Obsessive–compulsive disorder (OCD) and autism spectrum disorders (ASD) commonly co-occur and are... more Obsessive–compulsive disorder (OCD) and autism spectrum disorders (ASD) commonly co-occur and are considered challenging to manage when they co-occur in youth. However, clinical characteristics and prognosis of this group remain poorly understood. This study examined the prevalence, clinical correlates and outcomes of paediatric OCD co-occurring with ASD (OCD + ASD) in a large clinical cohort. Data were extracted from electronic clinical records of young people aged 4–17 years who had attended a mental health trust in South London, United Kingdom. We identified young people with diagnoses of OCD + ASD (n = 335), OCD without ASD (n = 1010), and ASD without OCD (n = 6577). 25% of youth with OCD had a diagnosis of ASD, while 5% of those with ASD had a diagnosis of OCD. At diagnosis, youth with OCD + ASD had lower psychosocial functioning scores on the clinician-rated Child Global Assessment Scale (CGAS) compared to those with either OCD or ASD. Youth with OCD + ASD were equally likely ...
Obsessive–compulsive disorder (OCD) and autism spectrum disorders (ASD) commonly co-occur and are... more Obsessive–compulsive disorder (OCD) and autism spectrum disorders (ASD) commonly co-occur and are considered challenging to manage when they co-occur in youth. However, clinical characteristics and prognosis of this group remain poorly understood. This study examined the prevalence, clinical correlates and outcomes of paediatric OCD co-occurring with ASD (OCD + ASD) in a large clinical cohort. Data were extracted from electronic clinical records of young people aged 4–17 years who had attended a mental health trust in South London, United Kingdom. We identified young people with diagnoses of OCD + ASD (n = 335), OCD without ASD (n = 1010), and ASD without OCD (n = 6577). 25% of youth with OCD had a diagnosis of ASD, while 5% of those with ASD had a diagnosis of OCD. At diagnosis, youth with OCD + ASD had lower psychosocial functioning scores on the clinician-rated Child Global Assessment Scale (CGAS) compared to those with either OCD or ASD. Youth with OCD + ASD were equally likely ...
Biological psychiatry. Cognitive neuroscience and neuroimaging, 2017
Prevailing theories suggest that autism spectrum disorder (ASD) results from impaired brain commu... more Prevailing theories suggest that autism spectrum disorder (ASD) results from impaired brain communication, causing aberrant synchrony among neuronal populations. However, it remains debated whether synchrony abnormalities are among local or long-range circuits, are circuit specific or are generalized, reflect hypersynchrony or reflect hyposynchrony, and are frequency band-specific or are distributed across the frequency spectrum. To help clarify these unresolved questions, we recorded spontaneous magnetoencephalography data and used a data-driven, whole-brain analysis of frequency-specific interregional synchrony in higher-functioning adolescents and adults, with 17 ASD and 18 control subjects matched on age, IQ, and sex, and equal for motion. Individuals with ASD showed local hypersynchrony in the theta band (4-7 Hz) in the lateral occipitotemporal cortex. Long-range hyposynchrony was seen in the alpha band (10-13 Hz), which was most prominent in neural circuitry underpinning socia...
Journal of autism and developmental disorders, 2018
There is growing evidence of a camouflaging effect among females with autism spectrum disorder (A... more There is growing evidence of a camouflaging effect among females with autism spectrum disorder (ASD), particularly among those without intellectual disability, which may affect performance on gold-standard diagnostic measures. This study utilized an age- and IQ-matched sample of school-aged youth (n = 228) diagnosed with ASD to assess sex differences on the ADOS and ADI-R, parent-reported autistic traits, and adaptive skills. Although females and males were rated similarly on gold-standard diagnostic measures overall, females with higher IQs were less likely to meet criteria on the ADI-R. Females were also found to be significantly more impaired on parent reported autistic traits and adaptive skills. Overall, the findings suggest that some autistic females may be missed by current diagnostic procedures.
