Use of Amantadine in Parkinson's Disease. Results of a Double-blind Trial

Abstract

<h3>Abstract</h3> Movement-related neuronal discharge in ventral tegmental area (VTA) and ventral pallidum (VP) is inconsistently observed across studies. One possibility is that some neurons are movement-related and others are not. Another possibility is that the precise behavioral conditions matter - that a single neuron can be movement related under certain behavioral states but not others. We recorded single VTA and VP neurons in birds transitioning between singing and non-singing states, while monitoring body movement with microdrive-mounted accelerometers. Many VP and VTA neurons exhibited body movement-locked activity exclusively when the bird was not singing. During singing, VP and VTA neurons could switch off their tuning to body movement and become instead precisely time-locked to specific song syllables. These changes in neuronal tuning occurred rapidly at state boundaries. Our findings show that movement-related activity in limbic circuits can be gated by behavioral context. <h3>Significance statement</h3> Neural signals in the limbic system have long been known to represent body movements as well as reward. Here we show that single neurons dramatically change their tuning to movements when a bird starts to sing.