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1.  Neural Correlates of Direct and Reflected Self-Appraisals in Adolescents and Adults: When Social Perspective-Taking Informs Self-Perception 
Child development  2009;80(4):1016-1038.
Classic theories of self-development suggest people define themselves in part through internalized perceptions of other people’s beliefs about them, known as reflected self-appraisals. This study uses functional magnetic resonance imaging to compare the neural correlates of direct and reflected self-appraisals in adolescence (N = 12, ages 11–14 years) and adulthood (N = 12, ages 23–30 years). During direct self-reflection, adolescents demonstrated greater activity than adults in networks relevant to self-perception (medial prefrontal and parietal cortices) and social-cognition (dorsomedial prefrontal cortex, temporal–parietal junction, and posterior superior temporal sulcus), suggesting adolescent self-construals may rely more heavily on others’ perspectives about the self. Activity in the medial fronto-parietal network was also enhanced when adolescents took the perspective of someone more relevant to a given domain.
doi:10.1111/j.1467-8624.2009.01314.x
PMCID: PMC3229828  PMID: 19630891
2.  Language network dysfunction as a predictor of outcome in youth at clinical high-risk for psychosis 
Schizophrenia research  2009;116(2-3):173.
Objectives
Language processing abnormalities are a hallmark feature of schizophrenia. Yet, no study to date has investigated underlying neural networks associated with discourse processing in adolescents at clinical high risk (CHR) for developing psychosis.
Methods
Forty CHR youth and 24 demographically comparable healthy controls underwent functional magnetic resonance imaging while performing a naturalistic discourse processing paradigm. We assessed differences in blood oxygenation level-dependent (BOLD) activity between task conditions (Topic Maintenance vs. Reasoning) and between groups. Furthermore, we examined the association of regional brain activity with symptom severity and social outcome at follow-up, 6 to 24 months after the scan.
Results
Relative to controls, CHR participants showed increased neural activity in a network of language-associated brain regions, including the medial prefrontal cortex bilaterally, left inferior frontal (LIFG; BA44/45, 47) and middle temporal gyri, and the anterior cingulate (BA24&32). Further, increased activity in the superior temporal gyrus (STG), caudate, and LIFG distinguished those who subsequently developed psychosis. Within the CHR sample, severity of positive formal thought disorder at follow-up was positively correlated with signal change in the LIFG, superior frontal gyrus, and inferior/middle temporal gyri, whereas social outcome was inversely correlated with signal change in the LIFG and anterior cingulate.
Conclusions
These findings are consistent with a neural inefficiency hypothesis in those at greatest risk for psychosis, and additionally suggest that baseline activation differences may predict symptomatic and functional outcome. These results highlight the need to further investigate the neural systems involved in conversion to psychosis, and how language disruption changes over time in at-risk adolescents.
doi:10.1016/j.schres.2009.09.042
PMCID: PMC2818263  PMID: 19861234
fMRI; schizophrenia; inferior frontal gyrus; psychosis prodrome; discourse; functional neuroimaging
3.  Relationships between Brain Activation and Brain Structure in Normally Developing Children 
Cerebral Cortex (New York, NY)  2009;19(11):2595-2604.
Dynamic changes in brain structure, activation, and cognitive abilities co-occur during development, but little is known about how changes in brain structure relate to changes in cognitive function or brain activity. By using cortical pattern matching techniques to correlate cortical gray matter thickness and functional brain activity over the entire brain surface in 24 typically developing children, we integrated structural and functional magnetic resonance imaging data with cognitive test scores to identify correlates of mature performance during orthographic processing. Fast-naming individuals activated the right fronto-parietal attention network in response to novel fonts more than slow-naming individuals, and increased activation of this network was correlated with more mature brain morphology in the same fronto-parietal region. These relationships remained even after effects of age or general cognitive ability were statistically controlled. These results localized cortical regions where mature morphology corresponds to mature patterns of activation, and may suggest a role for experience in mediating brain structure–activation relationships.
doi:10.1093/cercor/bhp011
PMCID: PMC2758677  PMID: 19240138
attention; fMRI; imaging; language; morphometry
4.  Neural correlates of social exclusion during adolescence: understanding the distress of peer rejection 
Developmental research has demonstrated the harmful effects of peer rejection during adolescence; however, the neural mechanisms responsible for this salience remain unexplored. In this study, 23 adolescents were excluded during a ball-tossing game in which they believed they were playing with two other adolescents during an fMRI scan; in reality, participants played with a preset computer program. Afterwards, participants reported their exclusion-related distress and rejection sensitivity, and parents reported participants’ interpersonal competence. Similar to findings in adults, during social exclusion adolescents displayed insular activity that was positively related to self-reported distress, and right ventrolateral prefrontal activity that was negatively related to self-reported distress. Findings unique to adolescents indicated that activity in the subgenual anterior cingulate cortex (subACC) related to greater distress, and that activity in the ventral striatum related to less distress and appeared to play a role in regulating activity in the subACC and other regions involved in emotional distress. Finally, adolescents with higher rejection sensitivity and interpersonal competence scores displayed greater neural evidence of emotional distress, and adolescents with higher interpersonal competence scores also displayed greater neural evidence of regulation, perhaps suggesting that adolescents who are vigilant regarding peer acceptance may be most sensitive to rejection experiences.
doi:10.1093/scan/nsp007
PMCID: PMC2686232  PMID: 19470528
peer rejection; adolescence; functional magnetic resonance imaging
5.  Giving Speech a Hand: Gesture Modulates Activity in Auditory Cortex During Speech Perception 
Human brain mapping  2009;30(3):1028-1037.
Viewing hand gestures during face-to-face communication affects speech perception and comprehension. Despite the visible role played by gesture in social interactions, relatively little is known about how the brain integrates hand gestures with co-occurring speech. Here we used functional magnetic resonance imaging (fMRI) and an ecologically valid paradigm to investigate how beat gesture – a fundamental type of hand gesture that marks speech prosody – might impact speech perception at the neural level. Subjects underwent fMRI while listening to spontaneously-produced speech accompanied by beat gesture, nonsense hand movement, or a still body; as additional control conditions, subjects also viewed beat gesture, nonsense hand movement, or a still body all presented without speech. Validating behavioral evidence that gesture affects speech perception, bilateral nonprimary auditory cortex showed greater activity when speech was accompanied by beat gesture than when speech was presented alone. Further, the left superior temporal gyrus/sulcus showed stronger activity when speech was accompanied by beat gesture than when speech was accompanied by nonsense hand movement. Finally, the right planum temporale was identified as a putative multisensory integration site for beat gesture and speech (i.e., here activity in response to speech accompanied by beat gesture was greater than the summed responses to speech alone and beat gesture alone), indicating that this area may be pivotally involved in synthesizing the rhythmic aspects of both speech and gesture. Taken together, these findings suggest a common neural substrate for processing speech and gesture, likely reflecting their joint communicative role in social interactions.
doi:10.1002/hbm.20565
PMCID: PMC2644740  PMID: 18412134
gestures; speech perception; auditory cortex; magnetic resonance imaging; nonverbal communication

Results 1-5 (5)