Neural assemblies

…synaptic wiring of strongly connected neural populations, known as neural assemblies. However, experimental evidence for assembly formation has been limited to inferring changes in synaptic connectivity from changes in neural activity following behavioral learning. Using tagged c-fos activity combined with channelrhodopsin expression, we directly measured the synaptic strength between neurons in the Piriform cortex (PCx) following mice learning an odor discrimination task. Our results suggest that an assembly forms after learning, but

…network model, to show how hippocampal neural assemblies may evolve differently, depending on the frequency of presentation of the stimuli (Boscaglia et al., 2023). Specifically, we built a dynamic attractor network model starting from a standard rate attractor model to which we added an online Hebbian learning

Long-term recordings in patients and animal models reveal circadian and multidien (multiple days) rhythmicity in epilepsy. The underlying mechanisms of these cycles are not known. We are interested in predicting the onset of epileptic seizures over the scale of days. To this end, we performed chronic telemetric and single-unit recordings in epileptic rats (pilocarpine model). The primary focus of our investigation lies in the study of large network discharges known as interictal spikes (IS), closely associated with epileptic seizures.As previously shown, in our recordings the number of seizure

The connectivity structure of many biological systems, including neural circuits, is highly non-uniform. Recent technologies allow detailed mapping of these irregularities, but our understanding of their effect on the overall circuit dynamics is still lacking. By developing complex system analytical tools that perform reduction of the network, I determine the impact of connectivity features on network dynamics. I will demonstrate the use of these tools on neural assemblies (clusters), a ubiquitous non-uniform structure in our brains. I will show how neural assemblies of different sizes natural

…The process models the formation of neural assemblies, a longstanding proposal for the representation of abstract concepts in the brain. It is applied to a directed graph as follows: in each iteration, a subset of $k$ vertices of the graph are identified as winners; the next round winners are the vertices that have the highest total degree from the current winners, with ties broken randomly. Previous theoretical analyses of neural assemblies model the connectome as a directed Erd\"

Behavioral states in humans and animals vary over time, and these shifts alter cortical processing and cognitive function. For example, one striking result is an observed inverted-U relationship between arousal and performance on signal detection tasks. However, there is currently a need for mechanistic models that can explain these state-dependent effects. Here we address this challenge in the context of arousal-dependent auditory processing in rodents. In experiments where mice were presented tones of different frequencies, we found that frequency information could be best decoded from popu