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The center-out task is a standard paradigm often used to study the neural control of reaching movements in human and non-human primates. However, there are several disadvantages to the use of monkeys, notably costs, infrastructural requirements, and ethical considerations. Here we describe a similar task designed to examine forelimb movements in rats. Rats were trained to grasp a joystick with their forepaw and use it to control the movements of a sipper tube in two dimensions. The rats learned to move the joystick in four directions with at least 70% accuracy after about 45 days of training. In addition, rats were able to learn a reversed mapping between joystick and sipper tube movement. This is a more complicated behavior than has been previously demonstrated for rats, and it could allow more motor behavior studies to be conducted in rodents instead of monkeys. We currently are using this behavior to decode the rats' forelimb movements from their brain signals., (Copyright © 2010 Elsevier B.V. All rights reserved.)

Using T2-weighted Magnetic Resonance Imaging (MRI) in a pyrithiamin-treated, thiamin deficient (TD) rat model of Wernicke's encephalopathy (WE), we have observed hyperintensity in the thalamus, hypothalamus, collicular bodies and hippocampus which was enhanced 40 min after a glucose load. Hyperintensity was not evident in these structures in thiamin replete rats receiving glucose nor was it enhanced in TD rats administered 2-deoxyglucose. Residual hyperintensity was still evident in the hippocampus as long as 30 days after thiamin administration and was increased by repeat glucose challenge at that time. These data indicate that the hippocampus is as vulnerable as the thalamus to some persistent pathological change when glucose is metabolised in a state of thiamin deficiency., (Copyright 1998 Elsevier Science B.V.)