Ongoing habenular activity is driven by forebrain networks and modulated by olfactory stimuli

Abstract

Ongoing neural activity, which represents internal brain states, is constantly modulated by the sensory information that is generated by the environment. In this study, we show that the habenular circuits act as a major brain hub integrating the structured ongoing activity of the limbic forebrain circuitry and the olfactory information. We demonstrate that ancestral homologs of amygdala and hippocampus in zebrafish forebrain are the major drivers of ongoing habenular activity. We also reveal that odor stimuli can modulate the activity of specific habenular neurons that are driven by this forebrain circuitry. Our results highlight a major role for the olfactory system in regulating the ongoing activity of the habenula and the forebrain, thereby altering brain's internal states.

Epigenetically distinct synaptic architecture in clonal compartments in the teleostean dorsal pallium

“…Here, it should be noted that our axonal projection analysis might have missed the projections from mature neurons, because the HuC promoter labels preferentially neural progenitors and disappears at later stages 19 . Thus, brain-wide exhaustive connectome analysis by electron microscopy 42 or neurophysiological analysis will be necessary for further study 43 .…”

Not so spontaneous: Multi-dimensional representations of behaviors and context in sensory areas

“…This activity is observed in many species, from fish to rodents to humans (Fox et al, 2005;Mohajerani et al, 2013;Romano et al, 2015) and in both developing and mature animals. Spontaneous patterns of neural activity are highly structured across neurons and in time (Bartoszek et al, 2021;Clancy et al, 2019;Han et al, 2008;Kenet et al, 2003;Luczak et al, 2009;Miller et al, 2014;see Box 3). These structured neural patterns often also appear during the presentation of sensory stimuli, suggesting that these patterns may interact with sensory processing (Chen et al, 2006).…”

Dynamics and Potential Significance of Spontaneous Activity in the Habenula

“…This was demonstrated in rats using electrical recordings of brain slices, and has also been found in the zebrafish, using two-photon calcium imaging of tethered animals (Jetti et al, 2014;Fore et al, 2018), or CaMPARI-based labelling of freely swimming fish (Fosque et al, 2015). This activity is driven by input from the forebrain (Bartoszek et al, 2021).…”