In recent years, there have been significant improvements in assessment and diagnostic procedures for autism spectrum disorders (ASD). Standardized diagnostic instruments have been developed, promoting consistent diagnostic practices among clinicians. For clinical researchers, these instruments have facilitated collaborations across different sites by providing standardized metrics with which to evaluate ASD symptoms. Nevertheless, because ASD remains a diagnosis that is defined on the basis of behavior, there are significant challenges associated with modeling ASD social behaviors in laboratory animals. In order to more effectively study the causes of ASD symptoms and behaviors, there is a need to develop new ways of measuring social behaviors that can be applied to non-human species. Critically, while verbal dialogue between the clinician and patient is integral to clinical diagnoses, it cannot be employed for studies of animal models. However, observations of autistic-like social interactions can be modeled in animals. In this regard, communication between professionals in the clinical and basic sciences is necessary to break down the complex diagnosis into units of social impairment that can be more feasibly measured in different species. This paper presents a discussion between an animal researcher and a clinical psychologist. Using shared affect as an example, we explore potential avenues for increasing the utility of animal models to move us toward a better understanding of the mechanisms underlying social impairments in ASD.
In the absence of molecular biomarkers that can be used to diagnose ASD, current diagnostic tools depend upon clinical assessments of behavior. Research efforts with human subjects have successfully utilized standardized diagnostic instruments, which include clinician interviews with parents and direct observation of the children themselves (Risi et al., 2006). However, because clinical instruments are semi-structured and rely heavily on dynamic social processes and clinical skill, scores from these measures do not necessarily lend themselves directly to experimental investigations into the causes of ASD. Studies of the neurobiology of autism require experimental animal models. Mice are particularly useful, in this regard, for elucidating genetic and toxicologjcal contributions to impairments in social function (Halladay et al., 2009). Behavioral tests have been developed that are relevant to autism (Crawley, 2004, 2007), including measures of repetitive behaviors (Lewis, Tanimura, Lee, & Bodfish, 2007; Moy et al., 2008), social behavior (Brodkin, 2007; Lijam et al., 1997; Moretti, Bouwknecht, Teague, Paylor, & Zoghbi, 2005), and vocal communication (Panksepp et al., 2007). Advances also include development of high-throughput measures of mouse sociability that can be used to reliably compare inbred mouse strains (Moy, et al., 2008; Nadler et al., 2004), as well as measures of social reward (Panksepp & Lahvis, 2007) and empathy (Chen, Panksepp, & Lahvis, 2009; Langford et al., 2006). With continued generation of mouse gene-targeted mice that are directly relevant to genetic linkages in ASD, there remains an urgent need to utilize a full suite of mouse behavioral tests that allows for a comprehensive assessment of the spectrum of social difficulties relevant to ASD. Using impairments in shared affect as an example, this paper explores potential avenues for collaboration between clinical and basic scientists, within an amply considered translational framework.