Mineralocorticoid receptor deletion alters spontaneous behavior in an automated home-cage monitoring apparatus.

Mineralocorticoid receptors (MRs) are transcription factors expressed throughout the body and brain, with especially high expression in the hippocampal area CA2. MRs are essential for maintaining the physiological stress response and regulating the hypothalamic-pituitary adrenal (HPA) axis. Further, MRs function through the diurnal modulation of corticosterone activity.

Sex differences in spontaneous behavior and cognition in mice using an automated behavior monitoring system.

Isolation of sex differences as a key characteristic underlying neurobehavioral differentiation is an essential component of studies in neuroscience. The current study sought to address this concern by observing behavioral differences using an automated home cage system for neurobehavioral assessment, a method rapidly increasing in use due to advances in technology and advantages such as reduced handling stress and cross-lab variability. Sex differences in C57BL/6 mice arose for motor activity and circadian-linked behavior, with females being more active compared to males, and males having a stronger anticipatory increase in activity leading up to the onset of the light phase compared to females.

FiPhA: an open-source platform for fiber photometry analysis.

Significance: Fiber photometry (FP) is a widely used technique in modern behavioral neuroscience, employing genetically encoded fluorescent sensors to monitor neural activity and neurotransmitter release in awake-behaving animals. However, analyzing photometry data can be both laborious and time-consuming.

Aim: We propose the fiber photometry analysis (FiPhA) app, which is a general-purpose FP analysis application.

Cholinergic-Sensitive Theta Oscillations in Memory Encoding in Mice.

Cholinergic regulation of hippocampal theta oscillations has long been proposed to be a potential mechanism underlying hippocampus-dependent memory encoding processes. However, cholinergic transmission has been traditionally associated with type II theta under urethane anesthesia. The mechanisms and behavioral significance of cholinergic regulation of type I theta in freely exploring animals is much less clear.

Genetic deletion of α7 nAChRs reduces hippocampal granule and pyramidal cell number in both sexes but impairs pattern separation in males only.

Introduction: Neurogenesis within the dentate gyrus is thought to play an important role in cognitive processes such as reversal learning and pattern separation. The α7 nicotinic acetylcholine receptor (α7 nAChR) is expressed early in newly formed granule cells of the dentate gyrus, though its role in neurogenesis and related cognitive function is not fully understood.

Methods: To better characterize relevant function of α7 nAChRs, we performed unbiased stereology to quantify hippocampal granule cells, pyramidal cells, and total volume and used a touchscreen operant spatial discrimination/reversal task to test pattern separation in a global α7 nAChR knockout mouse line.

FiPhA: An Open-Source Platform for Fiber Photometry Analysis.

Significance: Fiber photometry is a widely used technique in modern behavioral neuroscience, employing genetically encoded fluorescent sensors to monitor neural activity and neurotransmitter release in awake-behaving animals, However, analyzing photometry data can be both laborious and time-consuming.

Aim: We propose the FiPhA (Fiber Photometry Analysis) app, which is a general-purpose fiber photometry analysis application. The goal is to develop a pipeline suitable for a wide range of photometry approaches, including spectrally resolved, camera-based, and lock-in demodulation.

Assessing the importance of sex in a hippocampus-dependent behavioral test battery in C57BL/6NTac mice.

Inclusion of male and female subjects in behavioral neuroscience research requires a concerted effort to characterize sex differences in standardized behavioral assays. Sex differences in hippocampus-dependent assays have been widely reported but are still poorly characterized. In the present study, we conducted a parametric analysis of spontaneous alternation, object recognition, and fear conditioning in a commonly used control strain, C57BL/6NTac.

3D-Printed Capacitive Sensor Objects for Object Recognition Assays.

Object recognition tasks are widely used assays for studying learning and memory in rodents. Object recognition typically involves familiarizing mice with a set of objects and then presenting a novel object or displacing an object to a novel location or context. Learning and memory are inferred by a relative increase in time investigating the novel/displaced object.

Loss of α7 nicotinic acetylcholine receptors in GABAergic neurons causes sex-dependent decreases in radial glia-like cell quantity and impairments in cognitive and social behavior.

The dentate gyrus (DG) is a unique brain structure in that neurons can be generated postnatally and integrated within existing circuitry throughout life. The maturation process of these newly generated neurons (granule cells) is modulated by nicotinic acetylcholine receptors (nAChRs) through a variety of mechanisms such as neural stem pool proliferation, cell survival, signal modulation, and dendritic integration. Disrupted nAChR signaling has been implicated in neuropsychiatric and neurodegenerative disorders, potentially via alterations in DG neurogenesis.

Alcohol Intake Increases in Adolescent C57BL/6J Mice during Intermittent Cycles of Phase-Delayed, Long-Light Conditions.

Unlabelled: Adolescents naturally go to bed and awaken late, but are forced to awaken early for school and work. This leads to "social jetlag", a state of circadian desynchrony (CD), in which internal biological rhythms are out of sync with behavioral rhythms. CD is associated with increased alcohol intake in adults, but has been less well-studied in adolescents.