Environmental enrichment (EE) increases dentate gyrus (DG) neurogenesis and brain-derived neurotrophic factor (BDNF) levels. However, running is considered an element of EE. To dissociate effects of physical activity and enrichment on hippocampal neurogenesis and BDNF levels, young female C57Bl/6 mice were housed under control, running, enrichment, or enrichment plus running conditions, and injected with bromodeoxyuridine. Cell genesis was assessed after 12 d and differentiation was analyzed 1 mo later. In addition, locomotor activity in the open field and hippocampal mature BDNF peptide levels were measured. Open-field adaptation was improved in all groups, compared to controls, but more so with running. New cell proliferation, survival, neuron number, and neurotrophin levels were enhanced only when running was accessible. We conclude that exercise is the critical factor mediating increased BDNF levels and adult hippocampal neurogenesis.[Supplemental material is available for this article.]Exposure to environmental enrichment (EE) has positive effects on brain function, including increased numbers of dendritic branches and spines, enlargement of synapses, and improved cognition (Bennett et al. 1964;Rosenzweig and Bennett 1996). More recently, it was discovered that EE enhances the survival of newly born neurons in the dentate gyrus (DG) of the hippocampus (Kempermann et al. 1997) and increases brain-derived neurotrophic factor (BDNF) levels (Falkenberg et al. 1992;Rossi et al. 2006;Sun et al. 2010). EE has many aspects, including increased opportunity for learning, socialization, and physical activity. Among these, exercise was found to enhance neurogenesis (van Praag et al. 1999). Subsequently, physical activity and enrichment have been regarded as equivalent neurogenic stimuli, albeit with different underlying mechanisms. Exercise is considered to mainly enhance cell proliferation, whereas enrichment is deemed to increase new cell survival (Olson et al. 2006;Kempermann et al. 2010). However, in many studies the enriched environment includes physical activity (Kempermann et al. 1997(Kempermann et al. , 1998van Praag et al. 1999;Rossi et al. 2006;Schloesser et al. 2010;Sun et al. 2010), making it difficult to assess the unique contributions of EE and exercise to adult neurogenesis, neurotrophin levels, and behavior.The current study aims to directly differentiate between the effects of enriched environment only (EEO), physical activity (RUN), and the combination of enrichment and running (EER). Here we show that running is the critical factor in stimulating adult hippocampal neurogenesis and enhancing mature BDNF peptide levels. Moreover, enrichment in the absence of running does not increase adult hippocampal neurogenesis or BDNF levels in the hippocampus. Open-field adaptation was improved in all groups as compared to controls, but more so in the groups that included running. These findings suggest that enrichment and exercise are distinct functional interventions.Forty female C57B1/6 mice (5 wk old) were div...

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SUMMARY -The corpus callosal splenium is an uncommon location for Wallerian degeneration (WD), which may be mistaken for new pathology on magnetic resonance imaging (MRI). We describe the case of a 69-year-old woman with a left posterior cerebral artery infarct in whom progressive

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Hypersomnolence is common in children and adolescents and its etiology is multifactorial. Developmental changes in melatonin release and slower accumulation of sleep pressure lead to a preference for later sleep times, which conflicts with early school start times leading to increased daytime sleepiness. Although the most common cause of daytime sleepiness in children and adolescents is insufficient sleep, central disorders of hypersomnolence can also manifest in these age groups. Excessive sleepiness could also result from other disorders such as sleep apnea, psychiatric illnesses, and medication use. Hypersomnolence should be evaluated by careful history taking, and when necessary additional tests including actigraphy, polysomnography, and multiple sleep latency test may need to be performed. In this review, we discuss the prevalence of hypersomnolence in children and adolescents, common etiological factors, and assessment of excessive sleepiness. We also discuss management strategies for hypersomnolence. [ Psychiatr Ann. 2019;49(12):529–534.]

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