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Fear generalization is one of the main symptoms of posttraumatic stress disorder. In rodents, the anterior cingulate cortex (ACC) and the hippocampus (HPC) control the expression of contextual fear memory generalization. Consistently, ACC projections to the ventral HPC contribute to contextual fear generalization. However, the roles of ACC projections to the dorsal HPC (dHPC) in fear generalization are unclear, although the dHPC is required for the retrieval of recent contextual fear memory. To investigate these roles, we examined the effects of optogenetic silencing and stimulation of these projections in contextual fear generalization at the recent and remote time points. Mice underwent contextual fear conditioning and, at 1 or 28 d later, were tested in the conditioned chamber, a novel context, or a similar context. Optogenetic activation of these projections induced higher freezing in mice in the novel context compared with the control group at a recent (1-d), but not remote (28-d), time point following conditioning, suggesting that activation of this pathway enhances contextual fear generalization. In contrast, optogenetic inactivation of these projections induced lower freezing in the similar context compared with the control group at a recent, but not remote, time point, suggesting that inactivation of this pathway impaired contextual fear generalization. These observations suggest that the ACC to the dHPC projections positively regulate the expression of contextual fear generalization when contextual fear memory is recent.

Aim: A reduced mismatch negativity (MMN) response is a promising electrophysiological endophenotype of schizophrenia that reflects neurocognitive impairment. Dopamine dysfunction is associated with symptoms of schizophrenia. However, whether the dopamine system is involved in MMN impairment remains controversial. In this study, we investigated the effects of the dopamine D2‐like receptor agonist quinpirole on mismatch responses to sound frequency changes in an animal model. Methods: Event‐related potentials were recorded from electrocorticogram electrodes placed on the auditory and frontal cortices of freely moving rats using a frequency oddball paradigm consisting of ascending and equiprobable (ie, many standards) control sequences before and after the subcutaneous administration of quinpirole. To detect mismatch responses, difference waveforms were obtained by subtracting nondeviant control waveforms from deviant waveforms. Results: Here, we show the significant effects of quinpirole on frontal mismatch responses to sound frequency deviations in rats. Quinpirole delayed the frontal N18 and P30 mismatch responses and reduced the frontal N55 MMN‐like response, which resulted from the reduction in the N55 amplitude to deviant stimuli. Importantly, the magnitude of the N55 amplitude was negatively correlated with the time of the P30 latency in the difference waveforms. In contrast, quinpirole administration did not clearly affect the temporal mismatch responses recorded from the auditory cortex. Conclusion: These results suggest that the disruption of dopamine D2‐like receptor signaling by quinpirole reduces frontal MMN to sound frequency deviations and that delays in early mismatch responses are involved in this MMN impairment. [ABSTRACT FROM AUTHOR]

The transcription profile of microglia related to fear conditioning remains unclear. Here, we used Illumina MouseWG-6v2 microarrays to investigate the gene transcription changes in microglia and peripheral monocytes after contextual fear conditioning of C57BL/6 J mice. Mice were trained with or without a single minimized footshock stimulation (0-s or 2-s, 0.4 mA) and re-exposed to the training context without footshock for three different durations 24 h later: 0 min (FS0), 3 min (FS3), or 30 min (FS30). Whole brain microglia and peripheral monocytes were prepared 24 h after re-exposure using a neural tissue dissociation kit, including non-footshock controls for two re-exposure durations (Con3 and Con30). The data can be valuable for researchers interested in glial cells and neurotransmission studies and are related to the research article "Contextual fear conditioning regulates synapse-related gene transcription in mouse microglia"., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2022 The Author(s).)

Fear memory is defined as the associative (fear-conditioned) memory between the context of a fear experience (conditioned stimulus) and fear itself (unconditioned stimulus). Re-exposure to the conditioned context retrieves the fear memory and triggers a fear response. Fear memories have been observed in both nematodes and humans, suggesting common neural mechanisms. Studies using rodents and other animal models have identified the mechanisms of fear memory processes, such as consolidation, retrieval, reconsolidation, destabilization, and extinction, at the molecular, cellular, circuit, and behavioral levels. This review introduces fear memory processes and their mechanisms.

(Objectives) This study aimed to evaluate the surgical outcomes and functional parameters of lower urinary tract and bowel symptoms in patients who have undergone robot-assisted sacrocolpopexy (RASC) due to pelvic organ prolapse. (Patients and methods) This retrospective study included 110 consecutive RASC cases in the urology department of Ageo Central General Hospital, Japan, from November 2020 to October 2021. The medical records of these patients were retrieved. Data on uroflowmetry, post-void residual urine test, and self-administered questionnaires on urination and defecation were assessed. (Results) The mean operating time was 146 min, and the estimated blood loss was 14.8 ml. The intraoperative, postoperative, and severe complication rates of cases classified as Clavien-Dindo grade IIIa or higher were 0%, 9.1%, and 0%, respectively. The maximum flow rate and post-void residual volume of urine significantly improved after the operation. Similarly, the quality of life (QOL) scores and overactive bladder symptom score (OABSS), as well as the responses for the International Consultation on Incontinence Questionnaire-Short Form (ICIQ-SF) and Urinary Distress Inventory-6 (UDI-6), significantly improved one month after the operation and were sustained for six months. On the other hand, the total scores from the Constipation Scoring System (CSS) and the subscales of the Patient Assessment of Constipation (PAC) -QOL worsened. These scores, except for those of the PAC-QOL satisfaction subscale recovered to the preoperative levels; the PAC-QOL satisfaction subscale scores significantly improved six months postoperatively. The rates of de novo overactive bladder (OAB), stress urinary incontinence (SUI), and constipation one month postoperatively were 8%, 33%, and 10%, respectively. (Conclusions) RASC was performed safely in our institution with acceptable postoperative lower urinary tract and bowel outcomes.