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1.  No Neural Evidence of Statistical Learning During Exposure to Artificial Languages in Children with Autism Spectrum Disorders 
Biological psychiatry  2010;68(4):345-351.
Background
Language delay is a hallmark feature of autism spectrum disorders (ASD). The identification of word boundaries in continuous speech is a critical first step in language acquisition that can be accomplished via statistical learning and reliance on speech cues. Importantly, early word segmentation skills have been shown to predict later language development in typically developing (TD) children.
Methods
Here we investigated the neural correlates of online word segmentation in children with and without ASD with a well-established behavioral paradigm previously validated for functional magnetic resonance imaging. Eighteen high-functioning boys with ASD and 18 age- and IQ-matched TD boys underwent functional magnetic resonance imaging while listening to two artificial languages (containing statistical or statistical + prosodic cues to word boundaries) and a random speech stream.
Results
Consistent with prior findings, in TD control subjects, activity in fronto-temporal-parietal networks decreased as the number of cues to word boundaries increased. The ASD children, however, did not show this facilitatory effect. Furthermore, statistical contrasts modeling changes in activity over time identified significant learning-related signal increases for both artificial languages in basal ganglia and left temporo-parietal cortex only in TD children. Finally, the level of communicative impairment in ASD children was inversely correlated with signal increases in these same regions during exposure to the artificial languages.
Conclusions
This is the first study to demonstrate significant abnormalities in the neural architecture subserving language-related learning in ASD children and to link the communicative impairments observed in this population to decreased sensitivity to the statistical and speech cues available in the language input.
doi:10.1016/j.biopsych.2010.01.011
PMCID: PMC3229830  PMID: 20303070
Autism; implicit learning; language; neuroimaging; speech perception
2.  The Neural Basis of Speech Parsing in Children and Adults 
Developmental science  2010;13(2):385-406.
Word segmentation, detecting word boundaries in continuous speech, is a fundamental aspect of language learning that can occur solely by the computation of statistical and speech cues. Fifty-four children underwent functional magnetic resonance imaging (fMRI) while listening to three streams of concatenated syllables, which contained either high statistical regularities, high statistical regularities and speech cues, or no easily-detectable cues. Significant signal increases over time in temporal cortices suggest that children utilized the cues to implicitly segment the speech streams. This was confirmed by the findings of a second fMRI run where children displayed reliably greater activity in left inferior frontal gyrus when listening to ‘words’ that occurred more frequently in the streams of speech they just heard. Finally, comparisons between activity observed in these children vs. previously-studied adults indicate significant developmental changes in the neural substrate of speech parsing.
doi:10.1111/j.1467-7687.2009.00895.x
PMCID: PMC3229831  PMID: 20136936
fMRI; language; development; speech perception; word segmentation; statistical learning
3.  Witnessing peer rejection during early adolescence: Neural correlates of empathy for experiences of social exclusion 
Social neuroscience  2010;5(5-6):496-507.
Neuroimaging studies with adults have begun to reveal the neural bases of empathy; however, this research has focused on empathy for physical pain, rather than empathy for negative social experiences. Moreover, this work has not examined adolescents who may frequently witness and empathize with others who experience negative social experiences like peer rejection. Here, we examined neural activity among early adolescents observing social exclusion compared to observing inclusion, and how this activity related to both trait empathy and subsequent prosocial behavior. Participants were scanned while they observed an individual whom they believed was being socially excluded. At least one day prior to the scan they reported their trait empathy, and following the scan they wrote emails to the excluded victim that were rated for prosocial behavior (e.g., helping, comforting). Observing exclusion compared to inclusion activated regions involved in mentalizing (i.e., dorsomedial prefrontal cortex; DMPFC), particularly among highly empathic individuals. Additionally, individuals who displayed more activity in affective, pain-related regions during observed exclusion compared to inclusion subsequently wrote more prosocial emails to excluded victims. Overall findings suggest that when early adolescents witness social exclusion in their daily lives, some may actually ‘feel the pain’ of the victims and act more prosocially toward them as a result.
