Interaction between limbic circuits and basal ganglia in behaviour inhibition

Changing behaviour in response to changing internal and external situations is crucial for survival. In particular, we need to inhibit ongoing, unwanted or inappropriate behaviour. Behavioural inhibition includes inhibition of an ongoing action, thought or emotion (in the basal ganglia; BG). But it can also involve inhibition of goals (in the limbic system) – which is much slower. A better understanding of the neural mechanisms controlling inhibition of behaviour is important for cognitive neuroscience, particularly in relation to problems of impulsivity. This thesis aims to fill a gap in our understanding of behavioural inhibition and to elucidate the parallel circuits that control its different types. Several lesion, neuroimaging, and electrophysiological studies have been conducted to understand the role of brain regions in behavioural inhibition. Previous research has identified roles for the BG, orbitofrontal cortex (OFC) and hippocampus (HPC) in generation of various frequencies of rhythmicity during behavioural inhibition. However, the interaction between these regions has not been studied in rats during simple learning, simple action inhibition and complex behavioural inhibition. The stop signal task (SST) is the most commonly used paradigm to study simple behavioural inhibition. In this study, I recorded local field potentials (LFPs) simultaneously from BG (particularly striatum; STR and subthalamic nucleus; STN), OFC and HPC while rats performed the SST to assess how simple action inhibition differs from complex behavioural inhibition linked to goal-conflict. The data show increases in the STN LFP spectral beta power and coherence with OFC after stopping an ongoing action (simple stopping). In contrast, stop failure increased HPC-STN coherent activity in the theta frequency band. In addition to the HPC, goal-conflict also activates OFC and STN during high conflict at higher theta frequency (11-12 Hz). In contrast, the conflict induced coherence effect was seen at lower theta frequencies (5-8 Hz) between two pairs of STN (HPC-STN and OFC-STN). The results from the various experiments suggest that part of BG (STR and STN) and limbic system work in parallel and in a dynamic way for learning, response inhibition and complex behavioural inhibition (approach-avoidance conflict). The HPC is not involved in simple motor learning but may receive motivational information form STR and OFC. Simple inhibition involves mainly cortex and BG, while complex inhibition during goal-conflict also involves HPC, OFC and STN. Interestingly, goal inhibition appears to access circuits involved in simple stopping via OFC. In conclusion, functional connections between limbic and BG provides an adaptive control, so that goal selection (limbic structures) and programming of motor action (BG) can operate in parallel

Mapping sheep to human brain: The need for a sheep brain atlas

A brain atlas is essential for understanding the anatomical relationship between neuroanatomical structures. Standard stereotaxic coordinates and reference systems have been developed for humans, non-human primates and small laboratory animals to contribute to translational neuroscience research. Despite similar neuroanatomical and neurofunctional features between the sheep and human brain, little is known of the sheep brain stereotaxy, and a detailed sheep atlas is scarce. Here, we briefly discuss the value of using sheep in neurological research and the paucity of literature concerning the coordinates system during neurosurgical approaches. Recent advancements such as computerized tomography, positron emission tomography, magnetic resonance imaging, functional magnetic resonance imaging and diffusion tensor imaging are used for targeting and localizing the coordinates and brain areas in humans. Still, their application in sheep is rare due to the lack of a 3D stereotaxic sheep atlas by which to map sheep brain structures to its human counterparts. More recently, a T1- and T2-weighted high-resolution MRI 3D stereotaxic atlas of the sheep brain has been generated, however, the journey to create a sheep brain atlas by which to map directly to the human brain is still uncharted. Therefore, developing a detailed sheep brain atlas is valuable for the future to facilitate the use of sheep as a large animal experimental non-primate model for translational neurological research

The Availability of Emergency Obstetric Care in Birthing Centres in Rural Nepal: A Cross-sectional Survey.

