Modulation of Collicular Function

上丘是包括人类在内的所有哺乳动物中脑中的一个小的视觉核，在控制视觉定向和视觉注意方面发挥着重要作用。以前的大多数研究都是关于特定的感觉输入，以了解它是如何参与这些行为的。然而，上丘也有来自其他系统的输入，这些系统不被认为是传递特定的感觉信息，但也可以影响丘细胞的反应。其中最突出的是去甲肾上腺素的输入，它似乎对注意力有很大的影响。这项研究将研究去甲肾上腺素对上丘的信息处理是如何调节的，包括：(1)许多不同类型的细胞中的哪些细胞受到这种神经递质的影响，(2)与细胞反应性变化相关的膜和/或离子事件，以及(3)这种神经递质影响的回路。为了分析去甲肾上腺素对神经元的影响，使用了非常精细的电极来记录神经元的活动。其他正在使用的技术结合了免疫细胞化学和电子显微镜，以了解上丘输入的突触组织。

The superior colliculus is a small, visual nucleus in the midbrain of all mammals including humans and plays a major role in the control of visual orientation and visual attention. Most of the previous research to understand how it participates in these behaviors has been concerned with specific sensory inputs. However, the superior colliculus also has inputs from other systems not thought to convey specific sensory information, but which can also influence the responses of collicular cells. The most prominent of these is the noradrenergic input which appears to have strong influences upon attention. This research will examine how the noradrenergic input to the superior colliculus modulates information-processing in this nucleus, including: (1) which of the many different types of cells are affected by this neurotransmitter, (2) the membrane and/or ionic events associated with changes in cellular responsiveness, and (3) the circuitry underlying the effects of this neurotransmitter. Very fine electrodes are used to record the activity of neurons in order to assay the effects of norepinephrine on neurons. Other techniques being used combine immunocytochemistry and electron microscopy in order to understand the synaptic organization of inputs to the superior colliculus.