Ehmer Birgit, Gronenberg Wulfila
Arizona Research Laboratories Division of Neurobiology, University of Arizona, Tucson, Arizona 85721, USA.
J Comp Neurol. 2004 Feb 2;469(2):198-213. doi: 10.1002/cne.11014.
The mushroom bodies are brain centers involved in complex behaviors such as learning and orientation. Here we examine the organization of mushroom bodies in ants, focusing on visual input. We describe the structure of visual neurons and compare the volume of brain structures involved in visual processing, especially the optic lobes and parts of the mushroom bodies receiving visual input in males, winged females, and workers of carpenter ants (Camponotus). A relatively small number of neurons connect the medulla with the mushroom bodies, and these neurons have relatively large dendritic fields in the medulla, suggesting low spatial resolution in ants. These neurons terminate in different yet overlapping strata in the mushroom bodies' collar region. While males have larger optic lobes than workers, their collar region is smaller than in females. Male ants have an additional type of medulla-mushroom body neuron with dendrites probing the distal medulla. These neurons are absent in female and worker ants. Most mushroom body Kenyon cells that are postsynaptic to visual input neurons appear to integrate visual as well as antennal input. This is in contrast to honey bees, where visual input to the mushroom bodies is more prominent and where Kenyon cells are not known to combine visual and antennal input.
蘑菇体是参与学习和定向等复杂行为的脑中心。在此，我们研究蚂蚁蘑菇体的组织结构，重点关注视觉输入。我们描述了视觉神经元的结构，并比较了参与视觉处理的脑结构的体积，特别是在雄性、有翅雌性和木匠蚁（弓背蚁属）工蚁中参与视觉处理的视叶和接收视觉输入的蘑菇体部分。相对较少数量的神经元将髓质与蘑菇体相连，并且这些神经元在髓质中具有相对较大的树突场，这表明蚂蚁的空间分辨率较低。这些神经元在蘑菇体的颈环区域终止于不同但重叠的层。虽然雄性的视叶比工蚁大，但它们的颈环区域比雌性小。雄性蚂蚁有一种额外类型的髓质 - 蘑菇体神经元，其树突探测远端髓质。这些神经元在雌性和工蚁中不存在。大多数作为视觉输入神经元突触后神经元的蘑菇体肯扬细胞似乎整合了视觉和触角输入。这与蜜蜂形成对比，在蜜蜂中，蘑菇体的视觉输入更为突出，并且肯扬细胞不被认为会结合视觉和触角输入。