OBJECTIVE: The purpose of this health system's study is to assess the availability of Emergency Obstetric Care (EmOC) services in birthing centres in Taplejung District of eastern Nepal. METHODS: A cross-sectional survey was conducted in 2018 in all 16 public health facilities providing delivery services in the district. Data collection comprised: (1) quantitative data collected from health workers; (2) observation of key items; and (3) record data extracted from the health facility register. Descriptive statistics were used to calculate readiness scores using unweighted averages. RESULTS: Although key health personnel were available, EmOC services at the health facilities assessed were below the minimum coverage level recommended by the World Health Organisation. Only the district hospital provided the nine signal functions of Comprehensive EmOC. The other fifteen had only partially functioning Basic EmOC facilities, as they did not provide all of the seven signal functions. The essential equipment for performing certain EmOC functions was either missing or not functional in these health facilities. CONCLUSIONS FOR PRACTICE: The Ministry of Health and Population and the federal government need to ensure that the full range of signal functions are available for safe deliveries in partially functioning EmOC health facilities by addressing the issues related to training, equipment, medicine, commodities and policy

Interaction between limbic circuits and basal ganglia in behaviour inhibition

Changing behaviour in response to changing internal and external situations is crucial for survival. In particular, we need to inhibit ongoing, unwanted or inappropriate behaviour. Behavioural inhibition includes inhibition of an ongoing action, thought or emotion (in the basal ganglia; BG). But it can also involve inhibition of goals (in the limbic system) – which is much slower. A better understanding of the neural mechanisms controlling inhibition of behaviour is important for cognitive neuroscience, particularly in relation to problems of impulsivity. This thesis aims to fill a gap in our understanding of behavioural inhibition and to elucidate the parallel circuits that control its different types. Several lesion, neuroimaging, and electrophysiological studies have been conducted to understand the role of brain regions in behavioural inhibition. Previous research has identified roles for the BG, orbitofrontal cortex (OFC) and hippocampus (HPC) in generation of various frequencies of rhythmicity during behavioural inhibition. However, the interaction between these regions has not been studied in rats during simple learning, simple action inhibition and complex behavioural inhibition. The stop signal task (SST) is the most commonly used paradigm to study simple behavioural inhibition. In this study, I recorded local field potentials (LFPs) simultaneously from BG (particularly striatum; STR and subthalamic nucleus; STN), OFC and HPC while rats performed the SST to assess how simple action inhibition differs from complex behavioural inhibition linked to goal-conflict. The data show increases in the STN LFP spectral beta power and coherence with OFC after stopping an ongoing action (simple stopping). In contrast, stop failure increased HPC-STN coherent activity in the theta frequency band. In addition to the HPC, goal-conflict also activates OFC and STN during high conflict at higher theta frequency (11-12 Hz). In contrast, the conflict induced coherence effect was seen at lower theta frequencies (5-8 Hz) between two pairs of STN (HPC-STN and OFC-STN). The results from the various experiments suggest that part of BG (STR and STN) and limbic system work in parallel and in a dynamic way for learning, response inhibition and complex behavioural inhibition (approach-avoidance conflict). The HPC is not involved in simple motor learning but may receive motivational information form STR and OFC. Simple inhibition involves mainly cortex and BG, while complex inhibition during goal-conflict also involves HPC, OFC and STN. Interestingly, goal inhibition appears to access circuits involved in simple stopping via OFC. In conclusion, functional connections between limbic and BG provides an adaptive control, so that goal selection (limbic structures) and programming of motor action (BG) can operate in parallel

Monthly distributions of children under five with pneumonia.

<p>Monthly distributions of children under five with pneumonia.</p

Age distributions of children under five with pneumonia.

<p>Age distributions of children under five with pneumonia.</p

Ethnic distributions of children under five with pneumonia.

<p>Ethnic distributions of children under five with pneumonia.</p

Proportion of total inpatient admissions of children under five for pneumonia.

*<p>Under five.</p

Ethnic codes as defined by the Health Management Information System.

<p>Ethnic codes as defined by the Health Management Information System.</p

Gender distribution of children under five with pneumonia.

<p>Gender distribution of children under five with pneumonia.</p