A measure of how rapidly cortical features change at areal boundaries also showed that the rate of change in the granule and pyramidal cell densities of layers IV and V, respectively, was greater at the borders between posterior areas than between anterior areas. This article will facilitate the anatomical identification and comparison of experimental data involving the human vmPFC. ”
“The neural processing of auditory motion information shows a pronounced interhemispheric check details asymmetry. In previous electrophysiological studies, the so-called motion-onset response (MOR), a prominent auditory-evoked potential to the onset of sound motion, was stronger over the hemisphere
contralateral to the side of motion. Here, effects of lateral-onset position and direction of motion on MOR contralaterality were investigated. Eighteen listeners were presented with free-field sound stimuli that, after an initial stationary phase at a lateral spatial position within the left or right hemifield, started to move either left- or rightward. The early part of the MOR, the so-called change-N1, exhibited contralaterality that depended on the lateral motion-onset
position with stronger activations over the hemisphere contralateral to the side of motion onset, whereas the contralaterality of the later part of the MOR, the so-called change-P2, merely depended on the direction of motion. Cortical source localization indicated that this pattern of contralaterality LGK-974 datasheet primarily resulted from asymmetric activation in primary auditory cortex and insula. These findings suggest that the early and late parts of the MOR reflect different phases in auditory motion perception, supporting the notion of a modular organization of discrete processing stages. ”
“Department of Cognitive Sciences, École Normale Supérieure, Paris, PtdIns(3,4)P2 France The
brain builds dynamic models of the body and the outside world to predict the consequences of actions and stimuli. A well-known example is the oculomotor integrator, which anticipates the position-dependent elasticity forces acting on the eye ball by mathematically integrating over time oculomotor velocity commands. Many models of neural integration have been proposed, based on feedback excitation, lateral inhibition or intrinsic neuronal nonlinearities. We report here that a computational model of the cerebellar cortex, a structure thought to implement dynamic models, reveals a hitherto unrecognized integrator circuit. In this model, comprising Purkinje cells, molecular layer interneurons and parallel fibres, Purkinje cells were able to generate responses lasting more than 10 s, to which both neuronal and network mechanisms contributed. Activation of the somatic fast sodium current by subthreshold voltage fluctuations was able to maintain pulse-evoked graded persistent activity, whereas lateral inhibition among Purkinje cells via recurrent axon collaterals further prolonged the responses to step and sine wave stimulation.