Spatial effects of shifting prisms on properties of posterior parietal cortex neurons.
Spatial effects of shifting prisms on properties of posterior parietal cortex neurons.
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移动棱镜对后顶叶皮层神经元特性的空间影响。
DOI：
10.1113/jphysiol.2014.270942
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发表时间：
2014
期刊：
影响因子：
--
通讯作者：
Siegel,RalphM
中科院分区：
文献类型：
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作者：
Karkhanis,AnushreeN;Heider,Barbara;Silva,FabianMuñoz;Siegel,RalphM
关键点后顶叶皮层包含多种空间表征，参与视觉引导手部运动的在线监测。在视觉引导到达任务中，对猕猴后顶叶皮层的两个区域进行了单单位记录。为了测试神经反应的适应性，移动棱镜被引入，以产生感知和实际到达位置之间的差异。大多数神经元改变了平均放电率和/或在棱镜曝光期间的眼睛位置调谐。调谐变化的方向与棱镜移位的方向无关，使用欧拉角和平移的人口分析表明，支持这一概念的条件之间的系统转换，后顶叶皮层包含对视觉刺激和运动行为做出反应的神经元。本研究的目的是测试猕猴7a区和背月前肌神经元在视觉引导下使用菲涅耳棱镜移位视野时的短期适应。视觉扰动改变了眼睛的位置，并在感知和实际到达位置之间产生了不匹配。在棱镜暴露之前、期间和之后，训练两只非人灵长类动物到达视觉目标，同时将到达目标固定在不同位置。他们被要求到达到达目标的物理位置，而不是感知到的位移位置。虽然在几次试验中发生了对棱镜的行为适应，但大多数神经元对空间眼位置调谐的实质性变化或整体放电率的变化做出了反应。这些变化甚至在移除棱镜后仍然存在。空间变化与诱导棱镜移位的方向无关。通过计算欧拉角中的平移和旋转，估计了增益场在条件之间的变换。旋转和平移的水平和垂直的空间分量发生在一个系统的方式为人口的神经元，这表明后顶叶皮层保留了恒定的代表性的实验条件之间的视野重新映射。
Key pointsThe posterior parietal cortex contains multiple spatial representations and is involved in online monitoring of visually guided hand movements.Single unit recordings were performed in two areas of macaque monkey posterior parietal cortex during a visually guided reaching task with variable eye position.To test the adaptability of neural responses, shifting prisms were introduced to create a discrepancy between perceived and actual reach location.The majority of neurons changed average firing rate and/or eye position tuning during the prism exposure.The direction of tuning change did not correlate with the direction of prism shift, suggesting more generalized network effects due to the perturbation.Population analysis using Euler angles and translations demonstrated systematic transformations between conditions supporting the notion of network behaviour.AbstractThe posterior parietal cortex contains neurons that respond to visual stimulation and motor behaviour. The objective of the current study was to test short‐term adaptation in neurons in macaque area 7a and the dorsal prelunate during visually guided reaching using Fresnel prisms that displaced the visual field. The visual perturbation shifted the eye position and created a mismatch between perceived and actual reach location. Two non‐human primates were trained to reach to visual targets before, during and after prism exposure while fixating the reach target in different locations. They were required to reach to the physical location of the reach target and not the perceived, displaced location. While behavioural adaptation to the prisms occurred within a few trials, the majority of neurons responded to the distortion either with substantial changes in spatial eye position tuning or changes in overall firing rate. These changes persisted even after prism removal. The spatial changes were not correlated with the direction of induced prism shift. The transformation of gain fields between conditions was estimated by calculating the translation and rotation in Euler angles. Rotations and translations of the horizontal and vertical spatial components occurred in a systematic manner for the population of neurons suggesting that the posterior parietal cortex retains a constant representation of the visual field remapping between experimental conditions.