Much evidence shows that physical exercise (PE) is a strong gene modulator that induces structural and functional changes in the brain, determining enormous benefit on both cognitive functioning and wellbeing. PE is also a protective factor for neurodegeneration. However, it is unclear if such protection is granted through modifications to the biological mechanisms underlying neurodegeneration or through better compensation against attacks. This concise review addresses the biological and psychological positive effects of PE describing the results obtained on brain plasticity and epigenetic mechanisms in animal and human studies, in order to clarify how to maximize the positive effects of PE while avoiding negative consequences, as in the case of exercise addiction.

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As major components of neuronal membranes, omega-3 polyunsaturated acids (n-3 PUFA) exhibit a wide range of regulatory functions, modulating from synaptic plasticity to neuroinflammation, from oxidative stress to neuroprotection. Recent human and animal studies indicated the n-3 PUFA neuroprotective properties in aging, with a clear negative correlation between n-3 PUFA levels and hippocampal deficits. The present multidimensional study was aimed at associating cognition, hippocampal neurogenesis, volume, neurodegeneration and metabolic correlates to verify n-3 PUFA neuroprotective effects in aging. To this aim 19 month-old mice were given n-3 PUFA mixture, or olive oil or no dietary supplement for 8 weeks during which hippocampal-dependent mnesic functions were tested. At the end of behavioral testing morphological and metabolic correlates were analyzed. n-3 PUFA supplemented aged mice exhibited better object recognition memory, spatial and localizatory memory, and aversive response retention, without modifications in anxiety levels in comparison to controls. These improved hippocampal cognitive functions occurred in the context of an enhanced cellular plasticity and a reduced neurodegeneration. In fact, n-3 PUFA supplementation increased hippocampal neurogenesis and dendritic arborization of newborn neurons, volume, neuronal density and microglial cell number, while it decreased apoptosis, astrocytosis and lipofuscin accumulation in the hippocampus. The increased levels of some metabolic correlates (blood Acetyl-L-Carnitine and brain n-3 PUFA concentrations) found in n-3 PUFA supplemented mice also pointed toward an effective neuroprotection. On the basis of the present results n-3 PUFA supplementation appears to be a useful tool in health promotion and cognitive decline prevention during aging.

Based on our synthesis of the existing literature, we conclude that individuals with ASDs can learn implicitly, supporting the hypothesis that implicit learning deficits do not represent a core feature in ASDs.

Environmental enrichment (EE) is a widely used paradigm for investigating the influence of complex stimulations on brain and behavior. Here we examined whether pre-reproductive exposure to EE of female rats may influence their maternal care and offspring cognitive performances. To this aim, from weaning to breeding age enriched females (EF) were reared in enriched environments. Females reared in standard conditions were used as controls. At 2.5 months of age all females were mated and reared in standard conditions with their offspring. Maternal care behaviors and nesting activity were assessed in lactating dams. Their male pups were also behaviorally evaluated at different post-natal days (pnd). Brain BDNF, reelin and adult hippocampal neurogenesis levels were measured as biochemical correlates of neuroplasticity. EF showed more complex maternal care than controls due to their higher levels of licking, crouching and nest building activities. Moreover, their offspring showed higher discriminative (maternal odor preference T-maze, pnd 10) and spatial (Morris Water Maze, pnd 45; Open Field with objects, pnd 55) performances, with no differences in social abilities (Sociability test, pnd 35), in comparison to controls. BDNF levels were increased in EF frontal cortex at pups' weaning and in their offspring hippocampus at pnd 21 and 55. No differences in offspring reelin and adult hippocampal neurogenesis levels were found. In conclusion, our study indicates that pre-reproductive maternal enrichment positively influences female rats' maternal care and cognitive development of their offspring, demonstrating thus a transgenerational transmission of EE benefits linked to enhanced BDNF-induced neuroplasticity.

The molecular mechanism of environmental enrichment (EE) on brain function and anatomy has been partially attributed to the up-regulation of proteins involved in neuronal survival and activity-dependent plasticity, such as the neurotrophins nerve growth factor (NGF) and brain-derived neurotrophic factor (BDNF), in the cerebral cortex and hippocampus of animal models. Nevertheless, at present, little indication is available on the influence of EE on neurotrophin levels in the cerebellum. Thus, in this study, we exposed male Wistar rats to EE from weaning to 5 months of age and evaluated the production of NGF and BDNF in the cerebellum and compared the neurotrophin changes in this region with those obtained in other brain structures where neurotrophins are produced or transported. We found that in rats exposed to EE from 21st until 140th postnatal day, a significant increase of both BDNF and NGF concentrations was observed in the cerebellum, as compared to rats reared in standard conditions. In addition, cerebellum was the brain region where NGF and BDNF levels were more influenced by EE as compared to the changes observed in other regions. EE also caused a concomitant increase in NGF levels in the striatum while in the same brain region, BDNF levels were reduced. In summary, this study shows that a prolonged exposure to EE is associated with an increase in cerebellar NGF and BDNF production, thus suggesting that the beneficial effects of EE on the cerebellum of adult animals could be mediated, at least in part, by neurotrophins.

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Attention deficit/hyperactivity disorder (ADHD) is the most common neurobehavioral disorder of childhood. There is an increasing need to find objective measures and markers of the disorder in order to assess the efficacy of the therapies and to improve follow-up strategies. Actigraphy is an objective method for recording motor activity and sleep parameters that has been used in many studies in ADHD. Our meta-analysis aimed to assess the current evidence on the role of actigraphy in both the detection of changes in motor activity and in sleep patterns in ADHD. A systematic review was carried out to find studies comparing children with unmedicated ADHD versus controls, using actigraphic measures as an outcome. The primary outcome measures were "sleep duration" and daytime "activity mean". As secondary outcome measures we analyzed "sleep onset latency", "sleep efficiency" and "wake after sleep onset". Twenty-four studies comprising 2179 children were included in this review. We show evidence that ADHD compared to typically developing children present a higher mean activity during structured sessions, a similar sleep duration, and a moderately altered sleep pattern. This study highlights the role of actigraphy as an objective tool for the ambulatory monitoring of sleep and activity in ADHD.