Lucina Uddin | University of Miami (original) (raw)
Papers by Lucina Uddin
Neuroimage, Jan 1, 2010
Functional and structural maturation of networks comprised of discrete regions is an important as... more Functional and structural maturation of networks comprised of discrete regions is an important aspect of brain development. The default-mode network (DMN) is a prominent network which includes the posterior cingulate cortex (PCC), medial prefrontal cortex (mPFC), medial temporal lobes (MTL), and angular gyrus (AG). Despite increasing interest in DMN function, little is known about its maturation from childhood to adulthood. Here we examine developmental changes in DMN connectivity using a multimodal imaging approach by combining resting-state fMRI, voxel-based morphometry and diffusion tensor imaging-based tractography. We found that the DMN undergoes significant developmental changes in functional and structural connectivity, but these changes are not uniform across all DMN nodes. Convergent structural and functional connectivity analyses suggest that PCC-mPFC connectivity along the cingulum bundle is the most immature link in the DMN of children. Both PCC and mPFC also showed gray matter volume differences, as well as prominent macrostructural and microstructural differences in the dorsal cingulum bundle linking these regions. Notably, structural connectivity between PCC and left MTL was either weak or non-existent in children, even though functional connectivity did not differ from that of adults. These results imply that functional connectivity in children can reach adult-like levels despite weak structural connectivity. We propose that maturation of PCC-mPFC structural connectivity plays an important role in the development of self-related and social-cognitive functions that emerge during adolescence. More generally, our study demonstrates how quantitative multimodal analysis of anatomy and connectivity allows us to better characterize the heterogeneous development and maturation of brain networks.
Trends in Cognitive Sciences, Jan 4, 2007
Consciousness and Cognition, Mar 31, 2011
Over the past several years, the study of self-related cognition has garnered increasing interest... more Over the past several years, the study of self-related cognition has garnered increasing interest amongst psychologists and cognitive neuroscientists. Concomitantly, lesion and neuroimaging studies have demonstrated the importance of intact cortico-cortical and cortico-subcortical connections for supporting high-level cognitive functions. Commissurotomy or "split-brain" patients provide unique insights into the role of the cerebral commissures in maintaining an individual's sense of self, as well as into the unique self-representation capabilities of each cerebral hemisphere. Here we review empirical work examining the integrity of self-related processes in patients with various disconnection syndromes, focusing on studies of self-recognition, ownership, and agency. Taken together, this body of work suggests that an intact corpus callosum enabling interhemispheric transfer is necessary for some, but not all types of self-representations.
Http Dx Doi Org 10 1080 13554794 2010 509320, Jan 4, 2011
Autism Research, 2015
There is a general consensus that autism spectrum disorder (ASD) is accompanied by alterations in... more There is a general consensus that autism spectrum disorder (ASD) is accompanied by alterations in brain connectivity. Much of the neuroimaging work has focused on assessing long-range connectivity disruptions in ASD. However, evidence from both animal models and postmortem examination of the human brain suggests that local connections may also be disrupted in individuals with the disorder. Here, we investigated how regional homogeneity (ReHo), a measure of similarity of a voxel's timeseries to its nearest neighbors, varies across age in individuals with ASD and typically developing (TD) individuals using a cross-sectional design. Resting-state fMRI data obtained from a publicly available database were analyzed to determine group differences in ReHo between three age cohorts: children, adolescents, and adults. In typical development, ReHo across the entire brain was higher in children than in adolescents and adults. In contrast, children with ASD exhibited marginally lower ReHo than TD children, while adolescents and adults with ASD exhibited similar levels of local connectivity as age-matched neurotypical individuals. During all developmental stages, individuals with ASD exhibited lower local connectivity in sensory processing brain regions and higher local connectivity in complex information processing regions. Further, higher local connectivity in ASD corresponded to more severe ASD symptomatology. These results demonstrate that local connectivity is disrupted in ASD across development, with the most pronounced differences occurring in childhood. Developmental changes in ReHo do not mirror findings from fMRI studies of long-range connectivity in ASD, pointing to a need for more nuanced accounts of brain connectivity alterations in the disorder. Autism Res 2015. © 2015 International Society for Autism Research, Wiley Periodicals, Inc.