Childhood-onset schizophrenia (COS) is a rare, severe form of the adult-onset disorder (AOS). Our... more Childhood-onset schizophrenia (COS) is a rare, severe form of the adult-onset disorder (AOS). Our previous resting-state fMRI study identified attenuated functional connectivity in COS compared with controls. Here, we ask whether COS and AOS patients and their siblings exhibit similar abnormalities of functional connectivity. A whole-brain, data-driven approach was used to assess resting-state functional connectivity differences in COS (patients/siblings/controls, n: 26/28/33) and AOS (n: 19/28/30). There were no significant differences in age, sex, or head motion across groups in each dataset and as designed, the COS dataset has a significantly lower age than the AOS. Both COS and AOS patients showed decreased functional connectivity relative to controls among a wide set of brain regions (P<0.05, corrected), but their siblings did not. Decreased connectivity in COS and AOS patients showed no amplitude differences and was not modulated by age-at-onset or medication doses. Cluster...
Recent findings in monkeys suggest that intrinsic periodic spiking activity in selective cortical... more Recent findings in monkeys suggest that intrinsic periodic spiking activity in selective cortical areas occurs at timescales that follow a sensory or lower order-to-higher order processing hierarchy (Murray JD, Bernacchia A, Freedman DJ, Romo R, Wallis JD, Cai X, Padoa-Schioppa C, Pasternak T, Seo H, Lee D, Wang XJ. Nat Neurosci 17: 1661–1663, 2014). It has not yet been fully explored if a similar timescale hierarchy is present in humans. Additionally, these measures in the monkey studies have not addressed findings that rhythmic activity within a brain area can occur at multiple frequencies. In this study we investigate in humans if regions may be biased toward particular frequencies of intrinsic activity and if a full cortical mapping still reveals an organization that follows this hierarchy. We examined the spectral power in multiple frequency bands (0.5–150 Hz) from task-independent data using magnetoencephalography (MEG). We compared standardized power across bands to find regi...
Head motion can be estimated at any point of fMRI image processing. Processing steps involving te... more Head motion can be estimated at any point of fMRI image processing. Processing steps involving temporal interpolation (e.g., slice time correction or outlier replacement) often precede motion estimation in the literature. From first principles it can be anticipated that temporal interpolation will alter head motion in a scan. Here we demonstrate this effect and its consequences in five large fMRI datasets. Estimated head motion was reduced by 10-50% or more following temporal interpolation, and reductions were often visible to the naked eye. Such reductions make the data seem to be of improved quality. Such reductions also degrade the sensitivity of analyses aimed at detecting motion-related artifact and can cause a dataset with artifact to falsely appear artifact-free. These reduced motion estimates will be particularly problematic for studies needing estimates of motion in time, such as studies of dynamics. Based on these findings, it is sensible to obtain motion estimates prior to any image processing (regardless of subsequent processing steps and the actual timing of motion correction procedures, which need not be changed). We also find that outlier replacement procedures change signals almost entirely during times of motion and therefore have notable similarities to motion-targeting censoring strategies (which withhold or replace signals entirely during times of motion).
The existence of abnormal connectivity patterns between resting state networks in neuropsychiatri... more The existence of abnormal connectivity patterns between resting state networks in neuropsychiatric disorders, including Autism Spectrum Disorder (ASD), has been well established. Traditional treatment methods in ASD are limited, and do not address the aberrant network structure. Using real-time fMRI neurofeedback, we directly trained 3 brain nodes in participants with ASD, in which the aberrant connectivity has been shown to correlate with symptom severity. Desired network connectivity patterns were reinforced in real-time, without participants' awareness of the training taking place. This training regimen produced large, significant long-term changes in correlations at the network level, and whole brain analysis revealed that the greatest changes were focused on the areas being trained. These changes were not found in the control group. Moreover, changes in ASD resting state connectivity following the training were correlated to changes in behavior, suggesting that neurofeedbac...
