Selective Disruption of Perineuronal Nets in Mice Lacking Crtl1 is Sufficient to Make Fear Memories Susceptible to Erasure.

The ability to store, retrieve, and extinguish memories of adverse experiences is an essential skill for animals' survival. The cellular and molecular factors that underlie such processes are only partially known. Using chondroitinase ABC treatment targeting chondroitin sulfate proteoglycans (CSPGs), previous studies showed that the maturation of the extracellular matrix makes fear memory resistant to deletion.

Mir-132/212 is required for maturation of binocular matching of orientation preference and depth perception.

MicroRNAs (miRNAs) are known to mediate post-transcriptional gene regulation, but their role in postnatal brain development is still poorly explored. We show that the expression of many miRNAs is dramatically regulated during functional maturation of the mouse visual cortex with miR-132/212 family being one of the top upregulated miRNAs. Age-downregulated transcripts are significantly enriched in miR-132/miR-212 putative targets and in genes upregulated in miR-132/212 null mice.

Experience-dependent DNA methylation regulates plasticity in the developing visual cortex.

DNA methylation is an epigenetic repressor mark for transcription dynamically regulated in neurons. We analyzed visual experience regulation of DNA methylation in mice and its involvement in ocular dominance plasticity of the developing visual cortex. Monocular deprivation modulated the expression of factors controlling DNA methylation and exerted opposite effects on DNA methylation and hydroxymethylation in specific plasticity genes.

ERK pathway activation bidirectionally affects visual recognition memory and synaptic plasticity in the perirhinal cortex.

ERK 1,2 pathway mediates experience-dependent gene transcription in neurons and several studies have identified its pivotal role in experience-dependent synaptic plasticity and in forms of long term memory involving hippocampus, amygdala, or striatum. The perirhinal cortex (PRHC) plays an essential role in familiarity-based object recognition memory. It is still unknown whether ERK activation in PRHC is necessary for recognition memory consolidation.

Epigenetic treatments of adult rats promote recovery from visual acuity deficits induced by long-term monocular deprivation.

In mammals the development of the visual system may be altered during a sensitive period by modifying the visual input to one or both eyes. These plastic processes are reduced after the end of the sensitive period. It has been proposed that reduced levels of plasticity are at the basis of the lack of recovery from early visual deprivation observed in adult animals.

Involvement of the parietal cortex in perceptual learning (Eureka effect): an interference approach using rTMS.

The neural mechanisms underlying perceptual learning are still under investigation. Eureka effect is a form of rapid, long-lasting perceptual learning by which a degraded image, which appears meaningless when first seen, becomes recognizable after a single exposure to its undegraded version. We used online interference by focal 10-Hz repetitive transcranial magnetic stimulation (rTMS) to evaluate whether the parietal cortex (PC) is involved in Eureka effect, as suggested by neuroimaging data.