About this Research Topic
External stimuli reaching the brain from peripheral sensory organs convey many variables collected from the environment, such as frequency and color. The brain must constantly discriminate between these sensory inputs and assign them to selected groups of cells. These extracted attributes must then be conveyed by neurons which will fire at maximal rate if the object’s characteristics suit the cell’s preference. For instance, in primary sensory cortices, neurons are optimally sensitive to specific features such as object orientation or auditory frequencies.
However, the target object is reconstructed by the sum of firing neurons activated by the entirety of object features. This neuronal reconstitution begins in primary sensory areas, each committed to one specific sensory modality. However, our environments are highly stimulating and dynamic, and understanding how the brain encodes rapidly changing sensory inputs remains an intriguing challenge. Several hypotheses have been put forward. For instance, firing rates have often been associated with stimulus strength. Other relationships with an object’s characteristics have been revealed such as intervals between spikes and latencies. It became recently possible to capture the spiking behavior of many cells simultaneously, discovering that neurons may fire in an oscillatory fashion that disperses from the original site of activity to other, remote cortical areas.
In particular, neuron clusters fire in synchrony at specific rhythms of oscillations. This rhythmic activity arises in a functionally circumscribed cortical area receiving a specific sensory input. These oscillations may spread to large and remote areas, sometimes overrunning an entire hemisphere, suggesting extensive functional links. However, dissociating nuances in frequency variation, or between features of a composite stimulus may be challenging to differentiate by strict rhythmicity of an ensemble of cells, even if the oscillations coincide with bursts of action potentials.
Technological progress offers alternative methods to study neuronal encoding processes. Recording simultaneously from many cells allows us to study cross-correlograms and disclose functional relationships between recorded cells. This technology leads to awareness of ensembles of connected cells; these linked cells are called connectomes or assemblies, and they are found in response to applied stimuli. Furthermore, we can associate or dissociate specific neurons with a connectome when a stimulus is modified. Consequently, functional coupling between cells is associated with specific characteristics of the presented targets. Thus, the constitution of the connectome (that is, the number of cells, their placement in the brain, their sensory selectivity) is determined by the nature of a particular stimulus.
To respond to rapidly changing stimuli, the connectome may change on the same time scale (within milliseconds). Some cells may join the connectome by strengthening their coupling, while other units may leave the group by weakening their links. Thus, the connectome is a functional unit of sorts, reflecting the characteristics of the applied stimulus.
The aim of this Research Topic is to explore the brain’s strategy to encode the immense variety of sensory inputs, often presented simultaneously. This encoding process must be accomplished with high precision in space and time domains.
We welcome all original research, review articles, methods, and data reports, on topics that include, but are not limited to:
1. Cellular responses, including neurochemical and electrophysiological
2. Synaptic transmission and circuits functions
3. Perception reactions
However, the target object is reconstructed by the sum of firing neurons activated by the entirety of object features. This neuronal reconstitution begins in primary sensory areas, each committed to one specific sensory modality. However, our environments are highly stimulating and dynamic, and understanding how the brain encodes rapidly changing sensory inputs remains an intriguing challenge. Several hypotheses have been put forward. For instance, firing rates have often been associated with stimulus strength. Other relationships with an object’s characteristics have been revealed such as intervals between spikes and latencies. It became recently possible to capture the spiking behavior of many cells simultaneously, discovering that neurons may fire in an oscillatory fashion that disperses from the original site of activity to other, remote cortical areas.
In particular, neuron clusters fire in synchrony at specific rhythms of oscillations. This rhythmic activity arises in a functionally circumscribed cortical area receiving a specific sensory input. These oscillations may spread to large and remote areas, sometimes overrunning an entire hemisphere, suggesting extensive functional links. However, dissociating nuances in frequency variation, or between features of a composite stimulus may be challenging to differentiate by strict rhythmicity of an ensemble of cells, even if the oscillations coincide with bursts of action potentials.
Technological progress offers alternative methods to study neuronal encoding processes. Recording simultaneously from many cells allows us to study cross-correlograms and disclose functional relationships between recorded cells. This technology leads to awareness of ensembles of connected cells; these linked cells are called connectomes or assemblies, and they are found in response to applied stimuli. Furthermore, we can associate or dissociate specific neurons with a connectome when a stimulus is modified. Consequently, functional coupling between cells is associated with specific characteristics of the presented targets. Thus, the constitution of the connectome (that is, the number of cells, their placement in the brain, their sensory selectivity) is determined by the nature of a particular stimulus.
To respond to rapidly changing stimuli, the connectome may change on the same time scale (within milliseconds). Some cells may join the connectome by strengthening their coupling, while other units may leave the group by weakening their links. Thus, the connectome is a functional unit of sorts, reflecting the characteristics of the applied stimulus.
The aim of this Research Topic is to explore the brain’s strategy to encode the immense variety of sensory inputs, often presented simultaneously. This encoding process must be accomplished with high precision in space and time domains.
We welcome all original research, review articles, methods, and data reports, on topics that include, but are not limited to:
1. Cellular responses, including neurochemical and electrophysiological
2. Synaptic transmission and circuits functions
3. Perception reactions
Keywords: visual encoding, brain oscillations, connectomes, sensory cortices, sensory stimuli
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