Journal of autism and developmental disorders, Jan 14, 2017
For individuals with autism spectrum disorder (ASD), long-term outcomes have been troubling, and ... more For individuals with autism spectrum disorder (ASD), long-term outcomes have been troubling, and intact IQ has not been shown to be protective. Nevertheless, relatively little research into adaptive functioning among adults with ASD has been completed to date. Therefore, both adaptive functioning and comorbid psychopathology were assessed among 52 adults with ASD without intellectual disability (ID). Adaptive functioning was found to substantially lag behind IQ, and socialization was a particular weakness. Comorbid psychopathology was significantly correlated with the size of IQ-adaptive functioning discrepancy. These findings emphasize key intervention targets of both adaptive skill and psychopathology for transition-age youth and young adults with ASD, as well as the need for ongoing monitoring of anxiety and depression symptoms during this developmental window.
The homeostatic regulation of feeding behavior requires an organism to be able to integrate infor... more The homeostatic regulation of feeding behavior requires an organism to be able to integrate information from its internal environment, including peripheral visceral signals about the body's current energy needs, with information from its external environment, such as the palatability of energy-rich food stimuli. The insula, which serves as the brain's primary sensory cortex for representing both visceral signals from the body and taste signals from the mouth and tongue, is a likely candidate region in which this integration might occur. However, to date it has been unclear whether information from these two homeostatically critical faculties is merely co-represented in the human insula, or actually integrated there. Recent functional neuroimaging evidence of a common substrate for visceral interoception and taste perception within the human dorsal mid-insula suggests a model whereby a single population of neurons may integrate viscerosensory and gustatory signals. To test th...
Journal of autism and developmental disorders, Feb 23, 2016
Although social-communication difficulties and repetitive behaviors are hallmark features of auti... more Although social-communication difficulties and repetitive behaviors are hallmark features of autism spectrum disorder (ASD) and persist across the lifespan, very few studies have compared age-related differences in these behaviors between youth with ASD and same-age typically developing (TD) peers. We examined this issue using SRS-2 (Social Responsiveness Scale-Second Edition) measures of social-communicative functioning and repetitive behaviors in a stratified cross-sectional sample of 324 youth with ASD in the absence of intellectual disability, and 438 TD youth (aged 4-29 years). An age-by-group interaction emerged indicating that TD youth exhibited age-related improvements in social-communication scores while the ASD group demonstrated age-related declines in these scores. This suggests that adolescents/adults with ASD may fall increasingly behind their same-age peers in social-communicative skills.
The anterior region of the left superior temporal gyrus/superior temporal sulcus (aSTG/STS) has b... more The anterior region of the left superior temporal gyrus/superior temporal sulcus (aSTG/STS) has been implicated in two very different cognitive functions: sentence processing and social-emotional processing. However, the vast majority of the sentence stimuli in previous reports have been of a social or social-emotional nature suggesting that sentence processing may be confounded with semantic content. To evaluate this possibility we had subjects read word lists that differed in phrase/constituent size (single words, 3-word phrases, 6-word sentences) and semantic content (social-emotional, social, and inanimate objects) while scanned in a 7T environment. This allowed us to investigate if the aSTG/STS responded to increasing constituent structure (with increased activity as a function of constituent size) with or without regard to a specific domain of concepts, i.e., social and/or social-emotional content. Activity in the left aSTG/STS was found to increase with constituent size. This...
... Britain 0028 3932 97 17,00+0,00 Automatic semantic priming of nouns and verbs in patients wit... more ... Britain 0028 3932 97 17,00+0,00 Automatic semantic priming of nouns and verbs in patients with Alzheimer's disease CAMILLE M. BUSHELL ... Neely, JH Semantic priming and retrieval from lexical memory: roles ofinhibitionless spreading acti vation and limited capacity attention ...
