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‘Unting is all that's worth living for – all time is lost wot is not spent in ‘unting – it is like the hair we breathe – if we have it not we die – it's the sport of kings. The most vital possessions of the plant are the chloroplasts in the cells of its leaves. Through these, the organism can convert, for its own purposes, a fraction of the solar energy that falls upon it. Sunlight is remarkably uniform in its intensity, and a plant has little to gain by moving about. It can thus afford a relatively stationary existence, the only motion being that required to reach regions beyond the shade of its immediate environment and its competitors. Because they have no chloroplast-bearing cells, animals have paid the penalty of having to develop several specialized functions in order to satisfy their energy requirements. They must have a means of locomotion and feeding, and some form of coordination of these faculties, however primitive, is needed. And as insurance against the unsuccessful forage, they should be able to store digested energy. Moreover, unless an animal is so small that the normal process of diffusion is adequate, it must have a circulatory system to distribute dissolved gases and chemical compounds to its various parts. [ABSTRACT FROM AUTHOR]

In the antisaccade task, subjects are instructed to look in the opposite direction of a visually presented stimulus. Controls can perform this task successfully with very few errors, whereas schizophrenia patients make more errors and their responses are slower and more variable. It has been proposed the fundamental cognitive dysfunction in schizophrenia involves prefrontal dopaminergic hypoactivity. We examine via computer simulations the effects of dopamine on the variability of aSRTs in a neural cortico-collicular accumulator model with stochastic climbing activity. We report the simulated aSRTs for the hypo-DA level have higher standard deviation and mean values than in the normal and hyper DA level. The simulated higher mean and standard deviation for the hypo-DA group resemble the performance differences in the antisaccade task observed in patients with schizophrenia and are in accordance with the theory of a hypo-DA state in the frontal cortical areas of patients with schizophrenia. [ABSTRACT FROM AUTHOR]

The purpose of this study was to develop an algorithm capable of transforming neural activity to correctly report behavioral outcome during a cognitive task. We recorded from small groups of 2-5 neurons in the superior colliculus (SC) while monkeys performed a go/no-go task. Depending upon the color of a peripheral stimulus, the monkey was required to either make a saccade to the stimulus (go) or maintain fixation (no-go). In order to replicate the progress of the decision-making process and generate a virtual decision function (VDF), we performed a multiple regression analysis, with 1 msec resolution, on neuron activity during individual trials. Post hoc analyses by VDF predicted the monkey΄s choice with nearly 90% accuracy. These results suggest that monitoring of a limited number of SC neurons has sufficient capacity to predict go/no-go decisions on a trial-by-trial basis, and serves as an ideal candidate for a cognitive brain-machine interface (BMI). [ABSTRACT FROM AUTHOR]