Data from Churan et al. Action-dependent processing of self-motion in parietal cortex of macaque monkeys

Animals Two adult male monkeys (macaca mulatta) participated in the study. Single-unit recordings were done using standard tungsten microelectrodes (FHC, Bowdoin, USA) with an impedance of ~2 MΩ at 1 kHz that were positioned by an hydraulic micromanipulator (MO-95, Narishige, Tokyo, Japan). A stainless-steel guiding tube was used for transdural penetration and support of the electrode. The neuronal signal was processed using a commercial system (Alpha Omega, Nof HaGalil, Israel). It was band-pass filtered (cut-off frequencies at 500 Hz and 8000 Hz) and sampled at 44 kHz. Apparatus During recordings, the monkeys were sitting head-fixed in a primate chair in a dark room, and their eye-position was monitored at 1000 Hz using a video-based eye tracker (EyeLink 1000, SR Research, Ottawa, Canada). The chair was positioned at a distance of 97 cm from a semi-transparent screen (size 160 cm x 90 cm, subtending the central 79 deg x 50 deg of the visual field) on which the visual stimuli were back-projected using a PROPixx-projector (VPixx Technologies, St-Bruno de Montarville, Canada) running at a resolution of 1920 x 1080 pixels and at a frame rate of 100 Hz. A custom-made touch sensor (length 10 cm, diameter 1 cm) was integrated into the monkey chair in front of the monkey and its status was monitored online at a sampling rate of 1 kHz. Data processing Single units were isolated using a semi-manual spike sorter (Plexon Inc, Dallas, Texas). To this end we used a threshold on the electrode signal that was set manually to separate the action potentials from noise. The samples that exceeded the threshold were further analyzed using principal components as well as other features that were derived from the signal (like local maxima and minima). Then clusters of samples with similar properties were identified visually and each defined as representing a single unit. For a detailed description of the sorting process see the offline User Guide (Plexon, 2020). Further description of the Methods, see: Churan et al. 2021, doi: 10.1152/jn.00049.2021 Data: The file 'data_active_passive.mat' contains following variables: monkey: code for the tested monkey (1=monkey S, 2=monkey O) baseline: Mean and standard deviation of the activity in a time window of 150 ms to 20 ms before the press of the button. reaction: Mean time between the switch of the color of the fixation point from red to green and the time of the button press. anti_p: Significance of a one sided t-test between the baseline activity and activity 200 ms to 0 ms prior to the onset of stimulus motion. p_win (a (1-3),b (1-3),c (1-3),n(1-110)): 4D matrix containing p-values of t-tests a: 1: Was preparatory activity significantly higher in the passive relative to the active condition? 2: Was preparatory activity significantly lower in the passive relative to the active condition? 3: Was the tonic motion response (200 ms to 500 ms after motion onset) significantly different between the active and the passive conditions? b: 1: Calculation was made based on all motion directions 2: Calculation was made based on the preferred motion direction 3: Calculation was made based on the flanking motion directions c: 1: Calculation was made based on all presented delays 2: Calculation was made based on the shorter set of delays (500 ms to 700 ms) 3: Calculation was made based on the longer set of delays (701 ms to 1000 ms) n: number of the investigated neuron psth_alldir: cell array containing the PSTHs (obtained by convolving each spike with a Gaussian as described in the manuscript) in a time window between 1000 ms before and 800 ms after the onset of motion (in 1 ms steps). PSTHs were calculated based on data from all tested directions. Each cell array consists of 4 elements containing different conditions: 1: active condition 2: passive condition shorter set of delays (500 ms to 700 ms) 3: passive condition longer set of delays (701 ms to 1000 ms) 4: passive condition all delays psth_bestdir: same as above - using only the preferred direction psth_nbestdir: same as above - using only the flanking directions d_alldir: cell array containing the continuous d-prime (as described in the manuscript) in a time window between 1000 ms before and 800 ms after the onset of motion (in 1 ms steps). d' were calculated based on data from all tested directions. Each cell array consists of 4 elements containing different conditions: 1: active condition 2: passive condition shorter set of delays (500 ms to 700 ms) 3: passive condition longer set of delays (701 ms to 1000 ms) 4: passive condition all delays d_bestdir: same as above - using only the preferred direction d_nbestdir: same as above - using only the flanking directions The file 'timecourse_preparatory.mat' contains the cell array 'd_alldir_preparatory' that consists of 201 elements. Each of the elements contains PSTHs of 23 neurons that have exhibited significant preparatory activity in the passive condition in a time window 1000 ms to 0 ms before the motion onset. Each of the 201 elements describes a specific range of delays between button press and motion onset. This delay range is always a 100 ms wide sliding window, e.g. the element 1 represents delays between 500 and 600 ms, in element 2, the delays are between 501 and 601 ms and so on with the last element (201) representing delays between 700 and 800 ms. Some example code that re-creates most of the figures from the manuscript and that may serve as a starting point for further exploration of the data is available on request from the corresponding author.

