Biology subjects

Gallagher, N. M.

Publications and source records attributed to Gallagher, N. M..

3 recordsLinked to original sources

bioRxiv2024

A widespread electrical brain network encodes anxiety in health and depressive states

In rodents, anxiety is characterized by heightened vigilance during low-threat and uncertain situations. Though activity in the frontal cortex and limbic system is fundamental to supporting this internal state, the underlying network architecture that integrates activity across brain regions to encode anxiety across animals and paradigms remains unclear. Here, we utilize parallel electrical recordings in freely behaving mice, multiple translational paradigms known to induce anxiety, and machine learning to discover a multi-region network that encodes the anxious brain state. The network is composed of circuits widely implicated in anxiety behavior, it generalizes across many behavioral contexts that induce anxiety, and it fails to encode multiple behavioral contexts that do not. Strikingly, the activity of this network is also principally altered in two mouse models of depression. Thus, we establish a network-level process whereby the brain encodes anxiety in health and disease.

neuroscience↗

bioRxiv2022

Brain-wide oscillatory network selectively encodes aggression

Aggression is a psychological state characterized by intent to harm oneself or others, and often manifests as hostile, harmful, or violent action. Social aggression can aid an organism in securing access to resources1,2, or it can impair group function and survival in behavioral pathology3-5. Since many brain regions contribute to multiple social behaviors6-8, expanded knowledge of how the brain distinguishes between social states would enable the development of interventions that suppress violent action, while leaving other social behaviors intact. Here we showed that a murine aggressive internal state is encoded by a widespread network. This network is organized by prominent and synchronized theta (4-11 Hz) and beta (14-30 Hz) oscillations that relay through the medial prefrontal cortex, and couples to widespread cellular firing. Strikingly, network activity during social isolation was found to encode the trait aggressiveness of mice, and causal cellular manipulations known to impact aggression were found to modulate the networks activity. We next established that this network mediates aggression using closed-loop stimulation of medial prefrontal cortex and causal mediation analysis. Finally, we deployed Long-term integration of Circuits using connexins (LinCx) to selectively edit a key circuit within the network from the medial prefrontal cortex to nucleus accumbens. Editing this circuit chronically suppressed violent action while leaving non-aggressive social behavior intact.

neuroscience↗

bioRxiv2020

Brain-wide electrical dynamics encode an appetitive socioemotional state

Many cortical and subcortical regions contribute to complex social behavior; nevertheless, the network level architecture whereby the brain integrates this information to encode appetitive socioemotional behavior remains unknown. Here we measure electrical activity from eight brain regions as mice engage in a social preference assay. We then use machine learning to discover an explainable brain network that encodes the extent to which mice chose to engage another mouse. This socioemotional network is organized by theta oscillations leading from prelimbic cortex and amygdala that converge on ventral tegmental area, and network activity is synchronized with brain-wide cellular firing. The network generalizes, on a mouse-by-mouse basis, to encode socioemotional behaviors in healthy animals, but fails to encode an appetitive socioemotional state in a high confidence genetic mouse model of autism. Thus, our findings reveal the architecture whereby the brain integrates spatially distributed activity across timescales to encode an appetitive socioemotional brain state in health and disease.

neuroscience↗