alessana

• Ferro, Mattia; Lamanna, Jacopo; Ripamonti, Maddalena; Racchetti, Gabriella; Arena, Alessandro; Spadini, Sara; Montesano, Giovanni; Cortese, Riccardo; Zimarino, Vincenzo & Malgaroli, Antonio (2017). Functional mapping of brain synapses by the enriching activity-marker SynaptoZip. Nature Communications.  ISSN 2041-1723. 8(1). doi: 10.1038/s41467-017-01335-4
• Arena, Alessandro; Lamanna Jacopo; Gemma Marco; Ripamonti Maddalena; Ravasio Giuliano; Zimarino Vincenzo; De Vitis Assunta; Beretta Luigi & Malgaroli Antonio (2016). Linear transformation of the encoding mechanism for light-intensity underlies the paradoxical enhancement of cortical visual responses by sevoflurane. The Journal of Physiology. 595(1). doi: 10.1113/JP272215
• Montesano, Giovanni; Belfiore, Marcello; Ripamonti, Maddalena; Arena, Alessandro; Lamanna, Jacopo; Ferro, Mattia; Zimarino, Vincenzo; Ambrosi, Alessandro & Malgaroli Antonio (2015). Effects of the Concomitant Activation of ON and OFF Retinal Ganglion Cells on the Visual Thalamus: Evidence for an Enhanced Recruitment of GABAergic Cells. Frontiers in Neural Circuits. 9. doi: 10.3389/fncir.2015.00077

• Arena, Alessandro; Juel, Bjørn Erik; Comolatti, Renzo; Thon, Sarah & Storm, Johan Frederik (2022). Capacity for consciousness under ketamine anaesthesia is selectively associated with activity in posteromedial cortex in rats. Neuroscience of Consciousness. ISSN 2057-2107. 2022(1), p. 1–15. doi: 10.1093/nc/niac004. Full text in Research Archive Show summary

  It remains unclear how specific cortical regions contribute to the brain’s overall capacity for consciousness. Clarifying this could help distinguish between theories of consciousness. Here, we investigate the association between markers of regionally specific (de)activation and the brain’s overall capacity for consciousness. We recorded electroencephalographic responses to cortical electrical stimulation in six rats and computed Perturbational Complexity Index state-transition (PCIST), which has been extensively validated as an index of the capacity for consciousness in humans. We also estimated the balance between activation and inhibition of specific cortical areas with the ratio between high and low frequency power from spontaneous electroencephalographic activity at each electrode. We repeated these measurements during wakefulness, and during two levels of ketamine anaesthesia: with the minimal dose needed to induce behavioural unresponsiveness and twice this dose. We found that PCIST was only slightly reduced from wakefulness to light ketamine anaesthesia, but dropped significantly with deeper anaesthesia. The high-dose effect was selectively associated with reduced high frequency/low frequency ratio in the posteromedial cortex, which strongly correlated with PCIST. Conversely, behavioural unresponsiveness induced by light ketamine anaesthesia was associated with similar spectral changes in frontal, but not posterior cortical regions. Thus, activity in the posteromedial cortex correlates with the capacity for consciousness, as assessed by PCIST, during different depths of ketamine anaesthesia, in rats, independently of behaviour. These results are discussed in relation to different theories of consciousness.

• Arena, Alessandro; Juel, Bjørn Erik; Comolatti, Renzo; Thon, Sarah Kriebel & Storm, Johan (2021). Does the posteromedial cortex play a primary role for the capacity for consciousness in rats? bioRxiv. ISSN 2692-8205. doi: 10.1101/2021.01.22.427747. Show summary

  It remains unclear how specific cortical regions contribute to the brain’s overall capacity for consciousness. Clarifying this could help distinguish between theories of consciousness. Here, we investigate the association between markers of regionally specific (de)activation and the brain’s overall capacity for consciousness. We recorded electroencephalographic (EEG) responses to cortical electrical stimulation in 6 rats, and computed Perturbational Complexity Index state-transition (PCIST), which has been extensively validated as an index of the capacity for consciousness in humans. We also estimated the balance between activation and inhibition of specific cortical areas with the ratio between high and low frequency power (HF/LF) from spontaneous EEG activity at each electrode. We repeated these measurements during wakefulness, and under the influence of ketamine anaesthesia at two doses: the minimal dose needed to induce behavioural unresponsiveness and twice this dose. We found that PCIST was only slightly reduced from wakefulness to light ketamine anaesthesia, but dropped significantly down with deeper anaesthesia. The high-dose effect was selectively associated with reduced HF/LF ratio in the posteromedial cortex, which strongly correlated with PCIST. Conversely, behavioural unresponsiveness induced by light ketamine anaesthesia, was associated with similar spectral changes in frontal, but not posterior cortical regions. These findings seem to support the claim that the posteromedial cortex may play a primary role for the capacity for consciousness. Such region-specific associations between cortical activation and the overall capacity for consciousness must be accounted for by theories of consciousness.

• Arena, Alessandro; Comolatti, Renzo; Thon, Sarah Kriebel; Casali, Adenauer G. & Storm, Johan Frederik (2021). General Anesthesia Disrupts Complex Cortical Dynamics in Response to Intracranial Electrical Stimulation in Rats. eNeuro. ISSN 2373-2822. 8(4). doi: 10.1523/ENEURO.0343-20.2021. Full text in Research Archive
• Arena, Alessandro; Thon, Sarah; Casali, Adenauer Girardi & Storm, Johan Frederik (2020). General anaesthesia disrupts complex cortical dynamics in response to intracranial electrical stimulation in rats. BioRxiv. ISSN 0362-4331. doi: 10.1101/2020.02.25.964056.
• Ferro, Mattia; Lamanna, Jacopo; Ripamonti, Maddalena; Racchetti, Gabriella; Arena, Alessandro & Spadini, Sara [Show all 10 contributors for this article] (2017). Functional mapping of brain synapses by the enriching activity-marker SynaptoZip. Nature Communications. ISSN 2041-1723. 8(1). doi: 10.1038/s41467-017-01335-4. Full text in Research Archive

View all works in Cristin

• Arena, Alessandro; Comolatti, Renzo; Casali, Adenauer G. & Storm, Johan F. (2018). Cortical complexity and cause‐effect power are reduced by general anesthesia compared to wakefulness in rats.
• Pigorini, Andrea; Arena, Alessandro; Barbero Castillo, A.; Wolff, A.; Galluzzi, A. & Raimondo, F. [Show all 18 contributors for this article] (2018). Consciousness and brain complexity: a multi-scale exploration across species and model .
• Arena, Alessandro; Comolatti, Renzo; Casali, Adenauer G. & Storm, Johan F. (2018). A New Approach For Assessing Perturbational Complexity In Rats.
• Arena, Alessandro (2018). Conscious vs. unconscious brain states in rodents.
• Nilsen, Andre Sevenius; Arena, Alessandro; Juel, Bjørn Erik; Storm, Johan Frederik; Murphy, Ricardo & Hu, Hua [Show all 7 contributors for this article] (2017). Forsknigstorget: Hvordan kan hjernen skape bevissthet.
• Arena, Alessandro (2017). Toward exploration of cortical complexity in rats.
• Arena, Alessandro & Storm, Johan Frederik (2017). TOWARD THE EXPLORATION OF COMPLEXITY IN RATS.

View all works in Cristin