Publications by authors named "Daniel P Kennedy"

Background: Motor challenges are highly prevalent within autism, and increased postural sway has been consistently demonstrated in autistic youth. However, the extent to which sway anomalies extend into adulthood remains understudied. This study aimed to investigate whether increased postural sway is altered in autistic adults compared to neurotypical controls using established sway metrics including sway area and path, as well as rambling-trembling decomposition—an approach that differentiates the postural sway signal into central and peripheral nervous system components.

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Background: Difficulty in social inferences is a core feature in autism spectrum disorders (ASD). On the behavioral level, it remains unclear whether reasoning about others' mental states (Theory of Mind, ToM) and empathic responses to others' physical states may be similarly or differentially affected in autism. On the neural level, these inferences typically engage distinct brain networks (ToM versus Pain networks), but their functional specialization remains not well understood in autism.

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Recent studies have highlighted the intricate relationship between cerebrospinal fluid (CSF) dynamics and global brain activity, suggesting a role in neurovascular coupling and brain waste clearance. The lateral ventricles are believed to play a key role in linking global BOLD (gBOLD) signals to CSF inflow (CSF) to the fourth ventricle. In this study, we developed a method to reliably quantify lateral ventricle volume (LVV) in fMRI data.

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There has been a recent surge of naturalistic methodology to assess complex topics in psychology and neuroscience. Such methods are lauded for their increased ecological validity, aiming to bridge a gap between highly controlled experimental design and purely observational studies. However, these measures present challenges in establishing construct validity.

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How does the human brain respond to novelty? Here, we address this question using fMRI data wherein human participants watch the same movie scene four times. On the first viewing, this movie scene is novel, and on later viewings it is not. We find that brain activity is lower-dimensional in response to novelty.

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Atypical gaze patterns are a promising biomarker of autism spectrum disorder. To measure gaze accurately, however, it typically requires highly controlled studies in the laboratory using specialized equipment that is often expensive, thereby limiting the scalability of these approaches. Here we test whether a recently developed smartphone-based gaze estimation method could overcome such limitations and take advantage of the ubiquity of smartphones.

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Recent studies have shown that functional connectivity can be decomposed into its exact frame-wise contributions, revealing short-lived, infrequent, and high-amplitude time points referred to as "events." Events contribute disproportionately to the time-averaged connectivity pattern, improve identifiability and brain-behavior associations, and differences in their expression have been linked to endogenous hormonal fluctuations and autism. Here, we explore the characteristics of events while subjects watch movies.

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Nearly half the published research in psychology is conducted with online samples, but the preponderance of these studies rely primarily on self-report measures. The current study validated data quality from an online sample on a novel, dynamic task by comparing performance between an in-lab and online sample on two dynamic measures of theory of mind-the ability to infer others' mental states. Theory of mind is a cognitively complex construct that has been widely studied across multiple domains of psychology.

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Objectives: Theory of mind-the ability to infer others' mental states-declines over the life span, potentially due to cognitive decline. However, it is unclear whether deficits emerge because older adults use the same strategies as young adults, albeit less effectively, or use different or no strategies. The current study compared the similarity of older adults' theory of mind errors to young adults' and a random model.

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Background: Across behavioral studies, autistic individuals show greater variability than typically developing individuals. However, it remains unknown to what extent this variability arises from heterogeneity across individuals, or from unreliability within individuals. Here, we focus on eye tracking, which provides rich dependent measures that have been used extensively in studies of autism.

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The interaction between brain regions changes over time, which can be characterized using time-varying functional connectivity (tvFC). The common approach to estimate tvFC uses sliding windows and offers limited temporal resolution. An alternative method is to use the recently proposed edge-centric approach, which enables the tracking of moment-to-moment changes in co-fluctuation patterns between pairs of brain regions.

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Children's ability to share attention with another person (i.e., achieve joint attention) is critical for learning about their environments in general and supporting language and object word learning in particular.

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Naturalistic imaging paradigms, in which participants view complex videos in the scanner, are increasingly used in human cognitive neuroscience. Videos evoke temporally synchronized brain responses that are similar across subjects as well as within subjects, but the reproducibility of these brain responses across different data acquisition sites has not yet been quantified. Here, we characterize the consistency of brain responses across independent samples of participants viewing the same videos in functional magnetic resonance imaging (fMRI) scanners at different sites (Indiana University and Caltech).

