Age-related differences in task-induced brain activation is not task specific: Multivariate pattern generalization between metacognition, cognition and perception.

Adolescence is associated with widespread maturation of brain structures and functional connectivity profiles that shift from local to more distributed and better integrated networks, which are active during a variety of cognitive tasks. Nevertheless, the approach to examine task-induced developmental brain changes is function-specific, leaving the question open whether functional maturation is specific to the particular cognitive demands of the task used, or generalizes across different tasks. In the present study we examine the hypothesis that functional brain maturation is driven by global changes in how the brain handles cognitive demands. Multivariate pattern classification analysis (MVPA) was used to examine whether age discriminative task-induced activation patterns generalize across a wide range of information processing levels. 25 young (13-years old) and 22 old (17-years old) adolescents performed three conceptually different tasks of metacognition, cognition and visual processing. MVPA applied within each task indicated that task-induced brain activation is consistent and reliably different between ages 13 and 17. These age-discriminative activation patterns proved to be common across the different tasks used, despite the differences in cognitive demands and brain structures engaged by each of the three tasks. MVP classifiers trained to detect age-discriminative patterns in brain activation during one task were significantly able to decode age from brain activation maps during execution of other tasks with accuracies between 63 and 75%. The results emphasize that age-specific characteristics of task-induced brain activation have to be understood at the level of brain-wide networks that show maturational changes in their organization and processing efficacy during adolescence.

Purkinje-cell-specific DNA repair-deficient mice reveal that dietary restriction protects neurons by cell-intrinsic preservation of genomic health.

Dietary restriction (DR) is a universal anti-aging intervention, which reduces age-related nervous system pathologies and neurological decline. The degree to which the neuroprotective effect of DR operates by attenuating cell intrinsic degradative processes rather than influencing non-cell autonomous factors such as glial and vascular health or systemic inflammatory status is incompletely understood. Following up on our finding that DR has a remarkably large beneficial effect on nervous system pathology in whole-body DNA repair-deficient progeroid mice, we show here that DR also exerts strong neuroprotection in mouse models in which a single neuronal cell type, i.e., cerebellar Purkinje cells, experience genotoxic stress and consequent premature aging-like dysfunction. Purkinje cell specific hypomorphic and knock-out ERCC1 mice on DR retained 40 and 25% more neurons, respectively, with equal protection against P53 activation, and alike results from whole-body ERCC1-deficient mice. Our findings show that DR strongly reduces Purkinje cell death in our Purkinje cell-specific accelerated aging mouse model, indicating that DR protects Purkinje cells from intrinsic DNA-damage-driven neurodegeneration.