Laboratory of Sensorimotor Research, National Eye Institute, Bethesda, United States.
Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, United States.
Elife. 2022 Mar 8;11:e74168. doi: 10.7554/eLife.74168.
Recent evidence suggests that microsaccades are causally linked to the attention-related modulation of neurons-specifically, that microsaccades toward the attended location are required for the subsequent changes in firing rate. These findings have raised questions about whether attention-related modulation is due to different states of attention as traditionally assumed or might instead be a secondary effect of microsaccades. Here, in two rhesus macaques, we tested the relationship between microsaccades and attention-related modulation in the superior colliculus (SC), a brain structure crucial for allocating attention. We found that attention-related modulation emerged even in the absence of microsaccades, was already present prior to microsaccades toward the cued stimulus, and persisted through the suppression of activity that accompanied all microsaccades. Nonetheless, consistent with previous findings, we also found significant attention-related modulation when microsaccades were directed toward, rather than away from, the cued location. Thus, despite the clear links between microsaccades and attention, microsaccades are not necessary for attention-related modulation, at least not in the SC. They do, however, provide an additional marker for the state of attention, especially at times when attention is shifting from one location to another.
最近的证据表明，微扫视与与注意力相关的神经元调节有因果关系——具体来说，微扫视到注视位置是随后的发放率变化所必需的。这些发现引发了一些问题，即注意力相关的调制是由于传统上假设的不同注意力状态，还是可能是微扫视的次要影响。在这里，我们在两只恒河猴中测试了微扫视和上丘（SC）中与注意力相关的调制之间的关系，SC 是分配注意力的关键脑结构。我们发现，即使在没有微扫视的情况下，也会出现与注意力相关的调制，而且这种调制在微扫视朝向提示刺激之前就已经存在，并且在伴随着所有微扫视的活动抑制过程中仍然存在。尽管如此，与之前的发现一致，当微扫视指向提示位置而不是远离提示位置时，我们也发现了显著的与注意力相关的调制。因此，尽管微扫视与注意力之间存在明显的联系，但微扫视对于与注意力相关的调制并不是必需的，至少在上丘中不是。然而，它们为注意力状态提供了一个额外的标记，尤其是在注意力从一个位置转移到另一个位置的时候。