Neuroscience & Biobehavioral Reviews, 2015
Apathy remains a common neuropsychiatric disturbance in the Human Immunodeficiency Virus (HIV-1) ... more Apathy remains a common neuropsychiatric disturbance in the Human Immunodeficiency Virus (HIV-1) despite advances in anti-retroviral treatment (ART). The goal of the current review is to recapitulate findings relating apathy to the deleterious biobehavioral effects of HIV-1 in the post-ART era. Available literatures demonstrate that the emergence of apathy with other neurocognitive and neuropsychiatric symptoms may be attributed to neurotoxic effects of viral proliferation, e.g., aggregative effect of Tat and gp120 on apoptosis, transport and other enzymatic reactions amongst dopaminergic neurons and neuroglia. An assortment of neuroimaging modalities converge on the severity of apathy symptoms associated with the propensity of the virus to replicate within frontal-striatal brain circuits that facilitate emotional processing. Burgeoning research into functional brain connectivity also supports the effects of microvascular and neuro-inflammatory injury linked to aging with HIV-1 on the presentation of neuropsychiatric symptoms. Summarizing these findings, we review domains of HIV-associated neurocognitive and neuropsychiatric impairment linked to apathy in HIV. Taken together, these lines of research suggest that loss of affective, cognitive and behavioral inertia is commensurate with the neuropathology of HIV-1.
NeuroImage. Clinical, 2015
Disrupted cortical connectivity is thought to underlie the complex cognitive and behavior profile... more Disrupted cortical connectivity is thought to underlie the complex cognitive and behavior profile observed in individuals with autism spectrum disorder (ASD). Previous neuroimaging research has identified patterns of both functional hypo- and hyper-connectivity in individuals with ASD. A recent theory attempting to reconcile conflicting results in the literature proposes that hyper-connectivity of brain networks may be more characteristic of young children with ASD, while hypo-connectivity may be more prevalent in adolescents and adults with the disorder when compared to typical development (TD) (Uddin etal., 2013). Previous work has examined only young children, mixed groups of children and adolescents, or adult cohorts in separate studies, leaving open the question of developmental influences on functional brain connectivity in ASD. The current study tests this developmental hypothesis by examining within- and between-network resting state functional connectivity in a large sample...
Trends in neurosciences, 2015
Hahamy and colleagues demonstrate individualized alterations of functional connectivity in the br... more Hahamy and colleagues demonstrate individualized alterations of functional connectivity in the brains of adults with autism, suggesting that previous characterizations of general under- or over-connectivity may be overly simplistic. Adopting a developmental perspective spanning both cortical and subcortical landscapes will further clarify the nature and extent of these atypicalities.
Neuropsychologia, Jan 28, 2015
Autism spectrum disorder (ASD) is characterized by reduced attention to social stimuli including ... more Autism spectrum disorder (ASD) is characterized by reduced attention to social stimuli including the human face. This hypo-responsiveness to stimuli that are engaging to typically developing individuals may result from dysfunctioning motivation, reward, and attention systems in the brain. Here we review an emerging neuroimaging literature that emphasizes a shift from focusing on hypo-activation of isolated brain regions such as the fusiform gyrus, amygdala, and superior temporal sulcus in ASD to a more holistic approach to understanding face perception as a process supported by distributed cortical and subcortical brain networks. We summarize evidence for atypical activation patterns within brain networks that may contribute to social deficits characteristic of the disorder. We conclude by pointing to gaps in the literature and future directions that will continue to shed light on aspects of face processing in autism that are still under-examined. In particular, we highlight the nee...
Nature reviews. Neuroscience, 2015
The brain is constantly bombarded by stimuli, and the relative salience of these inputs determine... more The brain is constantly bombarded by stimuli, and the relative salience of these inputs determines which are more likely to capture attention. A brain system known as the 'salience network', with key nodes in the insular cortices, has a central role in the detection of behaviourally relevant stimuli and the coordination of neural resources. Emerging evidence suggests that atypical engagement of specific subdivisions of the insula within the salience network is a feature of many neuropsychiatric disorders.
Physics of life reviews, 2014
Frontiers in Human Neuroscience, 2013
Recent evidence for the fractionation of the default mode network (DMN) into functionally disting... more Recent evidence for the fractionation of the default mode network (DMN) into functionally distinguishable subdivisions with unique patterns of connectivity calls for a reconceptualization of the relationship between this network and self-referential processing. Advances in resting-state functional connectivity analyses are beginning to reveal increasingly complex patterns of organization within the key nodes of the DMN - medial prefrontal cortex and posterior cingulate cortex - as well as between these nodes and other brain systems. Here we review recent examinations of the relationships between the DMN and various aspects of self-relevant and social-cognitive processing in light of emerging evidence for heterogeneity within this network. Drawing from a rapidly evolving social-cognitive neuroscience literature, we propose that embodied simulation and mentalizing are processes which allow us to gain insight into another's physical and mental state by providing privileged access to our own physical and mental states. Embodiment implies that the same neural systems are engaged for self- and other-understanding through a simulation mechanism, while mentalizing refers to the use of high-level conceptual information to make inferences about the mental states of self and others. These mechanisms work together to provide a coherent representation of the self and by extension, of others. Nodes of the DMN selectively interact with brain systems for embodiment and mentalizing, including the mirror neuron system, to produce appropriate mappings in the service of social-cognitive demands.