Journal of autism and developmental disorders, Jan 16, 2015
Although executive functioning (EF) difficulties are well documented among children and adolescen... more Although executive functioning (EF) difficulties are well documented among children and adolescents with autism spectrum disorder (ASD), little is known about real-world measures of EF among adults with ASD. Therefore, this study examined parent-reported real-world EF problems among 35 adults with ASD without intellectual disability and their correlations with adaptive functioning and co-morbid anxiety and depression symptomatology. A variable EF profile was found with prominent deficits occurring in flexibility and metacognition. Flexibility problems were associated with anxiety-related symptoms while metacognition difficulties were associated with depression symptoms and impaired adaptive functioning (though the metacognition-adaptive functioning relationship was moderated by ADHD symptoms). These persistent EF problems are predictors of broader functioning and therefore remain an important treatment target among adults with ASD.
A single exposure to an object can produce long-lasting behavioral change. Here, using event-rela... more A single exposure to an object can produce long-lasting behavioral change. Here, using event-related functional magnetic resonance imaging (fMRI), we provide evidence for long-lasting changes in cortical activity associated with perceiving and naming objects. In posterior regions, we observed an immediate (30-second) and long-lasting (3-day) decrease in neural activity after brief (200-ms) exposure to nameable and nonsense objects. In addition, slower-developing decreases in left inferior frontal activity were observed concurrently with increases in left insula activity, only for nameable objects. These time-dependent cortical changes may reflect two distinct learning mechanisms: the formation of sparser, yet more object-form-specific, representations in posterior regions, and experience-induced reorganization of the brain circuitry underlying lexical retrieval in anterior regions.
One of the most robust and oft-replicated findings in cognitive neuroscience is that several spat... more One of the most robust and oft-replicated findings in cognitive neuroscience is that several spatially distinct, functionally dissociable ventral occipitotemporal cortex (VOTC) regions respond preferentially to different categories of concrete entities. However, the determinants of this category-related organization remain to be fully determined. One recent proposal is that privileged connectivity of these VOTC regions with other regions that store and/or process category-relevant properties may be a major contributing factor. To test this hypothesis, we used a multicategory functional magnetic resonance imaging (MRI) localizer to individually define category-related brain regions of interest (ROIs) in a large group of subjects (n = 33). We then used these ROIs in resting-state functional connectivity MRI analyses to explore spontaneous functional connectivity among these regions. We demonstrate that during rest, distinct category-preferential VOTC regions show differentially strong...
To investigate the functional neuroanatomy associated with retrieving semantic and episodic memor... more To investigate the functional neuroanatomy associated with retrieving semantic and episodic memories\ we measured changes in regional cerebral blood~ow "rCBF# with positron emission tomography "PET# while subjects generated single word responses to achromatic line drawings of objects[ During separate scans\ subjects either named each object\ retrieved a commonly associated color of each object "semantic condition#\ or recalled a previously studied uncommon color of each object "episodic condition#[ Subjects were also scanned while staring at visual noise patterns to provide a low level perceptual baseline[ Relative to the low level baseline\ all three conditions revealed bilateral activations of posterior regions of the temporal lobes\ cerebellum\ and left lateralized activations in frontal regions[ Retrieving semantic information\ as compared to object naming\ activated left inferior temporal\ left superior parietal\ and left frontal cortices[ In addition\ small regions of right frontal cortex were activated[ Retrieving episodic information\ as compared to object naming\ activated bilateral medial parietal cortex\ bilateral retrosplenial cortex\ right frontal cortex\ thalamus\ and cerebellum[ Direct comparison of the semantic and episodic conditions revealed bilateral activation in temporal and frontal lobes in the semantic task "left greater than right#\ and activation in medial parietal cortex\ retrosplenial cortex\ thalamus\ and cerebellum "but not right frontal regions# in the episodic task[ These results support the assertion that distinct neural structures mediate semantic and episodic memory retrieval[ However\ they also raise questions regarding the speci_c roles of left temporal and right frontal cortices during episodic memory retrieval\ in particular[ Þ 0887 Elsevier Science Ltd[ All rights reserved[
Obsessive–compulsive disorder (OCD) and autism spectrum disorders (ASD) commonly co-occur and are... more Obsessive–compulsive disorder (OCD) and autism spectrum disorders (ASD) commonly co-occur and are considered challenging to manage when they co-occur in youth. However, clinical characteristics and prognosis of this group remain poorly understood. This study examined the prevalence, clinical correlates and outcomes of paediatric OCD co-occurring with ASD (OCD + ASD) in a large clinical cohort. Data were extracted from electronic clinical records of young people aged 4–17 years who had attended a mental health trust in South London, United Kingdom. We identified young people with diagnoses of OCD + ASD (n = 335), OCD without ASD (n = 1010), and ASD without OCD (n = 6577). 25% of youth with OCD had a diagnosis of ASD, while 5% of those with ASD had a diagnosis of OCD. At diagnosis, youth with OCD + ASD had lower psychosocial functioning scores on the clinician-rated Child Global Assessment Scale (CGAS) compared to those with either OCD or ASD. Youth with OCD + ASD were equally likely ...
