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Wilkinson, M. K.

Publications and source records attributed to Wilkinson, M. K..

3 recordsLinked to original sources

Increased heterogeneity and task-related reconfiguration of functional connectivity within a lexicosemantic network in autism

Autism spectrum disorder (ASD) is highly heterogeneous in etiology and clinical presentation. Findings on intrinsic functional connectivity (FC) or task-induced FC in ASD have been inconsistent including both over- and underconnectivity and diverse regional patterns. As FC patterns change across different cognitive demands, a novel and more comprehensive approach to network architecture in ASD is to examine the change in FC patterns between rest and task states, referred to as reconfiguration. This approach is suitable for investigating inefficient network connectivity that may underlie impaired behavioral functioning in clinical disorders. We used functional magnetic resonance imaging (fMRI) to examine FC reconfiguration during lexical processing, which is often affected in ASD, with additional focus on interindividual variability. Thirty adolescents with ASD and a matched group of 23 typically developing (TD) participants completed a lexicosemantic decision task during fMRI, using multiecho-multiband pulse sequences with advanced BOLD signal sensitivity and artifact removal. Regions of interest (ROIs) were selected based on task-related activation across both groups, and FC and reconfiguration were compared between groups. The ASD group showed increased interindividual variability and overall greater reconfiguration than the TD group. An ASD subgroup with typical performance accuracy (at the level of TD participants) showed reduced similarity and typicality of FC during the task. In this ASD subgroup, greater FC reconfiguration was associated with increased language skills. Findings suggest that intrinsic functional networks in ASD may be inefficiently organized for lexicosemantic decisions and may require greater reconfiguration during task processing, with high performance levels in some individuals being achieved through idiosyncratic mechanisms. HighlightsFC reconfiguration is a comprehensive approach to examining network architecture Functional networks are inefficiently organized for lexicosemantic decisions in ASD ASD may require greater reconfiguration during task processing Some ASD individuals achieve high performance through idiosyncratic mechanisms

neuroscience↗

Digging behavior discrimination test to probe burrowing and exploratory digging in male and female mice

Digging behavior is often used to test motor function and repetitive behaviors in mice. Different digging paradigms have been developed for behaviors related to anxiety and compulsion in mouse lines generated to recapitulate genetic mutations leading to psychiatric and neurological disorders. However, the interpretation of these tests has been confounded by the difficulty of determining the motivation behind digging in mice. Digging is a naturalistic mouse behavior, that can be focused toward different goals, i.e. foraging for food, burrowing for shelter, burying objects, or even for recreation as has been shown for dogs, ferrets, and human children. However, the interpretation of results from current testing protocols assumes the motivation behind the behavior often concluding that increased digging is a repetitive or compulsive behavior. We asked whether providing a choice between different types of digging activities would increase sensitivity to assess digging motivation. Here, we present a test to distinguish between burrowing and exploratory digging in mice. We found that mice prefer burrowing when the option is available. When food restriction was used to promote a switch from burrowing to exploration, males readily switched from burrowing to digging outside, while females did not. In addition, when we tested a model of intellectual disability and autism spectrum disorder that had shown inconsistent results in the marble burying test, the Cc2d1a conditional knock-out mouse, we found greatly reduced burrowing only in males. Our findings indicate that digging is a nuanced motivated behavior and suggest that male and female rodents may perform it differently. Significance StatementDigging behavior is commonly assessed in mice to study features of neurodevelopmental, psychiatric and neurological disorder. However, existing digging assays fail to discriminate between types of digging complicating data interpretation. Here we present a modified digging behavior discrimination task that can produce sensitive results in 30 minutes with easy to gather measures, making it accessible to wide variety of labs and experimental paradigms.

neuroscience↗

Male-specific CREB signaling in the hippocampus controls spatial memory deficits in a mouse model of autism and intellectual disability

BackgroundThe prevalence of neurodevelopmental disorders is biased towards males with male: female ratios of 2:1 in intellectual disability (ID) and 4:1 in autism spectrum disorder (ASD). However, the molecular mechanisms of such bias remain unknown. While characterizing a mouse model for loss of the signaling scaffold coiled-coil and C2 domain containing 1A (CC2D1A), which is mutated in ID and ASD, we identified biochemical and behavioral differences between males and females, and explored whether CC2D1A controls male-specific intracellular signaling.\n\nMethodsCC2D1A is known to regulate phosphodiesterase 4D (PDE4D). We tested for activation PDE4D and downstream signaling molecules such as CREB in the hippocampus of Cc2d1a-deficient mice. We then performed behavioral studies in females to analyze learning and memory, social interactions, anxiety and hyperactivity. Finally, we targeted PDE4D activation with a PDE4D inhibitor to define how changes in PDE4D and CREB activity affect behavior in males and females.\n\nResultsWe found that in Cc2d1a-deficient males PDE4D is hyperactive leading to a reduction in CREB signaling, but this molecular deficit is not present in females. Cc2d1a-deficient females only show impairment in novel object recognition, and no other cognitive and social deficits that have been found in males. Restoring PDE4D activity using an inhibitor rescues male-specific cognitive deficits, but has no effect on females.\n\nConclusionsOur findings show that CC2D1A regulates intracellular signaling in a male-specific manner in the hippocampus leading to male-specific behavioral deficits. We propose that male-specific signaling mechanisms are involved in establishing sex bias in neurodevelopmental disorders.

neuroscience↗