Distinct Progressions of Neuronal Activity Changes Underlie the Formation and Consolidation of a Gustatory Associative Memory.

Acquiring new memories is a multistage process. Numerous studies have convincingly demonstrated that initially acquired memories are labile and are stabilized only by later consolidation processes. These multiple phases of memory formation are known to involve modification of both cellular excitability and synaptic connectivity, which in turn change neuronal activity at both the single neuron and ensemble levels. However, the specific mapping between the known phases of memory and the changes in neuronal activity at different organizational levels-the single-neuron, population representations, and ensemble-state dynamics-remains unknown. Here we address this issue in the context of conditioned taste aversion learning by continuously tracking gustatory cortex neuronal taste responses in alert male and female rats during the 24 h following a taste-malaise pairing. We found that the progression of activity changes depends on the neuronal organizational level: whereas the population response changed continuously, the population mean response amplitude and the number of taste-responsive neurons only increased during the acquisition and consolidation phases. In addition, the known quickening of the ensemble-state dynamics associated with the faster rejection of harmful foods appeared only after consolidation. Overall, these results demonstrate how complex dynamics in the different representational levels of cortical activity underlie the formation and stabilization of memory within the cortex.SIGNIFICANCE STATEMENT Memory formation is a multiphased process; early acquired memories are labile and consolidate to their stable forms over hours and days. The progression of memory is assumed to be supported by changes in neuronal activity, but the mapping between memory phases and neuronal activity changes remains elusive. Here we tracked cortical neuronal activity over 24 h as rats acquired and consolidated a taste-malaise association memory, and found specific differences between the progression at the single-neuron and populations levels. These results demonstrate how balanced changes on the single-neuron level lead to changes in the network-level representation and dynamics required for the stabilization of memories.

Disk Battery as a Vaginal Foreign Body in a Five-Year-Old Preadolescent Child.

The self-introduction of batteries into the vagina is exceedingly infrequent among preadolescents, with only six cases have been recorded in the English-language PubMed-indexed literature. Herein, we present the case of a five-year-old female child who presented with an 18-month history of recurrent ill-smelling vaginal discharge. Pelvic radiograph displayed a radio-opaque object, most likely representing a disk battery inside her vagina. Vaginoscopy showed a 1.2 cm disk battery that was removed from the right posterior vaginal fornix. Four weeks later, the child was doing well and symptom-free. Although rare, vaginal foreign bodies should be considered in the differential diagnosis in preadolescent girls presenting with chronic and recurrent vaginal discharge. Vaginoscopy is a useful tool diagnostically and therapeutically. A clinical summary of all PubMed-indexed cases of batteries as vaginal FBs in children is provided (n=6).

Effects of education and social contact on mental health-related stigma among high-school students.

Poor knowledge and stigma toward people with mental illness negatively affect intentions to seek help among adolescents. The study aimed to assess the impact of three school-based interventions and to explore whether positive changes in attitudes were linked to more favorable changes in desire for social distance and seeking help. A total of 221 upper secondary students were allocated to three interventions: 1. social contact; 2. Mental Health Literacy (MHL) conducted by clinicians; 3. MHL conducted by dis-peer instructors. Measures of knowledge, attitudes, views on empowerment and recovery, willingness to interact, and help seeking were collected. Generalized Estimating Equations and Structural Equation Modeling (SEM) were used to evaluate scores differences between interventions through time, and to test the interrelationships between knowledge, attitudes variables and the two outcomes of interest. Findings showed that all groups improved in knowledge, attitudes, empowerment, willingness to interact, and seeking help. SEM revealed that the increase in knowledge was significantly associated with the General attitudes toward people with mental illness construct that, in turn, was positively associated with willingness to interact and seeking help. Results encourage the use of anti-stigma interventions in order to decrease negative attitudes toward mental illness and improve behavioral intentions among students.