There is ample evidence of impaired sensory-motor acquisition in autism. Combined with anecdotal olfactory-behavioral reports, this suggests that individuals with autism may exhibit a specific olfactory profile. In the current study, Noam Sobel and his colleagues assessed olfactory performance in children undergoing diagnosis for autism. Their measure of performance was nasal airflow during sniffing of odorants. Given that sniffs are odorant-specific, such an assay provides a nonverbal measure of performance.

Genetic factors have been known to play a role in the development of autism, but the contribution of common genetic variations — those that crop up in at least 1 percent of the general population — to the disorder is not known. Randy Buckner and his colleagues at Harvard University developed a new, highly efficient approach to explore the effects of these variations on brain functions associated with autism.

Autism is a developmental disorder that is most likely triggered during prenatal or early postnatal life. Yehezkel Ben‐Ari and his colleagues at the Mediterranean Institute of Neurobiology and the pharmaceutical company Neurochlore, in France, aim to identify the earliest signals of autism that can be detected in the operation of developing brain networks.

Considerable evidence suggests that changes to brain activity in the cerebellum are involved in autism spectrum disorder. In addition, disruption of a molecular pathway that controls protein synthesis — the mTORC1 pathway — has been implicated in the disorder. In a mouse model in which the mTORC1 pathway has been selectively disrupted in cerebellar neurons called Purkinje cells (PCs), the mice show numerous behaviors that are consistent with symptoms of autism.

More than 100 genes have been associated with autism, but one challenge is to understand how gene mutations alter signaling between neurons to cause deficient social interaction, communication and repetitive behaviors. Partha Mitra, Josh Huang and their colleagues at Cold Spring Harbor Laboratory in New York propose to use systematic and large-scale techniques to develop a detailed neuroanatomical map in mouse models of autism.

The cerebellum is a brain region that performs multisensory processing to guide movement and cognition. Although autism spectrum disorders are associated with structural abnormalities and deficiencies in the number and appearance of cells in the cerebellum, cerebellar function in autism has not yet been rigorously characterized.

One of the core symptoms of autism spectrum disorders is impaired social interactions. One reason for this may be that individuals with autism do not experience the typical rewarding aspects of social interactions. There are specific brain areas that are critical for experiencing normal pleasures and specific chemicals in the brain that are thought to be important for promoting social interactions.

Normal behavior requires that brain regions interact with one another, and these interactions depend on the task; they change as attention shifts and as an action is planned and executed. Jonathan Victor and his colleagues at Weill Cornell Medical College in New York have developed a new technology to delineate these moment‐to‐moment changes in brain activity patterns so that they can be compared between typically developing children and those with autism.

Pavel Osten and his colleagues at Cold Spring Harbor Laboratory in New York study mouse brain circuits mediating social and other innate behaviors, such as aggression and sexual behaviors. The researchers use a novel automated whole-mount microscopy method called serial two-photon tomography and computational whole-brain analysis of the induction of the immediate early gene c‐FOS, a molecular marker of neuronal activation. This method allows them to map brain circuits mediating behaviors in control mice. It also enables them to identify brain circuit deficits that may underlie abnormal behaviors in genetic mouse models of autism.

In recent years, autism heritability has been the focus of intense research, and a number of autism susceptibility genes and loci have been identified. This progress has allowed researchers to generate mouse models that carry relevant mutations, providing a biological system for dissecting the circuit, cellular and molecular mechanisms underlying autism-associated changes in brain development.