Background: Research examining attitudes toward autistic adults has relied on explicit self-report measures, which may be susceptible to socially desirable responding. Because implicit attitudes predict behavioral rejection, understanding both implicit and explicit attitudes toward autistic adults is important. Furthermore, previous research has almost exclusively examined attitudes toward autistic children and has not investigated attitudes toward autistic adults who may also experience prejudice from their peers.

Methods: We created an implicit association test (IAT) to examine implicit attitudes toward autistic adults. In Study 1, we examined 94 neurotypical adults' (mean [M]_age = 31.37 years) implicit attitudes and explicit attitudes toward autistic adults as well as autistic behaviors. In Study 2 (n = 137; M _age = 33.43 years), we assessed the same variables using an IAT with descriptive rather than stereotypical words.

Results: Participants from both studies demonstrated negative implicit attitudes but positive explicit attitudes toward autistic adults. In Study 2, analyses examining self-reported traits related to autism revealed that more autistic behaviors were associated with less implicit bias.

Conclusions: These findings may help explain why autistic adults report discrimination from their peers. The results suggest that there may be benefits in modifying interventions that reduce implicit bias toward other marginalized groups for use with implicit bias against autistic adults.

Lay summary: Why was this study done?: The goal of this study was to understand how neurotypical adults in the United States feel and think about autistic adults. Negative attitudes can lead to discrimination against autistic adults or to harmful interactions between autistic and neurotypical adults. Although research has previously examined the attitudes that neurotypical adults have toward autistic adults, most of this work has directly asked people about their attitudes, assessing their explicit, or conscious, attitudes. Neurotypical adults, however, may not be able or willing to admit that they have negative attitudes toward autistic adults. Therefore, it is important to evaluate implicit attitudes, which are underlying attitudes at the unconscious level of awareness.What was the purpose of this study?: This study investigated the implicit and explicit attitudes that neurotypical adults in the general U.S. population have about autistic adults. Assessing both kinds of attitudes is important because each type of attitude predicts different sorts of behaviors toward and judgments of individuals.What did the researchers do?: We conducted this study online using a crowdsourcing method of data collection (Amazon's Mechanical Turk) that gave us access to adults throughout the United States. We developed and administered a reaction-time task to examine implicit attitudes toward autistic adults. In this task, participants rapidly categorized words associated with autism and words not associated with autism as being "good" or "bad." We assessed explicit attitudes with questions about people's knowledge of autism and their liking for autistic adults. Study 1 measured 94 neurotypical adults' (average age = 31.37 years) implicit and explicit attitudes toward autistic adults; Study 2 measured 137 neurotypical adults' (average age = 33.43 years) implicit and explicit attitudes. Whereas Study 1's implicit task used words associated with stereotypes about autistic adults (e.g., extraverted, independent), Study 2 used nonstereotypical words associated with autism (e.g., autistic, spectrum).What were the results of the studies?: Participants in both studies reported positive explicit attitudes but negative implicit attitudes toward autistic adults. In one study, we also found that neurotypical adults with more autistic traits themselves had more positive implicit attitudes toward autistic adults.What do these findings add to what was already known?: Although previous research examined neurotypical adults' explicit attitudes toward autistic adults, the current study demonstrated that neurotypical adults hold negative implicit attitudes toward autistic adults. These findings may help explain why autistic adults experience discrimination from neurotypical adults. Furthermore, our findings suggest that having more autistic traits can lead to a better understanding of the behaviors associated with autism.What are the potential weaknesses in the study?: Limitations of the study were that we collected the data online rather than in person and we only included neurotypical adults as participants.How will these findings help autistic adults now or in the future?: These results shed light on underlying reasons for the potential negative judgments and discrimination that autistic adults face from neurotypical adults. These findings should encourage policy makers to design and implement training programs to reduce neurotypical adults' negative attitudes toward autistic adults.