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Matuskey, D.

Publications and source records attributed to Matuskey, D..

4 recordsLinked to original sources

Synaptic density imaging associates with performance but not self-report in autism

Autism is a common neurodevelopmental condition with considerable between-person variability and unknown biological etiology. Diagnosis of autism in adults relies on measurement of performance (e.g., clinician rating of social behavior, standardized assessment of cognition) and self-report of autism features. Our prior work revealed a strong relationship between clinician ratings of social function in autism and in vivo measures of synaptic density as measured by [11C]UCB-J PET (Matuskey et al., 2025). However, it is not understood how the measured aspects of the autism phenotype index underlying biology. Here, in a sample of 12 autistic adults, we address this question by relating synaptic density imaging to a range of performance measures, such as cognition and face recognition, in contrast to self-report measures. Our results identify a dissociation between these measurement types in that synaptic density correlates strongly with measures of performance but shows virtually no relationship with self-report. These findings suggest that, while self-report and performance measures share variance in characterizing phenotypes in autism, they diverge when mapping onto the underlying biology. Results suggest that higher synaptic density may index a general mechanism that facilitates social and cognitive performance across a range of tasks. These data also indicate that performance and self-report measures are not interchangeable in capturing brain-behavior correspondences in autism, a finding that can guide measure selection in future biomarker studies and clinical research.

neuroscience↗

Optimized reference region and the effect on test-retest reliability and detection of Parkinson's disease with UCB-J.

[11C]UCB-J is a radioligand targeting synaptic vesicle glycoprotein 2A, used to image synaptic density. For quantification, a small-volume centrum semiovale area was previously optimized as a [11C]UCB-J reference region (CS2mL); however, its high variability resulted in reduced reliability. Herin, we evaluated an alternative reference region method to assess longitudinal test-retest reliability and detection of Parkinsons disease (PD). For estimating distribution volume ratio (DVR), CS2mL and eleven white matter (WM) reference regions (range: 0.5-200 mL) were generated using the Freesurfer WM map. Same-day and longitudinal test-retest variability (TRV) were assessed (24 healthy subjects (HS); n=10 same-day and n=20 longitudinal HRRT scans, range: 7-1028 days). Each reference region was used to evaluate the substantia nigra (SN) and caudate DVRs in HS (n=25) and PD (n=20). The 10mL WM reference region yielded [11C]UCB-J DVR measurements with reduced variability in TRV (same-day: 10mL: 1.2{+/-}5.7%, same-day: CS2mL: -0.9{+/-}9.2% longitudinal: 10mL: 1.5{+/-}7.0%, CS2mL: 1.6{+/-}11.9%,) while maintaining <10% volume of distribution difference, compared to CS2mL. Further, a significant difference between PD and HS groups in SN and caudate DVRs was found using 10mL, with greater effect size (Cohens d 0.61 for SN and 0.66 for caudate) compared to CS2mL (0.38 for SN and 0.43 for caudate).

neuroscience↗

Effects of age, BMI and sex on the glial cell marker TSPO - a multicentre PBR28 HRRT PET study

PurposeTo investigate the effects of ageing, sex and body mass index (BMI) on translocator protein (TSPO) availability in healthy subjects using positron emission tomography (PET) and the radioligand [11C]PBR28. Methods[11C]PBR28 data from 140 healthy volunteers (72 males and 68 females; n=78 with HAB and n=62 MAB genotype; age range 19-80 years; BMI range 17.6 - 36.9) were acquired with High Resolution Research Tomograph at three centres: Karolinska Institutet (n=53), Turku PET centre (n=62) and Yale University PET Center (n=25). The total volume of distribution (VT) was estimated in global grey matter, frontal, temporal, occipital and parietal cortices, hippocampus and thalamus using multilinear analysis 1. The effects of age, BMI and sex on TSPO availability were investigated using linear mixed effects model, with TSPO genotype and PET centre specified as random intercepts. ResultsThere were significant positive correlations between age and VT in the frontal and temporal cortex. BMI showed a significant negative correlation with VT in all regions. Additionally, significant differences between males and females were observed in all regions, with females showing higher VT. A subgroup analysis revealed a positive correlation between VT and age in all regions in male subjects, whereas age showed no effect on TSPO levels in female subjects. ConclusionThese findings provide evidence that individual biological properties may contribute significantly to the high variation shown in TSPO binding estimates, and suggest that age, BMI and sex can be confounding factors in clinical studies.

immunology↗

Reliability of the correlative triad among aging, dopamine D2-like receptor availability, and cognition

The evidence that dopamine function mediates the association between aging and cognition is one of the most cited findings in the cognitive neuroscience of aging. However, few and relatively small studies have directly examined these associations. Here we examined correlations among adult age, dopamine D2-like receptor (D2R) availability, and cognition in two cross-sectional studies of healthy human adults. Participants completed a short cognitive test battery and, on a separate day, a PET scan with either the high-affinity D2R tracer [18F]Fallypride (Study 1) or [11C]FLB457 (Study 2). Digit span, a measure of short-term memory maintenance and working memory, was the only cognitive test for which dopamine D2R availability partially mediated the age effect on cognition. In Study 1, age was negatively correlated with digit span. Striatal D2R availability was positively correlated with digit span controlling for age. The age effect on digit span was smaller when controlling for striatal D2R availability. Although other cognitive measures used here have individually been associated with age and D2R availability in prior studies, we found no consistent evidence for significant associations between low D2R availability and low cognitive performance on these measures. These results at best only partially supported the correlative triad of age, dopamine D2R availability, and cognition. While a wealth of other research in human and non-human animals demonstrates that dopamine makes critical contributions to cognition, the present studies suggest caution in interpreting PET findings as evidence that dopamine D2R loss is a primary cause of broad age-related declines in fluid cognition.

neuroscience↗