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NeuroImage Feb 2020Following a first version AAL of the automated anatomical labeling atlas (Tzourio-Mazoyer et al., 2002), a second version (AAL2) (Rolls et al., 2015) was developed...
Following a first version AAL of the automated anatomical labeling atlas (Tzourio-Mazoyer et al., 2002), a second version (AAL2) (Rolls et al., 2015) was developed that provided an alternative parcellation of the orbitofrontal cortex following the description provided by Chiavaras, Petrides, and colleagues. We now provide a third version, AAL3, which adds a number of brain areas not previously defined, but of interest in many neuroimaging investigations. The 26 new areas in the third version are subdivision of the anterior cingulate cortex into subgenual, pregenual and supracallosal parts; subdivision of the thalamus into 15 parts; the nucleus accumbens, substantia nigra, ventral tegmental area, red nucleus, locus coeruleus, and raphe nuclei. The new atlas is available as a toolbox for SPM, and can be used with MRIcron.
Topics: Atlases as Topic; Brain; Humans; Image Interpretation, Computer-Assisted; Neuroimaging
PubMed: 31521825
DOI: 10.1016/j.neuroimage.2019.116189 -
Experimental Physiology Nov 2019What is the topic of this review? Rubral modulation of pontomedullary respiratory rhythm and pattern generating circuitry powerfully contributes to regulation of... (Review)
Review
NEW FINDINGS
What is the topic of this review? Rubral modulation of pontomedullary respiratory rhythm and pattern generating circuitry powerfully contributes to regulation of breathing. What advances does it highlight? Studies have demonstrated extensive rubromedullary and rubrospinal projections to zones generating and organizing the respiratory rhythm and pattern. Rubral modulation of respiratory output effects inspiratory expiratory phase transitions with stimulation generating inhibitory or excitatory responses of medullary inspiratory and expiratory units. The red nucleus mediates hypoxic ventilatory depression, integrates respiratory output with oromotor and locomotor activity, and modulates respiratory output during noxious stimulation.
ABSTRACT
Although normal triphasic eupnoea can be produced by the pontomedullary respiratory network after pontomesencephalic transection, the midbrain provides important modulation of respiration. Specifically, stimulation of the red nucleus elicits inspiratory inhibition, as manifest in the phrenic neurogram, in addition to excitation and inhibition of individual medullary respiratory-related units, with the majority of premotor units that receive rubral modulation being inhibited. Stimulation of the red nucleus also induces respiratory phase transitions, which appear to be pontine independent. These effects might be mediated by rubrobulbar and/or rubrospinal tracts. Although lesioning of the red nucleus does not alter respiration in normoxic conditions, it eliminates hypoxic ventilatory depression, which is the second phase of the biphasic ventilatory response to low oxygen tension. The finding that the red nucleus also plays a role in anti-nociception suggests that it might coordinate respiratory responses during noxious stimulation and, given that the red nucleus regulates upper limb flexors, it might represent one region in a distributed bulbar network contributing to respiratory-locomotor integration. Modulation of jaw opening by the red nucleus would support a model whereby it coordinates oromotor activity with breathing. Thus, the multiplicity of roles played by the red nucleus aptly position it to coordinate respiration in a variety of behavioural states. In this review, we seek to highlight the different features and regional specializations of the rubral contribution to respiratory control and underscore its vital importance to breathing in the freely behaving mammal.
Topics: Animals; Exhalation; Locomotion; Medulla Oblongata; Phrenic Nerve; Respiration; Respiratory Center
PubMed: 31408227
DOI: 10.1113/EP087720 -
Brain Structure & Function Jan 2021The red nucleus (RN) is a large subcortical structure located in the ventral midbrain. Although it originated as a primitive relay between the cerebellum and the spinal... (Review)
Review
The red nucleus (RN) is a large subcortical structure located in the ventral midbrain. Although it originated as a primitive relay between the cerebellum and the spinal cord, during its phylogenesis the RN shows a progressive segregation between a magnocellular part, involved in the rubrospinal system, and a parvocellular part, involved in the olivocerebellar system. Despite exhibiting distinct evolutionary trajectories, these two regions are strictly tied together and play a prominent role in motor and non-motor behavior in different animal species. However, little is known about their function in the human brain. This lack of knowledge may have been conditioned both by the notable differences between human and non-human RN and by inherent difficulties in studying this structure directly in the human brain, leading to a general decrease of interest in the last decades. In the present review, we identify the crucial issues in the current knowledge and summarize the results of several decades of research about the RN, ranging from animal models to human diseases. Connecting the dots between morphology, experimental physiology and neuroimaging, we try to draw a comprehensive overview on RN functional anatomy and bridge the gap between basic and translational research.
Topics: Brain Mapping; Humans; Neuroimaging; Red Nucleus
PubMed: 33180142
DOI: 10.1007/s00429-020-02171-x -
Nature Communications Oct 2023Previous studies have speculated that brain activity directly controls immune responses in lymphoid organs. However, the upstream brain regions that control lymphoid...
