Medial septal cholinergic neurotransmission is essential for social memory in mice.

Social memory, a fundamental component of social behavior, is essential for the recognition and recall of familiar and novel animals/humans which is disrupted in several neuropsychiatric disorders. Although hippocampal circuitry is crucial for social memory, the role of extra-hippocampal regions in this behavior remains elusive. Here, we identified the physiological link between medial septal dependent cholinergic theta oscillations in the hippocampus and social memory behavior.

Extrahippocampal Contributions to Social Memory: The Role of Septal Nuclei.

Social memory, the ability to recognize and remember individuals within a social group, is crucial for social interactions and relationships. Deficits in social memory have been linked to several neuropsychiatric and neurodegenerative disorders. The hippocampus, especially the circuit that links dorsal CA2 and ventral CA1 neurons, is considered a neural substrate for social memory formation.

Compulsive-like Behaviors in Amyloid-β 1-42-Induced Alzheimer's Disease in Mice Are Associated With Hippocampo-cortical Neural Circuit Dysfunction.

Background: In addition to memory deficits, patients with Alzheimer's disease (AD) experience neuropsychiatric disturbances. Recent studies have suggested the association of obsessive-compulsive disorder with the early stages of AD. However, there is a lack of understanding of the neurobiological underpinnings of compulsive-like behaviors at the neuronal circuit level and their relationship with AD.

A comprehensive review of protein misfolding disorders, underlying mechanism, clinical diagnosis, and therapeutic strategies.

Introduction: Proteins are the most common biological macromolecules in living system and are building blocks of life. They are extremely dynamic in structure and functions. Due to several modifications, proteins undergo misfolding, leading to aggregation and thereby developing neurodegenerative and systemic diseases.

Apathy in Alzheimer's disease: A neurocircuitry based perspective.

In addition to memory deficits and other cognitive disturbances, patients with Alzheimer's disease (AD) experience neuropsychiatric symptoms, notably apathy, which is a state of impaired motivation observed by deficits in goal directed behavior. Apathy is a multifaceted neuropsychiatric condition and appears to be a prognostic indicator, correlating with the progression of AD. Strikingly, recent studies point out that the neurodegenerative pathology of AD may drive apathy independent of cognitive decline.

Hemispherically lateralized rhythmic oscillations in the cingulate-amygdala circuit drive affective empathy in mice.

Observational fear, a form of emotional contagion, is thought to be a basic form of affective empathy. However, the neural process engaged at the specific moment when socially acquired information provokes an emotional response remains elusive. Here, we show that reciprocal projections between the anterior cingulate cortex (ACC) and basolateral amygdala (BLA) in the right hemisphere are essential for observational fear, and 5-7 Hz neural oscillations were selectively increased in those areas at the onset of observational freezing.

Phytochemical based Modulation of Endoplasmic Reticulum Stress in Alzheimer's Disease.

Alzheimer's disease (AD) is a severe progressive neurodegenerative condition that shows misfolding and aggregation of proteins contributing to a decline in cognitive function involving multiple behavioral, neuropsychological, and cognitive domains. Multiple epi (genetic) changes and environmental agents have been shown to play an active role in ER stress induction. Neurodegeneration due to endoplasmic reticulum (ER) stress is considered one of the major underlying causes of AD.

Theta and gamma oscillatory dynamics in mouse models of Alzheimer's disease: A path to prospective therapeutic intervention.

Understanding the neural basis of cognitive deficits, a key feature of Alzheimer's disease (AD), is imperative for achieving the therapy of the disease. Rhythmic oscillatory activities in neural systems are a fundamental mechanism for diverse brain functions, including cognition. In several neurological conditions like AD, aberrant neural oscillations have been shown to play a central role.

Oxidative Stress in Cognitive and Epigenetic Aging: A Retrospective Glance.

Brain aging is the critical and common factor among several neurodegenerative disorders and dementia. Cellular, biochemical and molecular studies have shown intimate links between oxidative stress and cognitive dysfunction during aging and age-associated neuronal diseases. Brain aging is accompanied by oxidative damage of nuclear as well as mitochondrial DNA, and diminished repair.

Yin-and-yang bifurcation of opioidergic circuits for descending analgesia at the midbrain of the mouse.

In the descending analgesia pathway, opioids are known to disinhibit the projections from the periaqueductal gray (PAG) to the rostral ventromedial medulla (RVM), leading to suppression of pain signals at the spinal cord level. The locus coeruleus (LC) has been proposed to engage in the descending pathway through noradrenergic inputs to the spinal cord. Nevertheless, how the LC is integrated in the descending analgesia circuit has remained unknown.

Medial septal GABAergic projection neurons promote object exploration behavior and type 2 theta rhythm.

Exploratory drive is one of the most fundamental emotions, of all organisms, that are evoked by novelty stimulation. Exploratory behavior plays a fundamental role in motivation, learning, and well-being of organisms. Diverse exploratory behaviors have been described, although their heterogeneity is not certain because of the lack of solid experimental evidence for their distinction.

Extrasynaptic GABAA receptors in mediodorsal thalamic nucleus modulate fear extinction learning.

Background: The gamma-amino-butyric acid (GABA) system is a critical mediator of fear extinction process. GABA can induce "phasic" or "tonic" inhibition in neurons through synaptic or extrasynaptic GABAA receptors, respectively. However, role of the thalamic "tonic GABA inhibition" in cognition has not been explored.

Behavioral deficit and decreased GABA receptor functional regulation in the hippocampus of epileptic rats: effect of Bacopa monnieri.

In the present study, alterations of the General GABA and GABA(A) receptors in the hippocampus of pilocarpine-induced temporal lobe epileptic rats and the therapeutic application of Bacopa monnieri and its active component Bacoside-A were investigated. Bacopa monnieri (Linn.) is a herbaceous plant belonging to the family Scrophulariaceae.

Phospholipase C beta 4 in the medial septum controls cholinergic theta oscillations and anxiety behaviors.

Anxiety is among the most prevalent and costly diseases of the CNS, but its underlying mechanisms are not fully understood. Although attenuated theta rhythms have been observed in human subjects with increased anxiety, no study has been done on the possible physiological link between these two manifestations. We found that the mutant mouse for phospholipase C beta 4 (PLC-beta 4(-/-)) showed attenuated theta rhythm and increased anxiety, presenting the first animal model for the human condition.

Decreased muscarinic M1 receptor gene expression in the cerebral cortex of streptozotocin-induced diabetic rats and Aegle marmelose leaf extract's therapeutic function.

Aim: In the present study we have investigated the changes in the total muscarinic and muscarinic M1 receptor ([(3)H]QNB) binding and gene expression in the cerebral cortex of streptozotocin (STZ) induced diabetic, insulin and aqueous extract of Aegle marmelose leaf treated diabetic rats.

Materials And Methods: Diabetes was induced in rats by intrafemoral injection of streptozotocin. Aegle marmelose leaves was given orally to one group of rats at a dosage of 1g/kg body weight per day for fourteen days.