Handbooks of Sociology and Social Research, 2012
Frontiers in Human Neuroscience, Nov 24, 2009
Poor mathematical abilities adversely affect academic and career opportunities. The neuroanatomic... more Poor mathematical abilities adversely affect academic and career opportunities. The neuroanatomical basis of developmental dyscalculia (DD), a specific learning deficit with prevalence rates exceeding 5%, is poorly understood. We used structural MRI and diffusion tensor imaging (DTI) to examine macro-and micro-structural impairments in 7-to 9-year-old children with DD, compared to a group of typically developing (TD) children matched on age, gender, intelligence, reading abilities and working memory capacity. Voxel-based ...
Frontiers in Human Neuroscience, 2014
Frontiers in Human Neuroscience, 2013
While there is almost universal agreement amongst researchers that autism is associated with alte... more While there is almost universal agreement amongst researchers that autism is associated with alterations in brain connectivity, the precise nature of these alterations continues to be debated. Theoretical and empirical work is beginning to reveal that autism is associated with a complex functional phenotype characterized by both hypo- and hyper-connectivity of large-scale brain systems. It is not yet understood why such conflicting patterns of brain connectivity are observed across different studies, and the factors contributing to these heterogeneous findings have not been identified. Developmental changes in functional connectivity have received inadequate attention to date. We propose that discrepancies between findings of autism related hypo-connectivity and hyper-connectivity might be reconciled by taking developmental changes into account. We review neuroimaging studies of autism, with an emphasis on functional magnetic resonance imaging studies of intrinsic functional connectivity in children, adolescents and adults. The consistent pattern emerging across several studies is that while intrinsic functional connectivity in adolescents and adults with autism is generally reduced compared with age-matched controls, functional connectivity in younger children with the disorder appears to be increased. We suggest that by placing recent empirical findings within a developmental framework, and explicitly characterizing age and pubertal stage in future work, it may be possible to resolve conflicting findings of hypo- and hyper-connectivity in the extant literature and arrive at a more comprehensive understanding of the neurobiology of autism.
Neuroimage, Jan 1, 2010
Functional and structural maturation of networks comprised of discrete regions is an important as... more Functional and structural maturation of networks comprised of discrete regions is an important aspect of brain development. The default-mode network (DMN) is a prominent network which includes the posterior cingulate cortex (PCC), medial prefrontal cortex (mPFC), medial temporal lobes (MTL), and angular gyrus (AG). Despite increasing interest in DMN function, little is known about its maturation from childhood to adulthood. Here we examine developmental changes in DMN connectivity using a multimodal imaging approach by combining resting-state fMRI, voxel-based morphometry and diffusion tensor imaging-based tractography. We found that the DMN undergoes significant developmental changes in functional and structural connectivity, but these changes are not uniform across all DMN nodes. Convergent structural and functional connectivity analyses suggest that PCC-mPFC connectivity along the cingulum bundle is the most immature link in the DMN of children. Both PCC and mPFC also showed gray matter volume differences, as well as prominent macrostructural and microstructural differences in the dorsal cingulum bundle linking these regions. Notably, structural connectivity between PCC and left MTL was either weak or non-existent in children, even though functional connectivity did not differ from that of adults. These results imply that functional connectivity in children can reach adult-like levels despite weak structural connectivity. We propose that maturation of PCC-mPFC structural connectivity plays an important role in the development of self-related and social-cognitive functions that emerge during adolescence. More generally, our study demonstrates how quantitative multimodal analysis of anatomy and connectivity allows us to better characterize the heterogeneous development and maturation of brain networks.
Trends in Cognitive Sciences, Jan 4, 2007
Consciousness and Cognition, Mar 31, 2011
Over the past several years, the study of self-related cognition has garnered increasing interest... more Over the past several years, the study of self-related cognition has garnered increasing interest amongst psychologists and cognitive neuroscientists. Concomitantly, lesion and neuroimaging studies have demonstrated the importance of intact cortico-cortical and cortico-subcortical connections for supporting high-level cognitive functions. Commissurotomy or "split-brain" patients provide unique insights into the role of the cerebral commissures in maintaining an individual's sense of self, as well as into the unique self-representation capabilities of each cerebral hemisphere. Here we review empirical work examining the integrity of self-related processes in patients with various disconnection syndromes, focusing on studies of self-recognition, ownership, and agency. Taken together, this body of work suggests that an intact corpus callosum enabling interhemispheric transfer is necessary for some, but not all types of self-representations.
