. In a number of systems including wind detection in the cricket, visual motion perception and coding of arm movement direction in the monkey and place cell response to position in the rat hippocampus, firing rates in a population of tuned neurons are correlated with a vector quantity. We examine and compare several methods that allow the coded vector to be reconstructed from measured firing rates. In cases where the neuronal tuning curves resemble cosines, linear reconstruction methods work as well as more complex statistical methods requiring more detailed information about the responses of the coding neurons. We present a new linear method, the optimal linear estimator (OLE), that on average provides the best possible linear reconstruction. This method is compared with the more familiar vector method and shown to produce more accurate reconstructions using far fewer recorded neurons. Introduction To determine how information is represented by nervous systems, we need to understand ...

. In a number of systems including wind detection in the cricket, visual motion perception and coding of arm movement direction in the monkey and place cell response to position in the rat hippocampus, firing rates in a population of tuned neurons are correlated with a vector quantity. We examine and compare several methods that allow the coded vector to be reconstructed from measured firing rates. In cases where the neuronal tuning curves resemble cosines, linear reconstruction methods work as well as more complex statistical methods requiring more detailed information about the responses of the coding neurons. We present a new linear method, the optimal linear estimator (OLE), that on average provides the best possible linear reconstruction. This method is compared with the more familiar vector method and shown to produce more accurate reconstructions using far fewer recorded neurons. Introduction To determine how information is represented by nervous systems, we need to understand...

ABSTRACT Terrestrial arthropods are challenged with locating food in a heterogeneous environment, and this activity may be mediated by the hunger level the animal is experiencing. We performed wind tunnel experiments to determine whether food deprivation in the terrestrial darkling beetles Eleodes extricata Say and Eleodes hispilabris Say affects their movement patterns and whether they orient to food by means of vision, olfaction, or both. Hunger affected foraging behavior with respect to whether beetles actually contacted food. However, the velocity and number of turns of both food-deprived and fed individuals did not significantly differ, indicating that food deprivation affects the ethological consequences but not the velocity and turning mechanics of foraging in these species. Both olfaction and vision were used to find food over short distances (<80 cm). Olfaction elicited a stronger navigational response than did vision, particularly within 25 cm of food.