doi:10.1080/17470919.2010.490673
PMCID: PMC2957502  PMID: 20602283
adolescence; empathy; peer rejection; social exclusion; functional magnetic resonance imaging
4.  Culture and neuroscience: additive or synergistic? 
The investigation of cultural phenomena using neuroscientific methods—cultural neuroscience (CN)—is receiving increasing attention. Yet it is unclear whether the integration of cultural study and neuroscience is merely additive, providing additional evidence of neural plasticity in the human brain, or truly synergistic, yielding discoveries that neither discipline could have achieved alone. We discuss how the parent fields to CN: cross-cultural psychology, psychological anthropology and cognitive neuroscience inform the investigation of the role of cultural experience in shaping the brain. Drawing on well-established methodologies from cross-cultural psychology and cognitive neuroscience, we outline a set of guidelines for CN, evaluate 17 CN studies in terms of these guidelines, and provide a summary table of our results. We conclude that the combination of culture and neuroscience is both additive and synergistic; while some CN methodologies and findings will represent the direct union of information from parent fields, CN studies employing the methodological rigor required by this logistically challenging new field have the potential to transform existing methodologies and produce unique findings.
doi:10.1093/scan/nsp058
PMCID: PMC2894662  PMID: 20083533
cross-cultural; cross disciplinary; cultural-neuroscience; culture; neuroscience; neuroimaging
5.  Reward Processing in Autism 
The social motivation hypothesis of autism posits that infants with autism do not experience social stimuli as rewarding, thereby leading to a cascade of potentially negative consequences for later development. While possible downstream effects of this hypothesis such as altered face and voice processing have been examined, there has not been a direct investigation of social reward processing in autism. Here we use functional magnetic resonance imaging to examine social and monetary rewarded implicit learning in children with and without autism spectrum disorders (ASD). Sixteen males with ASD and sixteen age- and IQ-matched typically developing (TD) males were scanned while performing two versions of a rewarded implicit learning task. In addition to examining responses to reward, we investigated the neural circuitry supporting rewarded learning and the relationship between these factors and social development. We found diminished neural responses to both social and monetary rewards in ASD, with a pronounced reduction in response to social rewards (SR). Children with ASD also demonstrated a further deficit in frontostriatal response during social, but not monetary, rewarded learning. Moreover, we show a relationship between ventral striatum activity and social reciprocity in TD children. Together, these data support the hypothesis that children with ASD have diminished neural responses to SR, and that this deficit relates to social learning impairments.
doi:10.1002/aur.122
PMCID: PMC3076289  PMID: 20437601
functional MRI (fMRI); social cognition; reward; learning
6.  Altered Functional Connectivity in Frontal Lobe Circuits Is Associated with Variation in the Autism Risk Gene CNTNAP2 
Science translational medicine  2010;2(56):56ra80.
Genetic studies are rapidly identifying variants that shape risk for disorders of human cognition, but the question of how such variants predispose to neuropsychiatric disease remains. Noninvasive human brain imaging allows assessment of the brain in vivo, and the combination of genetics and imaging phenotypes remains one of the only ways to explore functional genotype-phenotype associations in human brain. Common variants in contactin-associated protein-like 2 (CNTNAP2), a neurexin superfamily member, have been associated with several allied neurodevelopmental disorders, including autism and specific language impairment, and CNTNAP2 is highly expressed in frontal lobe circuits in the developing human brain. Using functional neuroimaging, we have demonstrated a relationship between frontal lobar connectivity and common genetic variants in CNTNAP2. These data provide a mechanistic link between specific genetic risk for neurodevelopmental disorders and empirical data implicating dysfunction of long-range connections within the frontal lobe in autism. The convergence between genetic findings and cognitive-behavioral models of autism provides evidence that genetic variation at CNTNAP2 predisposes to diseases such asautism in part through modulation of frontal lobe connectivity.
doi:10.1126/scitranslmed.3001344
PMCID: PMC3065863  PMID: 21048216
7.  Behavioral Profiles of Affected and Unaffected Siblings of Children with Autism: Contribution of Measures of Mother–Infant Interaction and Nonverbal Communication 
We investigated whether deficits in social gaze and affect and in joint attention behaviors are evident within the first year of life among siblings of children with autism who go on to be diagnosed with autism or ASD (ASD) and siblings who are non-diagnosed (NoASD-sib) compared to low-risk controls. The ASD group did not differ from the other two groups at 6 months of age in the frequency of gaze, smiles, and vocalizations directed toward the caregiver, nor in their sensitivity to her withdrawal from interaction. However, by 12 months, infants in the ASD group exhibited lower rates of joint attention and requesting behaviors. In contrast, NoASD-sibs did not differ from comparison infants on any variables of interest at 6 and 12 months.
doi:10.1007/s10803-010-1051-6
PMCID: PMC3044086  PMID: 20568002
Autism; Broader autism phenotype; Early identification; Mother–infant interaction; Still face procedure; Nonverbal communication

Results 1-7 (7)