success is largely wrapped up in their sense of happiness and fulfillment—two things that are often connected to the “restricted” interests they showed as children. One of my former clients owns her own Etsy shop, crocheting and beading items for her dozens of buyers, and echoing her childhood love of beads and crafting. Another works for the transit system, building train schedules—and living exactly the “dream job” his parents joked about when he was three and could lovingly recite every stop of every numbered bus in his town. A third loves to post critiques of restaurants online, taking me back to his second-grade lectures on Italian cheeses.
Redirecting or attempting to de-intensify an autistic person’s favorite topics used to be assumed to help them connect better with neurotypical peers. Now that evidence to the contrary is emerging, it is difficult to argue that this practice is in their best interest. It seems fitting that the extraordinary enthusiasm autistic people have for specific subjects can be leveraged to further enrich their lives. As I’ve witnessed firsthand many times, these passions can help them learn, de-stress, connect with others, and perhaps most importantly, experience pure joy.
For more tips for parents and caregivers, read “How Books Can Help Kids with Autism Build Language.”
 Jordan CJ, Caldwell-Harris CL. Understanding differences in neurotypical and autism spectrum special interests through Internet forums. Intellect Dev Disabil. 2012 Oct;50(5):391-402. doi: 10.1352/1934-9556-50.5.391. PMID: 23025641.
 Koegel R, Fredeen R, Kim S, Danial J, Rubinstein D, Koegel L. Using Perseverative Interests to Improve Interactions Between Adolescents with Autism and their Typical Peers in School Settings. J Posit Behav Interv. 2012 Jul 1;14(3):133-141. doi: 10.1177/1098300712437043. PMID: 24163577; PMCID: PMC3806136.
 Campbell, A., & Tincani, M. (2011). The power card strategy: Strength-based intervention to increase direction following of children with autism spectrum disorder. Journal of Positive Behavior Interventions, 13(4), 240–249. https://doi.org/10.1177/1098300711400608
 Gagnon, E. (2001). Power cards: Using special interests to motivate children and youth with Asperger syndrome and autism. Shawnee Mission, KS: Autism Asperger Publishing
 Fisher, WW, Rodriguez, NM, Owen, TM (2013) Functional assessment and treatment of perseverative speech about restricted topics in an adolescent with Asperger syndrome. Journal of Applied Behavior Analysis 46: 307–311.
 Smerbeck A. The Survey of Favorite Interests and Activities: Assessing and understanding restricted interests in children with autism spectrum disorder. Autism. 2019;23(1):247-259. doi:10.1177/1362361317742140