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Visual search guides goal-directed action in humans and many other species, and it has been studied extensively in the past. Yet, no study has investigated the relative contributions of genes and environments to individual differences in visual search performance, or to which extent etiologies are shared with broader cognitive phenotypes. To address this gap, we studied visual search and general intelligence in 156 monozygotic (MZ) and 158 same-sex dizygotic (DZ) twin pairs.

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CTEA (N,N-bis[2-(carboxylmethyl)thioethyl]amine) is a mixed donor ligand that has been incorporated into multiple fluorescent sensors such as NiSensor-1 that was reported to be selective for Ni . Other metal ions such as Zn do not produce an emission response in aqueous solution. To investigate the coordination chemistry and selectivity of this receptor, we prepared NiCast, a photocage containing the CTEA receptor.

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Article Synopsis
  • The study investigates how the characteristics of older adults' social networks affect their memory and social cognitive functions, particularly their ability to understand others' thoughts and feelings.
  • It involved 120 older adults who participated in interviews and completed tests measuring their memory and social cognitive abilities, including emotion recognition and theory of mind.
  • Findings indicate that better memory is linked to larger but less dense social networks, while improved theory of mind is associated with having diverse social relationships and at least one acquaintance in their network.
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Multimodal exploration of objects during toy play is important for a child's development and is suggested to be abnormal in children with autism spectrum disorder (ASD) due to either atypical attention or atypical action. However, little is known about how children with ASD coordinate their visual attention and manual actions during toy play. The current study aims to understand if and in what ways children with ASD generate exploratory behaviors to toys in natural, unconstrained contexts by utilizing head-mounted eye tracking to quantify moment-by-moment attention.

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Resting-state functional connectivity is used throughout neuroscience to study brain organization and to generate biomarkers of development, disease, and cognition. The processes that give rise to correlated activity are, however, poorly understood. Here we decompose resting-state functional connectivity using a temporal unwrapping procedure to assess the contributions of moment-to-moment activity cofluctuations to the overall connectivity pattern.

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This study investigated the association between the ability to maintain prolonged (2-minute) fixation on a visual target and ADHD traits in a sample consisting of 120 monozygotic and 120 dizygotic twin pairs, aged 9 to 14 years. More intrusive saccades during the task was associated with higher level of parent-reported ADHD traits. Both intrusive saccades and ADHD symptoms had high heritability estimates, and there was a moderate genetic correlation between number of intrusive saccades and ADHD.

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Despite enthusiasm about the potential for using fMRI-based functional connectomes in the development of biomarkers for autism spectrum disorder (ASD), the literature is full of negative findings-failures to distinguish ASD functional connectomes from those of typically developing controls (TD)-and positive findings that are inconsistent across studies. Here, we report on a new study designed to either better differentiate ASD from TD functional connectomes-or, alternatively, to refine our understanding of the factors underlying the current state of affairs. We scanned individuals with ASD and controls both at rest and while watching videos with social content.

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Brain networks are flexible and reconfigure over time to support ongoing cognitive processes. However, tracking statistically meaningful reconfigurations across time has proven difficult. This has to do largely with issues related to sampling variability, making instantaneous estimation of network organization difficult, along with increased reliance on task-free (cognitively unconstrained) experimental paradigms, limiting the ability to interpret the origin of changes in network structure over time.

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Background: Top-down volitional command of eye movements may serve as a candidate endophenotype of ADHD, an important function underlying goal-directed action in everyday life. In this twin study, we examined the relation between performance on a response inhibition eye-tracking paradigm and parent-rated ADHD traits in a population-based twin sample. We hypothesized that altered eye movement control is associated with the severity of ADHD traits and that this association is attributable to genetic factors.

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A rapidly growing number of studies on autism spectrum disorder (ASD) have used resting-state fMRI to identify alterations of functional connectivity, with the hope of identifying clinical biomarkers or underlying neural mechanisms. However, results have been largely inconsistent across studies, and there remains a pressing need to determine the primary factors influencing replicability. Here, we used resting-state fMRI data from the Autism Brain Imaging Data Exchange to investigate two potential factors: denoising strategy and data site (which differ in terms of sample, data acquisition, etc.

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Adolescents with autism often experience pronounced difficulties with social communication, and novel interventions designed to improve core abilities are greatly needed. This study examines if providing immediate video feedback, an extension of video self-modeling, can aid adolescents with autism to self-identify strengths and irregularities from their social interactions. Using multiple baseline design across four participants, individuals engaged in naturalistic conversations wearing video recording glasses.

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