Obsessive–compulsive disorder (OCD) and autism spectrum disorders (ASD) commonly co-occur and are... more Obsessive–compulsive disorder (OCD) and autism spectrum disorders (ASD) commonly co-occur and are considered challenging to manage when they co-occur in youth. However, clinical characteristics and prognosis of this group remain poorly understood. This study examined the prevalence, clinical correlates and outcomes of paediatric OCD co-occurring with ASD (OCD + ASD) in a large clinical cohort. Data were extracted from electronic clinical records of young people aged 4–17 years who had attended a mental health trust in South London, United Kingdom. We identified young people with diagnoses of OCD + ASD (n = 335), OCD without ASD (n = 1010), and ASD without OCD (n = 6577). 25% of youth with OCD had a diagnosis of ASD, while 5% of those with ASD had a diagnosis of OCD. At diagnosis, youth with OCD + ASD had lower psychosocial functioning scores on the clinician-rated Child Global Assessment Scale (CGAS) compared to those with either OCD or ASD. Youth with OCD + ASD were equally likely ...
Biological psychiatry. Cognitive neuroscience and neuroimaging, 2017
Prevailing theories suggest that autism spectrum disorder (ASD) results from impaired brain commu... more Prevailing theories suggest that autism spectrum disorder (ASD) results from impaired brain communication, causing aberrant synchrony among neuronal populations. However, it remains debated whether synchrony abnormalities are among local or long-range circuits, are circuit specific or are generalized, reflect hypersynchrony or reflect hyposynchrony, and are frequency band-specific or are distributed across the frequency spectrum. To help clarify these unresolved questions, we recorded spontaneous magnetoencephalography data and used a data-driven, whole-brain analysis of frequency-specific interregional synchrony in higher-functioning adolescents and adults, with 17 ASD and 18 control subjects matched on age, IQ, and sex, and equal for motion. Individuals with ASD showed local hypersynchrony in the theta band (4-7 Hz) in the lateral occipitotemporal cortex. Long-range hyposynchrony was seen in the alpha band (10-13 Hz), which was most prominent in neural circuitry underpinning socia...
Journal of autism and developmental disorders, 2018
There is growing evidence of a camouflaging effect among females with autism spectrum disorder (A... more There is growing evidence of a camouflaging effect among females with autism spectrum disorder (ASD), particularly among those without intellectual disability, which may affect performance on gold-standard diagnostic measures. This study utilized an age- and IQ-matched sample of school-aged youth (n = 228) diagnosed with ASD to assess sex differences on the ADOS and ADI-R, parent-reported autistic traits, and adaptive skills. Although females and males were rated similarly on gold-standard diagnostic measures overall, females with higher IQs were less likely to meet criteria on the ADI-R. Females were also found to be significantly more impaired on parent reported autistic traits and adaptive skills. Overall, the findings suggest that some autistic females may be missed by current diagnostic procedures.
