Topic: muscimol

Midbrain dopamine (DA) neurons are thought to be critical for reinforcement learning as well as motor control. One important target for DA neurons is the striatum where different subregions are innervated by different midbrain DA neurons. A wealth of evidence suggests that DA release in the ventral striatum acts as a reward prediction error (RPE) to support cue-outcome associations while DA manipulations in the dorsolateral striatum produce gross effects on movement. The dorsomedial striatum (DMS), located between the ventral and dorsolateral striatum, may represent an intermediate position al

While temporal control is crucial for the generation of a wide range of sensorimotor tasks, its underlying mechanisms remain unclear. Like human speech, birdsong relies on a tight muscle coordination, and songbirds have proved to be an outstanding model to study the sequential pattern of neuronal activity encoding action timing. In male zebra finches, the premotor nucleus HVC is responsible for the precise control of song tempo. Current computational models of HVC rely on synfire chains, a purely feedforward network model that can account for HVC sequential activity. Synfire chains are however

Autism spectrum disorder (ASD) is a term used to describe a wide variety of neurodevelopmental disorders that share manifestations and symptoms including intellectual disabilities, social impairments, delayed speech development and repetitive behaviors. Different animal models of ASD share similar electrophysiological and morphological aberrations at the neuronal level. In particular, previous studies have shown that the developmental maturation of GABAergic circuitry appears altered leading to an excitation/inhibition imbalance in the adult. During neurotransmission, the polarity of the GABAe

Memory consolidation is promoted by sleep. However, there is also evidence for consolidation into long-term memory during wakefulness via processes that preferentially affect nonhippocampal representations. We compared, in rats, the effects of 2-h postencoding periods of sleep and wakefulness on the formation of long-term memory for objects and their associated environmental contexts. We employed a novel-object recognition (NOR) task, using object exploration and exploratory rearing as behavioral indicators of these memories. Remote recall testing (after 1 wk) confirmed significant long-term N

Understanding the mechanisms of statistical learning, where organisms infer structure from sensory observations without explicit instruction, is crucial in comprehending how the brain processes and responds to complex environments. This work explores the innate capabilities of both humans and mice to discern environmental regularities, focusing on the role of the hippocampus in this implicit learning processes. We use pupillometry to measure whether animals can detect and track patterns in rapidly unfolding sounds. The study leverages a novel comparative behavioural paradigm, termed X-detectio

Muscimol is a potent agonist of inhibitory GABAA-receptors, which are a heterogenous family of pentameric complexes. Muscimol is considered to bind to all receptor subtypes at the orthosteric β+/α- interface. In one of our recent publications, we observed that the antipsychotic drugs clozapine (CLZ), loxapine (LOX) and chlorpromazine (CPZ) showed diverging results in displacing 3H-muscimol. While a complete displacement could be observed by bicuculline (BIC), and no displacement with CPZ, the compounds CLZ and LOX could only incompletely compete with the radioligand. In addition, the dose-resp

Social interaction is a dynamic process wherein individuals exert reciprocal influence on one another. This process encompasses diverse types of behaviors which are infrequently delineated and examined distinctly. Moreover, while the quest for the social brain has mainly focused on the cerebrum, recent evidence has unveiled the potential engagement of cerebellar mechanisms in the regulation of social interactions. In this light, we microinfused muscimol (a GABAa receptor agonist) or saline into the deep cerebellar nuclei (DCN) of mice and measured their social behaviors in a modified version o

Reversal learning, a form of cognitive flexibility disrupted in many brain disorders, involves switching from one response to another when the reward contingencies of the responses are reversed. The hippocampus, especially the ventral hippocampus (VH), connects to fronto-striatal circuits regulating reversal learning. Previous studies reported that hippocampal lesions impaired, whereas chemogenetic activation of VH facilitated, reversal learning acquisition in animal models. However, there is limited evidence on how VH activity affects distinct stages of reversal learning. Therefore, we examin