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Cazzanelli, S.

Publications and source records attributed to Cazzanelli, S..

3 recordsLinked to original sources

Temporal Patterns of Brain Network Plasticity During the Onset and Maintenance of Neuropathic Pain in Male Mice

Neuropathic pain arises from complex peripheral and central mechanisms and induces long-lasting maladaptive changes in the brain. To investigate the temporal dynamics of these changes, we examined resting-state functional connectivity (FC) in a mouse model of neuropathic pain across its initiation and maintenance phases. Using functional ultrasound imaging to capture whole-brain FC over disease progression, we conducted two complementary studies: a longitudinal assessment in anesthetized animals and an analysis of awake cohorts at distinct disease stages. Both exploratory and literature-guided analyses revealed that FC across most large-scale networks remained remarkably stable during pain maintenance. In contrast, pain onset was marked by enhanced FC between key regions involved in sensory, emotional, and motivational processing, including the motor cortex and nucleus accumbens, the prelimbic and insular cortices, and the infralimbic cortex and hypothalamus. As pain persisted, we observed reduced FC within the somatomotor network, reflecting functional disconnection. Additionally, postsurgical pain alone produced enduring FC changes within the prefrontal cortex, hippocampus, and insula, indicating long-term central plasticity independent of neuropathic injury. Together, these findings reveal dynamic, network-specific adaptations that distinguish the onset and maintenance phases of neuropathic pain and surgery-related plasticity.

neuroscience↗

Specific and non-uniform brain states during cold perception in mice

The quest to decode the complex supraspinal mechanisms that integrate cutaneous thermal information in the central system is still ongoing. The dorsal horn of the spinal cord is the first hub that encodes thermal input which is then transmitted to brain regions via the spinothalamic and thalamo-cortical pathways. So far, our knowledge about the strength of the interplay between the brain regions during thermal processing is limited. To address this question, we imaged the brains of awake and freely-moving mice using Functional Ultrasound imaging during plantar exposure to constant and varying temperatures. Our study, a synchronous large field investigation of mice brains reveals for the first time the brain states and the specific dynamic interplay between key regions involved in thermal processing. Our study reveals: i) a dichotomy in the response of the somato-motor-cingulate cortices and the hypothalamus, which was never described before, due to the lack of appropriate tools to study such regions with both good spatial and temporal resolutions. ii) We infer that cingulate areas may be involved in the affective responses to temperature changes. iii) Colder temperatures (ramped down) reinforces the disconnection between the somato-motor-cingulate and hypothalamus networks. iv) Finally, we also confirm the existence in the mouse brain of a dynamic brain mode characterized by low cognitive strength, described previously only in non-human primates and humans. The present study points towards the existence of a common hub between somato-motor and cingulate regions, whereas hypothalamus functions are related to a secondary network.

neuroscience↗

Functional convergence of autonomic and sensorimotor processing in the lateral cerebellum

The cerebellum is involved in control of voluntary and autonomic rhythmic behaviors, yet it is largely unclear to what extent it coordinates these in a concerted action. Here, we studied Purkinje cell activity during unperturbed and perturbed respiration in cerebellar lobules simplex, crus 1 and 2. During unperturbed (eupneic) respiration complex spike and simple spike activity encoded respiratory activity, the timing of which corresponded with ongoing sensorimotor feedback. Instead, upon whisker stimulation mice concomitantly accelerated their simple spike activity and inspiration in a phase-dependent manner. Moreover, the accelerating impact of whisker stimulation on respiration could be mimicked by optogenetic stimulation of Purkinje cells and prevented by cell-specific genetic modification of their AMPA receptors that hampered increases in simple spike firing. Thus, the impact of Purkinje cell activity on respiratory control is context- and phase-dependent, suggesting a coordinating role for the cerebellar hemispheres in aligning autonomic and sensorimotor behaviors.

neuroscience↗