Http Dx Doi Org 10 1080 13554794 2010 509320, Jan 4, 2011
Autism Research, 2015
There is a general consensus that autism spectrum disorder (ASD) is accompanied by alterations in... more There is a general consensus that autism spectrum disorder (ASD) is accompanied by alterations in brain connectivity. Much of the neuroimaging work has focused on assessing long-range connectivity disruptions in ASD. However, evidence from both animal models and postmortem examination of the human brain suggests that local connections may also be disrupted in individuals with the disorder. Here, we investigated how regional homogeneity (ReHo), a measure of similarity of a voxel's timeseries to its nearest neighbors, varies across age in individuals with ASD and typically developing (TD) individuals using a cross-sectional design. Resting-state fMRI data obtained from a publicly available database were analyzed to determine group differences in ReHo between three age cohorts: children, adolescents, and adults. In typical development, ReHo across the entire brain was higher in children than in adolescents and adults. In contrast, children with ASD exhibited marginally lower ReHo than TD children, while adolescents and adults with ASD exhibited similar levels of local connectivity as age-matched neurotypical individuals. During all developmental stages, individuals with ASD exhibited lower local connectivity in sensory processing brain regions and higher local connectivity in complex information processing regions. Further, higher local connectivity in ASD corresponded to more severe ASD symptomatology. These results demonstrate that local connectivity is disrupted in ASD across development, with the most pronounced differences occurring in childhood. Developmental changes in ReHo do not mirror findings from fMRI studies of long-range connectivity in ASD, pointing to a need for more nuanced accounts of brain connectivity alterations in the disorder. Autism Res 2015. © 2015 International Society for Autism Research, Wiley Periodicals, Inc.
Neuroscience & Biobehavioral Reviews, 2015
Apathy remains a common neuropsychiatric disturbance in the Human Immunodeficiency Virus (HIV-1) ... more Apathy remains a common neuropsychiatric disturbance in the Human Immunodeficiency Virus (HIV-1) despite advances in anti-retroviral treatment (ART). The goal of the current review is to recapitulate findings relating apathy to the deleterious biobehavioral effects of HIV-1 in the post-ART era. Available literatures demonstrate that the emergence of apathy with other neurocognitive and neuropsychiatric symptoms may be attributed to neurotoxic effects of viral proliferation, e.g., aggregative effect of Tat and gp120 on apoptosis, transport and other enzymatic reactions amongst dopaminergic neurons and neuroglia. An assortment of neuroimaging modalities converge on the severity of apathy symptoms associated with the propensity of the virus to replicate within frontal-striatal brain circuits that facilitate emotional processing. Burgeoning research into functional brain connectivity also supports the effects of microvascular and neuro-inflammatory injury linked to aging with HIV-1 on the presentation of neuropsychiatric symptoms. Summarizing these findings, we review domains of HIV-associated neurocognitive and neuropsychiatric impairment linked to apathy in HIV. Taken together, these lines of research suggest that loss of affective, cognitive and behavioral inertia is commensurate with the neuropathology of HIV-1.
NeuroImage. Clinical, 2015
Disrupted cortical connectivity is thought to underlie the complex cognitive and behavior profile... more Disrupted cortical connectivity is thought to underlie the complex cognitive and behavior profile observed in individuals with autism spectrum disorder (ASD). Previous neuroimaging research has identified patterns of both functional hypo- and hyper-connectivity in individuals with ASD. A recent theory attempting to reconcile conflicting results in the literature proposes that hyper-connectivity of brain networks may be more characteristic of young children with ASD, while hypo-connectivity may be more prevalent in adolescents and adults with the disorder when compared to typical development (TD) (Uddin etal., 2013). Previous work has examined only young children, mixed groups of children and adolescents, or adult cohorts in separate studies, leaving open the question of developmental influences on functional brain connectivity in ASD. The current study tests this developmental hypothesis by examining within- and between-network resting state functional connectivity in a large sample...
Trends in neurosciences, 2015
Hahamy and colleagues demonstrate individualized alterations of functional connectivity in the br... more Hahamy and colleagues demonstrate individualized alterations of functional connectivity in the brains of adults with autism, suggesting that previous characterizations of general under- or over-connectivity may be overly simplistic. Adopting a developmental perspective spanning both cortical and subcortical landscapes will further clarify the nature and extent of these atypicalities.
