Lind Lab

In the Lind lab, we investigate the mechanism behind healthy brain tissue and blood flow recruitment at a cellular level, focusing on the interaction of astrocytes and neurons during active sensing. Our experiments aim to expand the current understanding of the processes that procure sufficient nutrition to the tissue in the context of attention and sensory processing.

The research in the Lind lab focuses on how emotional context and attention to a task alter the cortical processing of sensory input (https://doi.org/10.1101/2024.04.16.589720). I work in awake mice and investigate the somatosensory response in the whisker barrel cortex. This sensory system is optimal for this investigation because the whisker deflections can be used as a visual cue for when sensory input flows via the thalamus to the cortex. The voluntary whisker movements reveal when the barrel cortex receives input. The dynamics involved in cortical excitation in the awake and freely behaving animal depend on the shifting activation of complex neuronal circuits and neuromodulator release patterns. Astrocytes are a cell type whose activity is acutely dependent on brain state. Proof of astrocytic modification at synapses has been building up. Besides the contribution to synaptic transmission, astrocytes are also involved in the neurovascular coupling that ensures sufficient oxygen and glucose delivery to activated neurons. Thus, we use the context of active sensing to investigate the astrocytic role in the brain-state-dependent processing of sensory input. Studies of astrocyte activity have evolved to reveal heterogeneity in signals with regard to both spatial and temporal distribution. This reflects the manifold mechanisms involving this glial cell, from homeostatic processes to neuroimmune responses and interactions with both excitatory and inhibitory neurons. The morphology of a healthy astrocytes allows for the detection of all kinds of neuronal activity within its domain. Very fast and localized astrocyte Ca²⁺ activity has been shown to occur where astrocytes associate tightly with synapses. To elucidate the astrocytic activity during natural behavior, experiments are done in awake mice, distinguishing between differing causes of localized brain activation and blood flow modulation. Imaging studies are combined with image processing techniques to exploit the spatial strength of the 2-photon fluorescence imaging technique. The identification of healthy astrocytic activity patterns in awake, naturally behaving mice is the basis for studying astrocyte reactivity in diseases. Reactive astrocytes are involved in the progression of most neurodegenerative diseases and several other CNS afflictions. Our experiments allow for real-time in vivo investigations of astrocyte and vascular involvement in disease progression at the cellular level.