Previous studies have speculated that brain activity directly controls immune responses in lymphoid organs. However, the upstream brain regions that control lymphoid organs and how they interface with lymphoid organs to produce stress-induced anxiety-like behavior remain elusive. Using stressed human participants and rat models, we show that CCL5 levels are increased in stressed individuals compared to controls. Stress-inducible CCL5 is mainly produced from cervical lymph nodes (CLN). Retrograde tracing from CLN identifies glutamatergic neurons in the red nucleus (RN), the activities of which are tightly correlated with CCL5 levels and anxiety-like behavior in male rats. Ablation or chemogenetic inhibition of RN glutamatergic neurons increases anxiety levels and CCL5 expression in the serum and CLNs, whereas pharmacogenetic activation of these neurons reduces anxiety levels and CCL5 synthesis after restraint stress exposure. Chemogenetic inhibition of the projection from primary motor cortex to RN elicits anxiety-like behavior and CCL5 synthesis. This brain-lymph node axis provides insights into lymph node tissue as a stress-responsive endocrine organ.
Topics: Rats; Humans; Male; Animals; Red Nucleus; Stress, Psychological; Anxiety; Lymph Nodes; Brain; Chemokine CCL5
PubMed: 37903803
DOI: 10.1038/s41467-023-42814-1 -
Science Advances Sep 2022Physical exercise is rewarding and protective against drug abuse and addiction. However, the neural mechanisms underlying these actions remain unclear. Here, we report...
Physical exercise is rewarding and protective against drug abuse and addiction. However, the neural mechanisms underlying these actions remain unclear. Here, we report that long-term wheel-running produced a more robust increase in c-fos expression in the red nucleus (RN) than in other brain regions. Anatomic and functional assays demonstrated that most RN magnocellular portion (RNm) neurons are glutamatergic. Wheel-running activates a subset of RNm glutamate neurons that project to ventral tegmental area (VTA) dopamine neurons. Optogenetic stimulation of this pathway was rewarding, as assessed by intracranial self-stimulation and conditioned place preference, whereas optical inhibition blocked wheel-running behavior. Running wheel access decreased cocaine self-administration and cocaine seeking during extinction. Last, optogenetic stimulation of the RNm-to-VTA glutamate pathway inhibited responding to cocaine. Together, these findings indicate that physical exercise activates a specific RNm-to-VTA glutamatergic pathway, producing exercise reward and reducing cocaine intake.
PubMed: 36054363
DOI: 10.1126/sciadv.abo1440 -
Frontiers in Behavioral Neuroscience 2022For almost a century the classical conditioning of nictitating membrane/eyelid responses has been used as an excellent and feasible experimental model to study how the... (Review)
Review
For almost a century the classical conditioning of nictitating membrane/eyelid responses has been used as an excellent and feasible experimental model to study how the brain organizes the acquisition, storage, and retrieval of new motor abilities in alert behaving mammals, including humans. Lesional, pharmacological, and electrophysiological approaches, and more recently, genetically manipulated animals have shown the involvement of numerous brain areas in this apparently simple example of associative learning. In this regard, the cerebellum (both cortex and nuclei) has received particular attention as a putative site for the acquisition and storage of eyelid conditioned responses, a proposal not fully accepted by all researchers. Indeed, the acquisition of this type of learning implies the activation of many neural processes dealing with the sensorimotor integration and the kinematics of the acquired ability, as well as with the attentional and cognitive aspects also involved in this process. Here, we address specifically the functional roles of three brain structures (red nucleus, cerebellar interpositus nucleus, and motor cortex) mainly involved in the acquisition and performance of eyelid conditioned responses and three other brain structures (hippocampus, medial prefrontal cortex, and claustrum) related to non-motor aspects of the acquisition process. The main conclusion is that the acquisition of this motor ability results from the contribution of many cortical and subcortical brain structures each one involved in specific (motor and cognitive) aspects of the learning process.
PubMed: 36570703
DOI: 10.3389/fnbeh.2022.1057251 -
The Journal of Neuroscience : the... Jun 2020The ability to adjust behavior is an essential component of cognitive control. Much is known about frontal and striatal processes that support cognitive control, but few...
The ability to adjust behavior is an essential component of cognitive control. Much is known about frontal and striatal processes that support cognitive control, but few studies have investigated how motor signals change during reactive and proactive adjustments in motor output. To address this, we characterized neural signals in red nucleus (RN), a brain region linked to motor control, as male and female rats performed a novel variant of the stop-signal task. We found that activity in RN represented the direction of movement and was strongly correlated with movement speed. Additionally, we found that directional movement signals were amplified on STOP trials before completion of the response and that the strength of RN signals was modulated when rats exhibited cognitive control. These results provide the first evidence that neural signals in RN integrate cognitive control signals to reshape motor outcomes reactively within trials and proactivity across them. Healthy human behavior requires the suppression or inhibition of errant or maladaptive motor responses, often called cognitive control. While much is known about how frontal brain regions facilitate cognitive control, less is known about how motor regions respond to rapid and unexpected changes in action selection. To address this, we recorded from neurons in the red nucleus, a motor region thought to be important for initiating movement in rats performing a cognitive control task. We show that red nucleus tracks motor plans and that selectivity was modulated on trials that required shifting from one motor response to another. Collectively, these findings suggest that red nucleus contributes to modulating motor behavior during cognitive control.
Topics: Animals; Behavior, Animal; Cognition; Executive Function; Female; Inhibition, Psychological; Male; Movement; Neurons; Psychomotor Performance; Rats; Rats, Long-Evans; Red Nucleus
PubMed: 32376779
DOI: 10.1523/JNEUROSCI.2775-19.2020