Environmental Enrichment Results in Both Brain Connectivity Efficiency and Selective Improvement in Different Behavioral Tasks.

Exposure to environmental enrichment (EE) has been a useful model for studying the effects of experience on brain plasticity, but to date, few is known about the impact of this condition on the brain functional networks that probably underlies the multiple behavioral improvements. Hence, we assessed the effect of an EE protocol in adult Wistar rats on the performance in several behavioral tasks testing different domains (Open field (OP): locomotor activity; Elevated-zero maze (EZM): anxiety-related behaviors; 5-choice serial reaction time task (5-CSRTT): attentional processes; 4-arm radial water maze (4-RAWM): spatial memory) in order to check its effectiveness in a wide range of functions. After this, we analyzed the functional brain connectivity underlying each experimental condition through cytochrome C oxidase (COx) histochemistry. Our EE protocol reduced both locomotor activity in the OP and anxiety-related behaviors in the EZM. On the other hand, enriched rats showed more accuracy in the 4-RAWM, whereas 5-CSRTT performance was not significantly ameliorated by EE condition. In relation to COx functional connectivity, we found that EE reduced the number of strong positive correlations both in basal and training conditions, suggesting a modulating effect on specific brain connections. Our results suggest that EE seems to have a selective effect on specific brain regions, such as prefrontal cortex and hippocampus, leading to a more efficient brain connectivity.

Familial IgA nephropathy associated with bilateral sensorineural deafness.

Alport's syndrome is the most frequent disorder with familial nephritis and deafness, but other types of nephropathy have been occasionally associated with hereditary hearing loss. The familial occurrence of IgA nephropathy has been well documented. We report a family with hereditary, bilateral, sensorineural deafness spanning four generations. Three of five members with deafness had microscopic hematuria. Renal histology of the two deaf members undergoing biopsy showed mesangial glomerulonephritis with mesangial IgA deposits, without ultrastructural abnormalities of the glomerular basement membranes. Familial nephritis with deafness should not be equated with the diagnosis of Alport's syndrome.