Encoding of Dynamic Visual Stimuli by Primate Area MT Neurons

Neural stimulus selectivity is thought to be optimized for the representation of real-world stimuli. Neural coding properties, therefore, may adapt to different environments. Here, we address the question if tuning curves depend on the statistics of visual stimuli. This is done by studying the directional tuning of macaque area MT neurons exposed to dynamic motion stimuli of two different direction progression statistics. Despite an apparent difference of tuning curves across stimulus conditions, our results support the view that the underlying encoding system is robust and subject to only restricted malleability by stimulus statistics. Key words: directional tuning, stimulus statistics, area MT, reverse correlation

Stimulus Representation in Rat Primary Visual Cortex: Multi-Electrode Recordings With Micromachined Silicon Probes and Estimation Theory

The study of neural population codes relies on massively parallel recordings in combination with theoretically motivated analysis tools. We applied two multi-site recording techniques to record from cells throughout cortical depth in a minimally invasive way. The feasibility of such experiments in area 17 of the anesthetized rat is demonstrated. Bayesian reconstruction and the interpretative framework of Fisher information are introduced. We demonstrate applicability and usefulness of Bayesian stimulus reconstruction and show that even small numbers of neurons can yield a high degree of representational accuracy under favorable conditions. Results are discussed and future lines of research outlined