Nucleus reuniens transiently synchronizes memory networks at beta frequencies.

Episodic memory-based decision-making requires top-down medial prefrontal cortex and hippocampal interactions. This integrated prefrontal-hippocampal memory state is thought to be organized by synchronized network oscillations and mediated by connectivity with the thalamic nucleus reuniens (RE). Whether and how the RE synchronizes prefrontal-hippocampal networks in memory, however, remains unknown.

Dual medial prefrontal cortex and hippocampus projecting neurons in the paraventricular nucleus of the thalamus.

The paraventricular nucleus (PVT) of the midline thalamus is a critical higher-order cortico-thalamo-cortical integration site that plays a critical role in various behaviors including reward seeking, cue saliency, and emotional memory. Anatomical studies have shown that PVT projects to both medial prefrontal cortex (mPFC) and hippocampus (HC). However, dual mPFC-HC projecting neurons which could serve a role in synchronizing mPFC and HC activity during PVT-dependent behaviors, have not been explored.

Discharge characteristics of neurons of nucleus reuniens across sleep-wake states in the behaving rat.

The nucleus reuniens (RE) of the ventral midline thalamus is strongly reciprocally connected with the hippocampus (HF) and medial prefrontal cortex (PFC), serving a critical role in affective and cognitive functioning. While midline thalamic nuclei have been implicated in the modulation of states of arousal and consciousness, few studies have addressed RE's role in behavioral state control. Accordingly, as a first line of investigation, we examined the discharge properties of RE neurons in behaving rats throughout the sleep-wake cycle.

Calretinin and calbindin architecture of the midline thalamus associated with prefrontal-hippocampal circuitry.

The midline thalamus bidirectionally connects the medial prefrontal cortex (mPFC) and hippocampus (HC) creating a unique cortico-thalamo-cortical circuit fundamental to memory and executive function. While the anatomical connectivity of midline thalamus has been thoroughly investigated, little is known about its cellular organization within each nucleus. Here we used immunohistological techniques to examine cellular distributions in the midline thalamus based on the calcium binding proteins parvalbumin (PV), calretinin (CR), and calbindin (CB).

RatHat: A Self-Targeting Printable Brain Implant System.

There has not been a major change in how neuroscientists approach stereotaxic methods in decades. Here, we present a new stereotaxic method that provides an alternative approach to a traditional u-frame stereotaxic device and reduces costs, surgical time, and aids repeatability. The RatHat brain implantation system is a 3D-printable stereotaxic device for rats that is fabricated prior to surgery and fits to the shape of the skull.

Inactivation of nucleus reuniens impairs spatial working memory and behavioral flexibility in the rat.

The hippocampal formation (HF) and medial prefrontal cortex (mPFC) play critical roles in spatial working memory (SWM). The nucleus reuniens (RE) of the ventral midline thalamus is an important anatomical link between the HF and mPFC, and as such is crucially involved in SWM functions that recruit both structures. Little is known, however, regarding the role of RE in other behaviors mediated by this circuit.

A PER3 Polymorphism Interacts with Sleep Duration to Influence Transient Mood States in Women.

Background: Expression of the clock family of genes in the suprachiasmatic nuclei (SCN) regulates the molecular control of circadian timing. Increasing evidence also implicates clock gene activity in the development of mood disorders. In particular, variation in the PER3 clock gene has been shown to influence diurnal preference and sleep homeostasis.

Differential effects of mild chronic stress on cortisol and S-IgA responses to an acute stressor.

While acute stress is adaptive in the short term, chronic stress may interfere with HPA axis functioning and self-regulation that can, in turn, alter the body's immune response. Several studies suggest that acute and chronic stress consistently increase cortisol levels; however, the same cannot be said about S-IgA levels. We tested the effects of a mild chronic stress (an academic exam period), on cortisol and S-IgA responses to an acute stress.