当前位置: X-MOL 学术J. Neurosci. › 论文详情
Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)
Double Dissociation of Spontaneous Alpha-Band Activity and Pupil-Linked Arousal on Additive and Multiplicative Perceptual Gain
Journal of Neuroscience ( IF 5.3 ) Pub Date : 2024-05-08 , DOI: 10.1523/jneurosci.1944-23.2024
April Pilipenko , Jason Samaha

Perception is a probabilistic process dependent on external stimulus properties and one's internal state. However, which internal states influence perception and via what mechanisms remain debated. We studied how spontaneous alpha-band activity (8–13 Hz) and pupil fluctuations impact visual detection and confidence across stimulus contrast levels (i.e., the contrast response function, CRF). In human subjects of both sexes, we found that low prestimulus alpha power induced an "additive" shift in the CRF, whereby stimuli were reported present more frequently at all contrast levels, including contrast of zero (i.e., false alarms). Conversely, prestimulus pupil size had a "multiplicative" effect on detection such that stimuli occurring during large pupil states (putatively corresponding to higher arousal) were perceived more frequently as contrast increased. Signal detection modeling reveals that alpha power changes detection criteria equally across the CRF but not detection sensitivity (d'), whereas pupil-linked arousal modulated sensitivity, particularly for higher contrasts. Interestingly, pupil size and alpha power were positively correlated, meaning that some of the effect of alpha on detection may be mediated by pupil fluctuations. However, pupil-independent alpha still induced an additive shift in the CRF corresponding to a criterion effect. Our data imply that low alpha boosts detection and confidence by an additive factor, rather than by a multiplicative scaling of contrast responses, a profile which captures the effect of pupil-linked arousal. We suggest that alpha power and arousal fluctuations have dissociable effects on behavior. Alpha reflects the baseline level of visual excitability, which can vary independent of arousal.



中文翻译:

自发阿尔法带活动和瞳孔相关唤醒对加法和乘法知觉增益的双重解离

感知是一个依赖于外部刺激特性和内部状态的概率过程。然而,哪些内部状态影响感知以及通过哪些机制仍然存在争议。我们研究了自发 α 波段活动(8-13 Hz)和瞳孔波动如何影响刺激对比度水平(即对比度响应函数,CRF)的视觉检测和置信度。在男女受试者中,我们发现低刺激前 α 功率会引起 CRF 的“加性”变化,据报道,刺激在所有对比度水平下更频繁地出现,包括零对比度(即误报)。相反,刺激前瞳孔大小对检测具有“倍增”效应,使得随着对比度的增加,在大瞳孔状态(假定对应于更高的唤醒)期间发生的刺激被更频繁地感知。信号检测模型表明,α 功率会均匀地改变整个 CRF 的检测标准,但不会改变检测灵敏度 ( d '),而瞳孔相关的唤醒调制灵敏度,特别是对于更高的对比度。有趣的是,瞳孔大小和阿尔法强度呈正相关,这意味着阿尔法对检测的一些影响可能是由瞳孔波动介导的。然而,与瞳孔无关的 α 仍然会引起 CRF 中与标准效应相对应的加性偏移。我们的数据表明,低阿尔法通过加法因子提高检测和置信度,而不是通过对比反应的乘法缩放,该曲线捕获了瞳孔相关唤醒的效果。我们认为阿尔法功率和唤醒波动对行为具有分离的影响。 Alpha 反映了视觉兴奋性的基线水平,其变化与唤醒无关。

更新日期:2024-05-09
down
wechat
bug