Sung-Ho Lee

2 papers in the library · publishing 2022

Papers

Chemogenetic stimulation of tonic locus coeruleus activity strengthens the default mode network

Science Advances April 1, 2022 E. Oyarzabal, Li-Ming Hsu, Manasmita Das et al.

Activating norepinephrine-releasing neurons in the locus coeruleus (LC) of the mouse brain alters the default mode network (DMN). Chemogenetic stimulation of these neurons decreased cerebral blood volume and glucose uptake while increasing synchronous low-frequency fMRI activity in the frontal cortices of the DMN. Fiber photometry confirmed that LC-NE activation triggered norepinephrine release, enhanced calcium-weighted neuronal spiking, and reduced cerebral blood volume in the anterior cingulate cortex. These findings indicate that LC-NE changes the typical relationship between neuronal activity and blood volume in the frontal DMN. The activation also strengthened functional connectivity within the frontal DMN, an effect mediated by reduced inputs from retrosplenial and hippocampal regions.

DOI: 10.1126/sciadv.abm9898 Full text Medicine Biology

Optogenetic stimulation of anterior insular cortex neurons reveals causal mechanisms underlying suppression of the default mode network by the salience network

Vinod Menon, Domenic Cerri, Byeongwook Lee et al. preprint

Stimulating neurons in the anterior insular cortex of rats suppresses activity in the default mode network and reduces functional connectivity between the salience network and default mode network, as well as within the default mode network itself. The findings demonstrate a causal role for anterior insular cortex neurons in dynamically suppressing and decoupling the default mode network, revealing previously unknown features of rodent brain network organization and advancing understanding of cross-network interactions and brain network switching.

DOI: 10.1101/2022.06.06.495040