Topic: Neuropixels 2.0

Sensory neuron responses vary across repeated presentations of the same stimuli, but whether this trial-to-trial variability represents noise versus unidentified signals remains unresolved (1–3). Some of the variability can be attributed to correlations of neural activity with locomotion, arousal, and other overt movements (4–7). We hypothesized that distributed brain states, i.e., patterns of neural activity observable in other brain regions, may account for more of the unexplained trial-to-trial variability in responses of sensory cortical neurons. To test this, we used Neuropixels 2.0 probe

Spontaneous neural fluctuations and traveling waves are often observed in large scale population activity in diverse brain areas and in various brain states (Lubenov et al. 2009; Muller et al. 2016; Hamid et al. 2021). Spatiotemporal dynamics of neural activity, including traveling waves, likely implement diverse computations, including motor planning, decision making, and memory consolidation (Ermentrout & Kleinfeld 2001; Muller et al 2018). However, the detailed spatiotemporal patterns of wave propagation have not been well characterized in awake mammals. Critically, it is still largely

Perceptual decision-making is crucial for survival, requiring the integration of dynamic sensory evidence from the environment with internal state variables (e.g. context, priors, value) to choose an appropriate action plan. Neural correlates of perceptual decisions are more distributed than once thought, having been found within the cortex, striatum, and superior colliculus (SC). Recent work has suggested a potentially novel node in this network - the midbrain reticular nucleus (MRN) - which was one of the few regions that encoded visual and action selection signals in a brain-wide survey of

The entorhinal cortex is a crucial hub for the coding of animals’ experiences in space. Grid cells, key components of this network, exhibit multiple firing fields that tessellate the environment as a function of the animals’ location. At the population level, the dynamics of the grid cell network reside on a toroidal manifold, irrespective of the sensory inputs or behavioral state, in agreement with continuous attractor networks (CAN) theories.However, the developmental origin of toroidal topology remains to be determined. Using Neuropixels 2.0 we obtained high-density population recordings in

The hippocampal-entorhinal circuit is part of a network of areas involved in the encoding and retrieval of representations of distinct spatial environments and episodes. We explored the complexity of neural activity patterns (‘dimensionality’), to understand how multiple maps are maintained in sub-populations of neurons. High dimensionality suggests unique neural 'maps' for different environments, while low dimensionality indicates overlapping representations across episodes. Prior research has shown distinct spatial representations in hippocampal subfields CA1/ CA3, with increased dimensional

Neuronal ensembles that hold specific memories (memory engrams), are defined as enduring physical and/or chemical change in a neural network that is the result of neuronal activation by episodic stimuli [1] Engram cells have been identified in multiple brain regions, including the hippocampus, amygdala, thalamus, and cortex It has been hypothesized that these distributed engrams are functionally connected [2] This neural network can be specifically reactivated, resulting in the recall of the original memory [3]However, how the interaction among multiple regions facilitates the consolidation, o