Childhood-onset schizophrenia (COS) is a rare, severe form of the adult-onset disorder (AOS). Our... more Childhood-onset schizophrenia (COS) is a rare, severe form of the adult-onset disorder (AOS). Our previous resting-state fMRI study identified attenuated functional connectivity in COS compared with controls. Here, we ask whether COS and AOS patients and their siblings exhibit similar abnormalities of functional connectivity. A whole-brain, data-driven approach was used to assess resting-state functional connectivity differences in COS (patients/siblings/controls, n: 26/28/33) and AOS (n: 19/28/30). There were no significant differences in age, sex, or head motion across groups in each dataset and as designed, the COS dataset has a significantly lower age than the AOS. Both COS and AOS patients showed decreased functional connectivity relative to controls among a wide set of brain regions (P<0.05, corrected), but their siblings did not. Decreased connectivity in COS and AOS patients showed no amplitude differences and was not modulated by age-at-onset or medication doses. Cluster...
Recent findings in monkeys suggest that intrinsic periodic spiking activity in selective cortical... more Recent findings in monkeys suggest that intrinsic periodic spiking activity in selective cortical areas occurs at timescales that follow a sensory or lower order-to-higher order processing hierarchy (Murray JD, Bernacchia A, Freedman DJ, Romo R, Wallis JD, Cai X, Padoa-Schioppa C, Pasternak T, Seo H, Lee D, Wang XJ. Nat Neurosci 17: 1661–1663, 2014). It has not yet been fully explored if a similar timescale hierarchy is present in humans. Additionally, these measures in the monkey studies have not addressed findings that rhythmic activity within a brain area can occur at multiple frequencies. In this study we investigate in humans if regions may be biased toward particular frequencies of intrinsic activity and if a full cortical mapping still reveals an organization that follows this hierarchy. We examined the spectral power in multiple frequency bands (0.5–150 Hz) from task-independent data using magnetoencephalography (MEG). We compared standardized power across bands to find regi...
Head motion can be estimated at any point of fMRI image processing. Processing steps involving te... more Head motion can be estimated at any point of fMRI image processing. Processing steps involving temporal interpolation (e.g., slice time correction or outlier replacement) often precede motion estimation in the literature. From first principles it can be anticipated that temporal interpolation will alter head motion in a scan. Here we demonstrate this effect and its consequences in five large fMRI datasets. Estimated head motion was reduced by 10-50% or more following temporal interpolation, and reductions were often visible to the naked eye. Such reductions make the data seem to be of improved quality. Such reductions also degrade the sensitivity of analyses aimed at detecting motion-related artifact and can cause a dataset with artifact to falsely appear artifact-free. These reduced motion estimates will be particularly problematic for studies needing estimates of motion in time, such as studies of dynamics. Based on these findings, it is sensible to obtain motion estimates prior to any image processing (regardless of subsequent processing steps and the actual timing of motion correction procedures, which need not be changed). We also find that outlier replacement procedures change signals almost entirely during times of motion and therefore have notable similarities to motion-targeting censoring strategies (which withhold or replace signals entirely during times of motion).
The existence of abnormal connectivity patterns between resting state networks in neuropsychiatri... more The existence of abnormal connectivity patterns between resting state networks in neuropsychiatric disorders, including Autism Spectrum Disorder (ASD), has been well established. Traditional treatment methods in ASD are limited, and do not address the aberrant network structure. Using real-time fMRI neurofeedback, we directly trained 3 brain nodes in participants with ASD, in which the aberrant connectivity has been shown to correlate with symptom severity. Desired network connectivity patterns were reinforced in real-time, without participants' awareness of the training taking place. This training regimen produced large, significant long-term changes in correlations at the network level, and whole brain analysis revealed that the greatest changes were focused on the areas being trained. These changes were not found in the control group. Moreover, changes in ASD resting state connectivity following the training were correlated to changes in behavior, suggesting that neurofeedbac...
