Diogo Antonia Cinira M, Lima Bruss, Soares Juliana G M, Gattass Ricardo
Universidade Federal do Rio de Janeiro, Instituto de Biofísica Carlos Chagas Filho, Av. Carlos Chagas Filho 373, Bloco G, Cidade Universitária, 21941-900 Rio de Janeiro, RJ, Brazil.
An Acad Bras Cienc. 2020 Jun 12;92(2):e20190564. doi: 10.1590/0001-3765202020190564. eCollection 2020.
We studied the multiunit responses to moving and static stimuli from 585 cell clusters in area MT using multi-electrode arrays. Our aim was to explore if MT columns exhibit any larger-scale tangential organization or clustering based on their response properties. Neurons showing both motion and orientation selectivity were classified into four categories: 1- Type I (orientation selectivity orthogonal to the axis of motion); 2- Type II (orientation selectivity coaxial to the axis of motion); 3- Type DS (significant response to moving stimuli, but non-significant response to static stimuli); and 4- Type OS (significant orientation selectivity, but non-significant direction selectivity). Type I (34%), Type II (24%) and Type DS (32%) clusters were the most predominant and may be associated with different stages of motion processing in MT. On the other hand, the rarer Type OS (9%) may be integrating motion and form processing. Type I and unidirectional sites were the only classes to exhibit significant clustering. Type OS sites showed a trend for clustering, which did not reach statistical significance. We also found a trend for unidirectional sites to have bidirectional sites as neighbors. In conclusion, neuronal clustering associated with these four categories may be related to distinct MT functional circuits.
我们使用多电极阵列研究了MT区585个细胞簇对移动和静态刺激的多单元反应。我们的目的是探究MT柱是否基于其反应特性呈现出任何更大尺度的切向组织或聚类。显示运动和方向选择性的神经元被分为四类：1-I型（方向选择性与运动轴正交）；2-II型（方向选择性与运动轴同轴）；3-DS型（对移动刺激有显著反应，但对静态刺激无显著反应）；4-OS型（有显著的方向选择性，但无显著的方向选择性）。I型（34%）、II型（24%）和DS型（32%）簇最为常见，可能与MT区运动处理的不同阶段相关。另一方面，较罕见的OS型（9%）可能在整合运动和形状处理。I型和单向位点是仅有的呈现显著聚类的类别。OS型位点显示出聚类趋势，但未达到统计学显著性。我们还发现单向位点有双向位点作为邻居的趋势。总之，与这四类相关的神经元聚类可能与不同的MT功能回路有关。
