The settler colonial roots and neoliberal afterlife of Problem Behavior Theory.

Problem Behavior Theory (PBT) is an influential psychosocial theory that has shaped-and continues to shape-much research on adolescent development in the United States and abroad. It is the product of over a half-century of research conducted by psychologists-cum-behavioral scientists Lee and Richard Jessor. This article engages two striking features of the history of PBT. First, it tracks how, and to what effect, a theory elaborated to explain the so-called "deviant behavior" of a group of Native Americans was extended to explain the "problem behavior" of white, middle-class, settler youth, before coming to circulate as a universal theory of adolescent behavior. Second, it explores how a theory that was meant to explain individual behaviors by connecting them to their larger social contexts came to be embraced by researchers who have been criticized for doing precisely the opposite. To do so, this article draws from Indigenous and Settler Colonial Studies scholarship and sheds light on how the logics of settler colonialism and neoliberalism have participated in the coproduction of PBT and its reception.

Neurofilament light polypeptide gene N98S mutation in mice leads to neurofilament network abnormalities and a Charcot-Marie-Tooth Type 2E phenotype.

Charcot-Marie-Tooth disease (CMT) is the most commonly inherited neurological disorder with a prevalence of 1 in 2500 people worldwide. Patients suffer from degeneration of the peripheral nerves that control sensory information of the foot/leg and hand/arm. Multiple mutations in the neurofilament light polypeptide gene, NEFL, cause CMT2E. Previous studies in transfected cells showed that expression of disease-associated neurofilament light chain variants results in abnormal intermediate filament networks associated with defects in axonal transport. We have now generated knock-in mice with two different point mutations in Nefl: P8R that has been reported in multiple families with variable age of onset and N98S that has been described as an early-onset, sporadic mutation in multiple individuals. Nefl(P8R/+) and Nefl(P8R/P8R) mice were indistinguishable from Nefl(+/+) in terms of behavioral phenotype. In contrast, Nefl(N98S/+) mice had a noticeable tremor, and most animals showed a hindlimb clasping phenotype. Immunohistochemical analysis revealed multiple inclusions in the cell bodies and proximal axons of spinal cord neurons, disorganized processes in the cerebellum and abnormal processes in the cerebral cortex and pons. Abnormal processes were observed as early as post-natal day 7. Electron microscopic analysis of sciatic nerves showed a reduction in the number of neurofilaments, an increase in the number of microtubules and a decrease in the axonal diameters. The Nefl(N98S/+) mice provide an excellent model to study the pathogenesis of CMT2E and should prove useful for testing potential therapies.