A dorsal hippocampus-prodynorphinergic dorsolateral septum-to-lateral hypothalamus circuit mediates contextual gating of feeding.

Adaptive regulation of feeding depends on linkage of internal states and food outcomes with contextual cues. Human brain imaging has identified dysregulation of a hippocampal-lateral hypothalamic area (LHA) network in binge eating, but mechanistic instantiation of underlying cell-types and circuitry is lacking. Here, we identify an evolutionary conserved and discrete Prodynorphin ()-expressing subpopulation of Somatostatin ()-expressing inhibitory neurons in the dorsolateral septum (DLS) that receives primarily dorsal, but not ventral, hippocampal inputs.

Cognitive control persistently enhances hippocampal information processing.

Could learning that uses cognitive control to judiciously use relevant information while ignoring distractions generally improve brain function, beyond forming explicit memories? According to a neuroplasticity hypothesis for how some cognitive behavioural therapies are effective, cognitive control training (CCT) changes neural circuit information processing. Here we investigated whether CCT persistently alters hippocampal neural circuit function. We show that mice learned and remembered a conditioned place avoidance during CCT that required ignoring irrelevant locations of shock.

Dentate spikes and external control of hippocampal function.

Mouse hippocampus CA1 place-cell discharge typically encodes current location, but during slow gamma dominance (SG), when SG oscillations (30-50 Hz) dominate mid-frequency gamma oscillations (70-90 Hz) in CA1 local field potentials, CA1 discharge switches to represent distant recollected locations. We report that dentate spike type 2 (DS) events initiated by medial entorhinal cortex II (MECII)→ dentate gyrus (DG) inputs promote SG and change excitation-inhibition coordinated discharge in DG, CA3, and CA1, whereas type 1 (DS) events initiated by lateral entorhinal cortex II (LECII)→DG inputs do not. Just before SG, LECII-originating SG oscillations in DG and CA3-originating SG oscillations in CA1 phase and frequency synchronize at the DS peak when discharge within DG and CA3 increases to promote excitation-inhibition cofiring within and across the DG→CA3→CA1 pathway.

Persistent increases of PKMζ in memory-activated neurons trace LTP maintenance during spatial long-term memory storage.

PKMζ is an autonomously active PKC isoform crucial for the maintenance of synaptic long-term potentiation (LTP) and long-term memory. Unlike other kinases that are transiently stimulated by second messengers, PKMζ is persistently activated through sustained increases in protein expression of the kinase. Therefore, visualizing increases in PKMζ expression during long-term memory storage might reveal the sites of its persistent action and thus the location of memory-associated LTP maintenance in the brain.

Effects of regulatory BC1 RNA deletion on synaptic plasticity, learning, and memory.

Nonprotein coding dendritic BC1 RNA regulates translation of mRNAs in neurons. We examined two lines of BC1 knockout mice and report that loss of BC1 RNA exaggerates group I mGluR-stimulated LTD of the Schaffer collateral synapse, with one of the lines showing a much more enhanced DHPG-induced LTD than the other. When the animals were given the hippocampus-synaptic plasticity-dependent active place avoidance task, learning and memory were impaired in the BC1-KO line with the more severely altered DHPG-induced LTD.

Biologically predisposed learning and selective associations in amygdalar neurons.

Modern views on learning and memory accept the notion of biological constraints-that the formation of association is not uniform across all stimuli. Yet cellular evidence of the encoding of selective associations is lacking. Here, conditioned stimuli (CSs) and unconditioned stimuli (USs) commonly employed in two basic associative learning paradigms, fear conditioning and taste aversion conditioning, were delivered in a manner compatible with a functional cellular imaging technique (Arc cellular compartmental analysis of temporal gene transcription by fluorescence in situ hybridization [catFISH]) to identify biological constraints on CS-US convergence at the level of neurons in basolateral amygdala (BLA).

Functional imaging of stimulus convergence in amygdalar neurons during Pavlovian fear conditioning.

Background: Associative conditioning is a ubiquitous form of learning throughout the animal kingdom and fear conditioning is one of the most widely researched models for studying its neurobiological basis. Fear conditioning is also considered a model system for understanding phobias and anxiety disorders. A fundamental issue in fear conditioning regards the existence and location of neurons in the brain that receive convergent information about the conditioned stimulus (CS) and unconditioned stimulus (US) during the acquisition of conditioned fear memory.

Altered cingulate white matter connectivity in panic disorder patients.

Objective: Functional imaging studies of panic disorder subjects suggest an increased activation of the cingulate regions of the brain. Aim of the current study was to explore the white matter connectivity differences between subjects with panic disorder and healthy comparison subjects.