Journal of autism and developmental disorders, Jan 14, 2017
For individuals with autism spectrum disorder (ASD), long-term outcomes have been troubling, and ... more For individuals with autism spectrum disorder (ASD), long-term outcomes have been troubling, and intact IQ has not been shown to be protective. Nevertheless, relatively little research into adaptive functioning among adults with ASD has been completed to date. Therefore, both adaptive functioning and comorbid psychopathology were assessed among 52 adults with ASD without intellectual disability (ID). Adaptive functioning was found to substantially lag behind IQ, and socialization was a particular weakness. Comorbid psychopathology was significantly correlated with the size of IQ-adaptive functioning discrepancy. These findings emphasize key intervention targets of both adaptive skill and psychopathology for transition-age youth and young adults with ASD, as well as the need for ongoing monitoring of anxiety and depression symptoms during this developmental window.
The homeostatic regulation of feeding behavior requires an organism to be able to integrate infor... more The homeostatic regulation of feeding behavior requires an organism to be able to integrate information from its internal environment, including peripheral visceral signals about the body's current energy needs, with information from its external environment, such as the palatability of energy-rich food stimuli. The insula, which serves as the brain's primary sensory cortex for representing both visceral signals from the body and taste signals from the mouth and tongue, is a likely candidate region in which this integration might occur. However, to date it has been unclear whether information from these two homeostatically critical faculties is merely co-represented in the human insula, or actually integrated there. Recent functional neuroimaging evidence of a common substrate for visceral interoception and taste perception within the human dorsal mid-insula suggests a model whereby a single population of neurons may integrate viscerosensory and gustatory signals. To test th...
Journal of autism and developmental disorders, Feb 23, 2016
Although social-communication difficulties and repetitive behaviors are hallmark features of auti... more Although social-communication difficulties and repetitive behaviors are hallmark features of autism spectrum disorder (ASD) and persist across the lifespan, very few studies have compared age-related differences in these behaviors between youth with ASD and same-age typically developing (TD) peers. We examined this issue using SRS-2 (Social Responsiveness Scale-Second Edition) measures of social-communicative functioning and repetitive behaviors in a stratified cross-sectional sample of 324 youth with ASD in the absence of intellectual disability, and 438 TD youth (aged 4-29 years). An age-by-group interaction emerged indicating that TD youth exhibited age-related improvements in social-communication scores while the ASD group demonstrated age-related declines in these scores. This suggests that adolescents/adults with ASD may fall increasingly behind their same-age peers in social-communicative skills.
The anterior region of the left superior temporal gyrus/superior temporal sulcus (aSTG/STS) has b... more The anterior region of the left superior temporal gyrus/superior temporal sulcus (aSTG/STS) has been implicated in two very different cognitive functions: sentence processing and social-emotional processing. However, the vast majority of the sentence stimuli in previous reports have been of a social or social-emotional nature suggesting that sentence processing may be confounded with semantic content. To evaluate this possibility we had subjects read word lists that differed in phrase/constituent size (single words, 3-word phrases, 6-word sentences) and semantic content (social-emotional, social, and inanimate objects) while scanned in a 7T environment. This allowed us to investigate if the aSTG/STS responded to increasing constituent structure (with increased activity as a function of constituent size) with or without regard to a specific domain of concepts, i.e., social and/or social-emotional content. Activity in the left aSTG/STS was found to increase with constituent size. This...
... Britain 0028 3932 97 17,00+0,00 Automatic semantic priming of nouns and verbs in patients wit... more ... Britain 0028 3932 97 17,00+0,00 Automatic semantic priming of nouns and verbs in patients with Alzheimer's disease CAMILLE M. BUSHELL ... Neely, JH Semantic priming and retrieval from lexical memory: roles ofinhibitionless spreading acti vation and limited capacity attention ...
