Topic: 2-photon microscopy

In natural environments, animals must decide when to commit to one option, such as searching for food, or switching to another option, such as escaping a predator. How the nervous system mediates this “stay/switch” decision-making process during naturalistic behavior remains largely unknown. Here, we study stay/switch decisions in fruit flies by presenting optogenetically-driven heat pulses during courtship of a female. We developed a closed-loop stimulation paradigm in which the male receives optogenetic stimulation conditioned on his real-time song production. In response to the stimulus, fl

Experimental work across a variety of species has demonstrated that spontaneously generated behaviors are robustly correlated to variation in neural activity within the cerebral cortex. Indeed, functional magnetic resonance imaging (fMRI) data suggest that functional connectivity in cortical networks varies across distinct behavioral states, providing for the dynamic reorganization of patterned activity. However, these studies generally lack the temporal resolution to establish links between cortical signals and the continuously varying fluctuations in spontaneous behavior typically observed i

Oligodendrocyte precursor cells (OPCs) serve as progenitors for oligodendrocytes (OLs) throughout their life, contributing to developmental and adaptive myelination, as well as myelin repair. OPCs are known to make synaptic and extra-synaptic contacts with axons, but the mechanisms by which they integrate the information relayed by the neuronal activity into Ca2+ signals, which in turn influence their fate and survival, are still unclear. Using newly developed transgenic mouse lines to express genetically encoded Ca2+ sensors in OPCs, we performed 2-photon microscopy in the somatosensory corte

Sensorimotor adaptation, crucial for refining movements in response to unexpected errors, fundamentally depends on the cerebellum. The olivary climbing fiber (CF) input to cerebellar Purkinje cells (PC) acts as a “teacher” signal during motor learning and drives cerebellar plasticity. Although the CF input reliably evokes PC dendritic spikes, it is not the only signal that modulates this post-synaptic response. To disentangle the modulation of the pre-synaptic CF burst from that of its post-synaptic PC dendritic response, we simultaneously imaged PC dendrites and CF terminals with 2-photon mic

X-chromosome inactivation (XCI) is an epigenetic process unique to female mammals, and creates a mosaic of cells expressing either the maternal or paternal X-chromosome. Females heterozygous for genes leading to X-linked neurodevelopmental disorders (NDD) exhibit a variety of phenotypes. We hypothesize that variability in the ratio and location of cells expressing the mutant vs wild type (WT) X-chromosome is an underlying cause of phenotypic variability. To investigate this hypothesis, we studied oligodendrocyte (OL) development and myelination in Fragile X syndrome (FXS), a NDD caused by the

The frontal cortex plays critical roles in learning and decision-making, particularly in representing reward-related variables such as reward magnitude and probability. Previous studies have identified frontal neural representations of these variables in expertly trained animals. However, it remains unknown how these representations emerge during learning from naive to expert. To address this gap, we use 2-photon microscopy to longitudinally record the activity of the same population of neurons in the dorsomedial frontal cortex. We record from head-fixed mice learning to perform Pavlovian or o

Despite the axolotl’s exceptional ability to regenerate complex tissues, little research has focused on this phenomenon in the brain. We aim to understand whether a morphological repair observed during axolotl brain regeneration is accompanied by a functional restoration of neuronal circuits. To do so, we are establishing state-of-the-art neuroscience tools in our model system, namely GCaMP imaging of neuronal activity, behavioral assays and optogenetic stimulation. Using these methods, we will investigate the visuomotor circuit of the axolotl in intact, injured and regenerating conditions.Rec

Synapse loss is a key feature of many neurodegenerative diseases involving cognitive deficits, and is also the strongest correlate of cognitive decline in Alzheimer’s disease (AD). In addition, the integrity of dendritic spines, the post-synaptic sites of excitatory synapses, have been shown to play a key role in cognitive resilience against AD. Given the critical role of synaptic loss in cognitive decline, we hypothesized that synaptic compensation and repair play a vital role in counteracting synapse loss and as a consequence, in delaying the onset of cognitive deficits. The aim of our study