Neuropsychologia, Jan 28, 2015
Autism spectrum disorder (ASD) is characterized by reduced attention to social stimuli including ... more Autism spectrum disorder (ASD) is characterized by reduced attention to social stimuli including the human face. This hypo-responsiveness to stimuli that are engaging to typically developing individuals may result from dysfunctioning motivation, reward, and attention systems in the brain. Here we review an emerging neuroimaging literature that emphasizes a shift from focusing on hypo-activation of isolated brain regions such as the fusiform gyrus, amygdala, and superior temporal sulcus in ASD to a more holistic approach to understanding face perception as a process supported by distributed cortical and subcortical brain networks. We summarize evidence for atypical activation patterns within brain networks that may contribute to social deficits characteristic of the disorder. We conclude by pointing to gaps in the literature and future directions that will continue to shed light on aspects of face processing in autism that are still under-examined. In particular, we highlight the nee...
Nature reviews. Neuroscience, 2015
The brain is constantly bombarded by stimuli, and the relative salience of these inputs determine... more The brain is constantly bombarded by stimuli, and the relative salience of these inputs determines which are more likely to capture attention. A brain system known as the 'salience network', with key nodes in the insular cortices, has a central role in the detection of behaviourally relevant stimuli and the coordination of neural resources. Emerging evidence suggests that atypical engagement of specific subdivisions of the insula within the salience network is a feature of many neuropsychiatric disorders.
Physics of life reviews, 2014
Frontiers in Human Neuroscience, 2013
Recent evidence for the fractionation of the default mode network (DMN) into functionally disting... more Recent evidence for the fractionation of the default mode network (DMN) into functionally distinguishable subdivisions with unique patterns of connectivity calls for a reconceptualization of the relationship between this network and self-referential processing. Advances in resting-state functional connectivity analyses are beginning to reveal increasingly complex patterns of organization within the key nodes of the DMN - medial prefrontal cortex and posterior cingulate cortex - as well as between these nodes and other brain systems. Here we review recent examinations of the relationships between the DMN and various aspects of self-relevant and social-cognitive processing in light of emerging evidence for heterogeneity within this network. Drawing from a rapidly evolving social-cognitive neuroscience literature, we propose that embodied simulation and mentalizing are processes which allow us to gain insight into another's physical and mental state by providing privileged access to our own physical and mental states. Embodiment implies that the same neural systems are engaged for self- and other-understanding through a simulation mechanism, while mentalizing refers to the use of high-level conceptual information to make inferences about the mental states of self and others. These mechanisms work together to provide a coherent representation of the self and by extension, of others. Nodes of the DMN selectively interact with brain systems for embodiment and mentalizing, including the mirror neuron system, to produce appropriate mappings in the service of social-cognitive demands.
Handbooks of Sociology and Social Research, 2012
Frontiers in Human Neuroscience, Nov 24, 2009
Poor mathematical abilities adversely affect academic and career opportunities. The neuroanatomic... more Poor mathematical abilities adversely affect academic and career opportunities. The neuroanatomical basis of developmental dyscalculia (DD), a specific learning deficit with prevalence rates exceeding 5%, is poorly understood. We used structural MRI and diffusion tensor imaging (DTI) to examine macro-and micro-structural impairments in 7-to 9-year-old children with DD, compared to a group of typically developing (TD) children matched on age, gender, intelligence, reading abilities and working memory capacity. Voxel-based ...
Frontiers in Human Neuroscience, 2014
Frontiers in Human Neuroscience, 2013
While there is almost universal agreement amongst researchers that autism is associated with alte... more While there is almost universal agreement amongst researchers that autism is associated with alterations in brain connectivity, the precise nature of these alterations continues to be debated. Theoretical and empirical work is beginning to reveal that autism is associated with a complex functional phenotype characterized by both hypo- and hyper-connectivity of large-scale brain systems. It is not yet understood why such conflicting patterns of brain connectivity are observed across different studies, and the factors contributing to these heterogeneous findings have not been identified. Developmental changes in functional connectivity have received inadequate attention to date. We propose that discrepancies between findings of autism related hypo-connectivity and hyper-connectivity might be reconciled by taking developmental changes into account. We review neuroimaging studies of autism, with an emphasis on functional magnetic resonance imaging studies of intrinsic functional connectivity in children, adolescents and adults. The consistent pattern emerging across several studies is that while intrinsic functional connectivity in adolescents and adults with autism is generally reduced compared with age-matched controls, functional connectivity in younger children with the disorder appears to be increased. We suggest that by placing recent empirical findings within a developmental framework, and explicitly characterizing age and pubertal stage in future work, it may be possible to resolve conflicting findings of hypo- and hyper-connectivity in the extant literature and arrive at a more comprehensive understanding of the neurobiology of autism.