Search results for "Categorical perception"
showing 3 items of 3 documents
The Sensory Neocortex and Associative Memory
2016
Most behaviors in mammals are directly or indirectly guided by prior experience and therefore depend on the ability of our brains to form memories. The ability to form an association between an initially possibly neutral sensory stimulus and its behavioral relevance is essential for our ability to navigate in a changing environment. The formation of a memory is a complex process involving many areas of the brain. In this chapter we review classic and recent work that has shed light on the specific contribution of sensory cortical areas to the formation of associative memories. We discuss synaptic and circuit mechanisms that mediate plastic adaptations of functional properties in individual …
A Basis Set of Elementary Operations Captures Recombination of Neocortical Cell Assemblies During Basal Conditions and Learning
2019
Cell assemblies — subgroups within neuronal networks — are believed to serve as functional entities underlying cognitive capabilities such as categorical perception or memory formation and storage. However, little is known about their long-term dynamics. Using chronic in vivo calcium imaging in the mouse auditory cortex, we find that cell assemblies undergo continuous recombination, even under behaviorally stable conditions. We identify a basis set of elementary operations capturing the dynamics of cell assemblies, which involve plasticity of both the stimulus tuning of particular assemblies as well as the cellular composition of an assembly. Auditory fear conditioning introduces biases in …
Rapid categorization of sound objects in anesthetized rats as indexed by the electrophysiological mismatch response
2014
It is not known whether animals can, similarly to humans, categorize auditory objects based on an abstract rule in combining their physical features. We recorded local-field potentials from the dura above the primary auditory cortex in urethane-anesthetized rats presented with sound series occasionally violating a rule (e.g., "the higher the frequency, the weaker the intensity"). In a separate control condition, the same frequency and intensity levels were applied in the sound objects, but they obeyed no rule. Responses found selectively to the violations of the rule suggest that an abstract rule was represented in the rat brain, enabling auditory categorization.