Cluster B: Population coding in the early sensory cortex
The cortex is thought to be critical for integrating inputs from all primary sensory areas and for carrying out important computations underlying perceptual inference. Although there is extensive knowledge about how single cortical neurons operate in isolation, we do not know how to place this back into the context of an interconnected, operating system. Moreover, we do not know which algorithms are suitable to describe how the sensory input has been processed up to this stage. Here, we will work towards identifying these algorithms. To this end, we will investigate early cortical processing of perceptually relevant stimuli at the level of populations rather than single cells in awake, behaving animals making use of new technologies that allow simultaneous recordings from neuronal populations. As cortical representations are likely to share generic principles across sensory modalities, we will furthermore compare coding properties in primary visual, somatosensory, and auditory cortex. The central research questions are:
- Which interactions among cortical cells are critical for stimulus encoding and which are critical for triggering behaviour?
- To what extent can we predict the animals’ choice from the primary sensory cortex on a single trial basis?
- How stable is the neuronal representation of a stimulus from one trial to the next?
- How is prior knowledge about the natural sensory input stored and recalled in cortical representations?
B1 Transformation of input correlation to V1 spike correlations and behavioural choice in the awake monkey.
B2 Imaging neuronal population coding during perception in awake, behaving animals.
Kerr, Schwarz, Bethge
B3 The role of slow network fluctuations in robust population coding.
Kayser, Logothetis, Panzeri
B4 Changing codes by reward: from the model to the neuronal population.