Method: Structural white matter connectivity, as determined from fractional anisotropy (FA) values obtained by diffusion tensor imaging, was assessed for anterior and posterior cingulate regions in 24 panic disorder patients and 24 age and sex-matched healthy comparison subjects.

Diminished rostral anterior cingulate activity in response to threat-related events in posttraumatic stress disorder.

Background: Previous brain imaging studies have reported hyperactivation of the amygdala and hypoactivation of the anterior cingulate in posttraumatic stress disorder (PTSD) patients, which is believed to be an underlying neural mechanism of the PTSD symptoms. The current study specifically focuses on the abnormal activity of the rostral anterior cingulate, using a paradigm which elicits an unexpected processing conflict caused by salient emotional stimuli.

Methods: Twelve survivors (seven men and five women) of the Taegu subway fire in 2003, who later developed PTSD, agreed to participate in this study.

Asymmetrically altered integrity of cingulum bundle in posttraumatic stress disorder.

Previously, our group reported the altered white matter tract integrity of the left anterior cingulate in posttraumatic stress disorder (PTSD) in whole-brain exploration. Current study intended to explore whether the alteration was more prominent in any specific regions of the cingulum bundle. Diffusion tensor images of 21 PTSD subjects and 21 healthy comparison subjects were acquired.

Decreased frontal white-matter integrity in abstinent methamphetamine abusers.

This study explored differences in frontal white-matter (WM) integrity between methamphetamine (MA) abusers and healthy comparison subjects using diffusion tensor imaging (DTI). Fractional anisotropy (FA) values, which indicate WM integrity, were calculated for regions-of-interest in frontal WM on diffusion tensor images of 32 MA abusers and 30 healthy comparison subjects. Frontal executive functions were also assessed by the Wisconsin Card Sorting test (WCST).

The relationship between the biogenetic temperament and character and psychopathology in adolescents.

Background: This study was conducted to investigate the relationship between patterns of temperament and character and self-reported psychopathology in adolescents from the community.

Sampling And Methods: The Junior Temperament and Character Inventory (JTCI) and Youth Self-Report (YSR) instruments were administered to 623 Korean middle school students (boys/girls = 331/292; age = 13.3 +/- 0.

Biogenetic temperament and character and attention deficit hyperactivity disorder in Korean children.

Background: The objective of this study was to evaluate the relationship between symptoms of attention deficit hyperactivity disorder (ADHD) and biogenetic temperament, as assessed by the Junior Temperament and Character Inventory (JTCI) in Korean elementary school children.

Sampling And Methods: Five hundred and sixteen elementary school students (254 boys and 262 girls; age range 9-14 years, mean age 11.0 +/- 1.

Increased white matter hyperintensities in male methamphetamine abusers.

Background: The current study was conducted to compare the prevalence, severity, and location of white matter signal hyperintensities (WMH) on brain magnetic resonance (MR) imaging in methamphetamine (MA) abusers.

Methods: Thirty-three MA abusers and 32 age- and gender-matched healthy comparison subjects were studied. Axial T-2 weighted images and fluid attenuated inversion recovery axial images were obtained using 3.

Prefrontal grey-matter changes in short-term and long-term abstinent methamphetamine abusers.

Authors explored grey-matter density in 29 methamphetamine abusers and 20 healthy comparison subjects using voxel-based morphometry. Grey-matter density changes and performances on the Wisconsin Card Sorting test (WCST) were also compared between 11 short-term (<6 months) and 18 long-term (>or=6 months) abstinent methamphetamine abusers. Methamphetamine abusers had lower grey-matter density in the right middle frontal cortex (corrected p<0.

Shape changes of the corpus callosum in abstinent methamphetamine users.

The objective of the current study was to evaluate structural changes of the corpus callosum (CC) in abstinence methamphetamine (MA) users. Shape and size of the CC in 27 MA users were compared to those of 18 healthy comparison subjects. To define the local curvature and width of the CC, medial model-based shape analysis was performed using CC skeletons extracted from a distance map.

Fractional anisotropy-based divisions of midsagittal corpus callosum.

The authors first divided the midsagittal corpus callosum of 22 healthy volunteers using three different subdivision methods: Witelson's geometric subdivision, boundary model-based subdivision, and medial model-based subdivision. Next, subdivisions of the corpus callosum were clustered on the basis of homogeneity of the fractional anisotropy values as produced from diffusion tensor images. Nine subregions of corpus callosum, similar in location and size, were successfully clustered when medial model-based or boundary model-based subdivisions were applied.

Attention deficit hyperactivity symptoms and internet addiction.

The objective of this study was to evaluate the relationship between attention deficit-hyperactivity/impulsivity symptoms and Internet addiction. In total, 535 elementary school students (264 boys, 271 girls; mean age, 11.0 +/- 1.