Journal of autism and developmental disorders, Jan 16, 2015
Although executive functioning (EF) difficulties are well documented among children and adolescen... more Although executive functioning (EF) difficulties are well documented among children and adolescents with autism spectrum disorder (ASD), little is known about real-world measures of EF among adults with ASD. Therefore, this study examined parent-reported real-world EF problems among 35 adults with ASD without intellectual disability and their correlations with adaptive functioning and co-morbid anxiety and depression symptomatology. A variable EF profile was found with prominent deficits occurring in flexibility and metacognition. Flexibility problems were associated with anxiety-related symptoms while metacognition difficulties were associated with depression symptoms and impaired adaptive functioning (though the metacognition-adaptive functioning relationship was moderated by ADHD symptoms). These persistent EF problems are predictors of broader functioning and therefore remain an important treatment target among adults with ASD.
A single exposure to an object can produce long-lasting behavioral change. Here, using event-rela... more A single exposure to an object can produce long-lasting behavioral change. Here, using event-related functional magnetic resonance imaging (fMRI), we provide evidence for long-lasting changes in cortical activity associated with perceiving and naming objects. In posterior regions, we observed an immediate (30-second) and long-lasting (3-day) decrease in neural activity after brief (200-ms) exposure to nameable and nonsense objects. In addition, slower-developing decreases in left inferior frontal activity were observed concurrently with increases in left insula activity, only for nameable objects. These time-dependent cortical changes may reflect two distinct learning mechanisms: the formation of sparser, yet more object-form-specific, representations in posterior regions, and experience-induced reorganization of the brain circuitry underlying lexical retrieval in anterior regions.
One of the most robust and oft-replicated findings in cognitive neuroscience is that several spat... more One of the most robust and oft-replicated findings in cognitive neuroscience is that several spatially distinct, functionally dissociable ventral occipitotemporal cortex (VOTC) regions respond preferentially to different categories of concrete entities. However, the determinants of this category-related organization remain to be fully determined. One recent proposal is that privileged connectivity of these VOTC regions with other regions that store and/or process category-relevant properties may be a major contributing factor. To test this hypothesis, we used a multicategory functional magnetic resonance imaging (MRI) localizer to individually define category-related brain regions of interest (ROIs) in a large group of subjects (n = 33). We then used these ROIs in resting-state functional connectivity MRI analyses to explore spontaneous functional connectivity among these regions. We demonstrate that during rest, distinct category-preferential VOTC regions show differentially strong...
To investigate the functional neuroanatomy associated with retrieving semantic and episodic memor... more To investigate the functional neuroanatomy associated with retrieving semantic and episodic memories\ we measured changes in regional cerebral blood~ow "rCBF# with positron emission tomography "PET# while subjects generated single word responses to achromatic line drawings of objects[ During separate scans\ subjects either named each object\ retrieved a commonly associated color of each object "semantic condition#\ or recalled a previously studied uncommon color of each object "episodic condition#[ Subjects were also scanned while staring at visual noise patterns to provide a low level perceptual baseline[ Relative to the low level baseline\ all three conditions revealed bilateral activations of posterior regions of the temporal lobes\ cerebellum\ and left lateralized activations in frontal regions[ Retrieving semantic information\ as compared to object naming\ activated left inferior temporal\ left superior parietal\ and left frontal cortices[ In addition\ small regions of right frontal cortex were activated[ Retrieving episodic information\ as compared to object naming\ activated bilateral medial parietal cortex\ bilateral retrosplenial cortex\ right frontal cortex\ thalamus\ and cerebellum[ Direct comparison of the semantic and episodic conditions revealed bilateral activation in temporal and frontal lobes in the semantic task "left greater than right#\ and activation in medial parietal cortex\ retrosplenial cortex\ thalamus\ and cerebellum "but not right frontal regions# in the episodic task[ These results support the assertion that distinct neural structures mediate semantic and episodic memory retrieval[ However\ they also raise questions regarding the speci_c roles of left temporal and right frontal cortices during episodic memory retrieval\ in particular[ Þ 0887 Elsevier Science Ltd[ All rights reserved[
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