Publications by authors named "D Garrett"

The cognitive neuroscience of human aging seeks to identify neural mechanisms behind the commonalities and individual differences in age-related behavioral changes. This goal has been pursued predominantly through structural or "task-free" resting-state functional neuroimaging. The former has elucidated the material foundations of behavioral decline, and the latter has provided key insight into how functional brain networks change with age.

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Article Synopsis
  • Recent studies showed only weak connections between age, dopamine receptor availability, and cognitive decline, suggesting more research is needed.
  • Longitudinal data over five years found that older adults who experienced declines in D2/3 dopamine receptors had worse working memory performance over time.
  • Specifically, the decline in dopamine receptor availability was significant in key brain regions linked to working memory, supporting the idea that dopamine changes contribute to cognitive aging.
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During memory formation, the hippocampus is presumed to represent the content of stimuli, but how it does so is unknown. Using computational modelling and human single-neuron recordings, we show that the more precisely hippocampal spiking variability tracks the composite features of each individual stimulus, the better those stimuli are later remembered. We propose that moment-to-moment spiking variability may provide a new window into how the hippocampus constructs memories from the building blocks of our sensory world.

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The ability to prioritize among input features according to relevance enables adaptive behaviors across the human lifespan. However, relevance often remains ambiguous, and such uncertainty increases demands for dynamic control. While both cognitive stability and flexibility decline during healthy ageing, it is unknown whether aging alters how uncertainty impacts perception and decision-making, and if so, via which neural mechanisms.

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Background: There is a shortage of rapid, accurate, and low-cost assays for diagnosing enteric fever. The dual-path platform for typhoid (DPPT) assay had high accuracy in retrospective studies with banked plasma samples. We aimed to evaluate the diagnostic accuracy of the DPPT assay in a prospective study using fingerstick capillary blood.

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