实验动物 本研究使用2只成年雄性恒河猴（Macaca mulatta）。采用标准钨微电极（tungsten microelectrode，FHC，美国鲍登）进行单单位记录（single-unit recording），该电极在1 kHz下阻抗约为2 MΩ，通过液压微操纵器（hydraulic micromanipulator，MO-95，日本成濑（Narishige），东京）定位。使用不锈钢引导管进行硬膜外穿刺并固定电极。神经元信号通过商用系统（Alpha Omega，以色列哈加利尔诺夫（Nof HaGalil））处理，经带通滤波（截止频率为500 Hz与8000 Hz）后，以44 kHz采样率进行数字化采样。

实验装置 记录过程中，猴子头部固定于灵长类动物椅中，置于暗室内；通过基于视频的眼动追踪系统（video-based eye tracker，EyeLink 1000，加拿大SR Research，渥太华）以1000 Hz采样率实时监测眼位。动物椅与半透明屏幕（尺寸160 cm × 90 cm，覆盖视野中心79 deg × 50 deg）间距为97 cm，视觉刺激由PROPixx投影仪（VPixx Technologies，加拿大圣布鲁诺德蒙塔维尔（St-Bruno de Montarville））背投产生，该投影仪分辨率为1920 × 1080像素，帧率为100 Hz。定制触摸传感器（长度10 cm，直径1 cm）集成于猴子前方的椅面，以1 kHz采样率在线监测其触发状态。

数据处理 单单位信号通过半人工锋电位分拣器（semi-manual spike sorter，Plexon Inc，美国德克萨斯州达拉斯）分离。具体流程为：手动设置电极信号阈值，以区分动作电位（action potential）与噪声；超过阈值的样本进一步通过主成分分析（principal component analysis）及其他信号衍生特征（如局部极大值、极小值）进行分析。随后视觉识别具有相似属性的样本簇，每个簇定义为一个单单位。关于分拣流程的详细说明，请参见离线用户指南（Plexon，2020）。更多方法学细节参见：Churan等，2021，doi: 10.1152/jn.00049.2021。

数据文件说明
文件`data_active_passive.mat`包含以下变量：
1. `monkey`：受试猴子编码（1=猴子S，2=猴子O）
2. `baseline`：按钮按下前150 ms至20 ms时间窗口内神经元活动的均值与标准差
3. `reaction`：固定点颜色从红色切换为绿色至按钮按下的平均时间间隔
4. `anti_p`：基线活动与刺激运动 onset（motion onset）前200 ms至0 ms时段内活动之间的单侧t检验显著性结果
5. `p_win (a(1-3), b(1-3), c(1-3), n(1-110))`：包含t检验p值的4维矩阵，各维度含义如下：
- `a`：1=被动条件下的准备活动是否显著高于主动条件？2=被动条件下的准备活动是否显著低于主动条件？3=主动与被动条件下的紧张性运动响应（运动 onset 后200 ms至500 ms）是否存在显著差异？
- `b`：1=基于所有运动方向计算；2=基于偏好运动方向计算；3=基于侧翼运动方向计算
- `c`：1=基于所有呈现的延迟时长计算；2=基于较短延迟组（500 ms至700 ms）计算；3=基于较长延迟组（701 ms至1000 ms）计算
- `n`：受试神经元编号
6. `psth_alldir`：细胞数组（cell array），包含运动 onset 前1000 ms至运动 onset 后800 ms时间窗口内的刺激同步发放直方图（peri-stimulus time histogram, PSTH，以1 ms为步长），该PSTH通过将每个锋电位（spike）与高斯核卷积得到（详见论文），计算基于所有受试运动方向的数据。每个细胞数组包含4个对应不同实验条件的元素：1=主动条件；2=被动条件（较短延迟组：500 ms至700 ms）；3=被动条件（较长延迟组：701 ms至1000 ms）；4=被动条件（所有延迟组）
7. `psth_bestdir`：与`psth_alldir`含义一致，仅基于偏好运动方向的数据计算
8. `psth_nbestdir`：与`psth_alldir`含义一致，仅基于侧翼运动方向的数据计算
9. `d_alldir`：细胞数组，包含运动 onset 前1000 ms至运动 onset 后800 ms时间窗口内的连续d'值（d-prime，详见论文），该d'值基于所有受试运动方向的数据计算。每个细胞数组包含4个对应不同实验条件的元素：1=主动条件；2=被动条件（较短延迟组：500 ms至700 ms）；3=被动条件（较长延迟组：701 ms至1000 ms）；4=被动条件（所有延迟组）
10. `d_bestdir`：与`d_alldir`含义一致，仅基于偏好运动方向的数据计算
11. `d_nbestdir`：与`d_alldir`含义一致，仅基于侧翼运动方向的数据计算

文件`timecourse_preparatory.mat`包含细胞数组`d_alldir_preparatory`，共包含201个元素。每个元素对应23个神经元的PSTH，这些神经元在运动 onset 前1000 ms至0 ms时段的被动条件下表现出显著的准备活动。201个元素各自对应按钮按下至运动 onset 之间的一个特定延迟范围，每个延迟范围均为宽度100 ms的滑动窗口：例如第1个元素对应500 ms至600 ms的延迟，第2个元素对应501 ms至601 ms的延迟，以此类推，最后1个元素（第201个）对应700 ms至800 ms的延迟。

可向通讯作者索取示例代码，该代码可复现论文中大部分图表，亦可作为进一步探索数据的起点。