Synaptic properties of newly generated granule cells support sparse coding in the adult hippocampus.

Synaptic properties of newly generated granule cells support sparse coding in the adult hippocampus. Behav Brain Res. 2019 Jun 12;:112036 Authors: Lodge M, Bischofberger J Abstract In the adult hippocampus new neurons are continuously generated throughout life and integrate into the existing network via the formation of thousands of new synapses. Adult-born granule cells are known to improve learning and memory at about 3-6 weeks post mitosis by enhancing the brains ability to discriminate similar memory items. However, the underlying mechanisms are still controversial. Here we review the distinct functional properties of the newborn young neurons, including enhanced excitability, reduced GABAergic inhibition, NMDA-receptor dependent electrogenesis and enhanced synaptic plasticity. Although these cellular properties provide a competitive advantage for synapse formation, they do not generate 'hyperactivity' of young neurons. By contrast, in vivo evidence from immediate early gene expression and calcium imaging indicates that young neurons show sparse activity during learning. Similarly, in vitro data show a low number of high-impact synapses, leading to activation young cells by distinct subsets of afferent fibers with minimal overlap. Overall, the enhanced excitability of young cells does not generate hyperactivity but rather counterbalance the low number of excitatory input synapses. Finally, sparse coding in young neurons has been shown to be crucial f...
Source: Behavioural Brain Research - Category: Neurology Authors: Tags: Behav Brain Res Source Type: research

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CONCLUSIONS Our findings showed that about 20% of the youths had at least one mental disorder. However, this prevalence is underestimated since other relevant mental disorders were not assessed. Mental disorders were associated with higher suicide risk, especially the comorbidity between them.
Source: Revista de Saude Publica - Category: International Medicine & Public Health Source Type: research
In conclusion, CWE seem to benefit from interventions and behavior modification techniques first developed for children with ADHD.
Source: Epilepsy and Behavior - Category: Neurology Source Type: research
Condition:   Attention Deficit Disorder With Hyperactivity Interventions:   Drug: Methylphenidate;   Drug: Lisdexamfetamine;   Drug: Atomoxetine;   Drug: Amphetamine;   Drug: Dextroamphetamine Sponsor:   Janssen Research & Development, LLC Recruiting
Source: ClinicalTrials.gov - Category: Research Source Type: clinical trials
Publication date: Available online 19 October 2019Source: Progress in Neuro-Psychopharmacology and Biological PsychiatryAuthor(s): Melissa M. Meeking, Derrick F. MacFabe, Jennifer R. Mepham, Kelly A. Foley, Lisa J. Tichenoff, Francis H. Boon, Martin Kavaliers, Klaus-Peter OssenkoppAbstractAutism spectrum disorders (ASD) are a set of neurodevelopmental disorders characterized by abnormal social interactions, impaired language, and stereotypic and repetitive behaviours. Among genetically susceptible subpopulations, gut and dietary influences may play a role in etiology. Propionic acid (PPA), produced by enteric gut bacteria,...
Source: Progress in Neuro Psychopharmacology and Biological Psychiatry - Category: Psychiatry Source Type: research
In Reply We thank Cui and Liu as well as Dravland for their thoughtful comments about our work. Cui and Liu point out that we did not include a Chinese study by Zheng et al. This omission is unfortunate because it would have partly balanced the overrepresentation of North American data. The study is interesting because although in a cohort of 153 children aged 6 to 12 years the chosen dose range for titration of osmotic-release oral system methylphenidate (OROS-MPH) was 18 to 54 mg/d, after 12 weeks, the mean titrated dose was only 22.8 mg/d, and there were no children receiving 54 mg. Whether this reflects differences in ...
Source: JAMA Pediatrics - Category: Pediatrics Source Type: research
This article reports on 11 randomized clinical trials including 1304 participants treated with methylphenidate and 887 control individuals and 38 cohort studies including 5524 participants. The evidence from this meta-analysis showed that a range of maximum doses for methylphenidate was recommended in different clinical studies and no discernable scientific justification for any particular dose was offered. This meta-analysis is an advanced study to summarize and compare findings from clinical studies. However, there might be some limitations in this study.
Source: JAMA Pediatrics - Category: Pediatrics Source Type: research
Conclusions: Children with ADHD may suffer from sleep breathing problems and daytime sleepiness, as reported by their parents, even when their total sleep time and sleep efficiency are not affected. It seems that sleep in this population does not largely vary as a function of the ADHD presentation. Sleep in children with ADHD evolves with age.ResumenAntecedentes/ObjetivoExaminar los patrones de sueño subjetivos y objetivos de niños con diferentes presentaciones del Trastorno por déficit de atención e hiperactividad (TDAH). Método: Se evaluaron 92 niños (29 TDAH-inatento [TDAH-I)], ...
Source: International Journal of Clinical and Health Psychology - Category: Psychiatry & Psychology Source Type: research
es EL Abstract Considering the recognized role of thyroid hormones on the cardiovascular system during health and disease, we hypothesized that type 2 deiodinase (D2) activity, the main activation pathway of thyroxine (T4)-to-triiodothyronine (T3), could be an important site to modulate thyroid hormone status, which would then constitute a possible target for β-adrenergic blocking agents in a myocardial infarction (MI) model induced by left coronary occlusion in rats. Despite a sustained and dramatic fall in serum T4 concentrations (60-70%), the serum T3 concentration fell only transiently in the first week p...
Source: Braz J Med Biol Res - Category: Research Authors: Tags: Braz J Med Biol Res Source Type: research
Psychostimulants are one of the safest and most efficacious pharmacological interventions for a psychiatric disorder. In 1999 the groundbreaking Multimodal Treatment of ADHD (MTA) study set the standard of care for long-term treatment for children with attention-deficit/hyperactivity disorder (ADHD).1 Since then, stimulant use has increased substantially around the world.2 Because ADHD is a chronic condition, guidelines recommend re-evaluating the continued use of stimulant medications over many years in order to assess symptom relief and associated poor academic, social and work-life functioning.
Source: Journal of the American Academy of Child and Adolescent Psychiatry - Category: Psychiatry Authors: Tags: Editorial Source Type: research
CONCLUSIONS: Anterior hippocampal hyperactivity in early-psychosis patients appears to limit effective recruitment of this region during task performance. These findings provide novel support for the anterior hippocampus as a therapeutic target in the treatment of cognitive deficits in psychosis. PMID: 31623459 [PubMed - as supplied by publisher]
Source: The American Journal of Psychiatry - Category: Psychiatry Authors: Tags: Am J Psychiatry Source Type: research
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