Pan Jasmine, Vinke Louis N, McGuire Joseph T, Ling Sam
Psychological & Brain Sciences, Boston University, Boston, Massachusetts 02215
Center for Systems Neuroscience, Boston University, Boston, Massachusetts 02215.
J Neurosci. 2025 Jun 18;45(25):e0798242025. doi: 10.1523/JNEUROSCI.0798-24.2025.
While animal studies have found that arousal states modulate visual responses, direct evidence for effects of arousal on human vision remains limited. Here, we used fMRI to examine effects of cognitive arousal on the gain of contrast response functions (CRFs) in human visual cortex. To measure CRFs, we measured BOLD responses in early visual cortex (V1-V3) while participants ( = 20, 14 females and 6 males) viewed stimuli that parametrically varied in contrast. To induce different cognitive arousal states, participants solved auditory arithmetic problems categorized as either Easy (low arousal) or Hard (high arousal). We found diversity in the modulatory effects across individuals: some individuals exhibited enhanced neural response with increased arousal, whereas others exhibited the opposite effect-a decrease in response with increased arousal. The pattern of overall BOLD modulation showed within-individual stability and was correlated with the degree of arousal-driven change in pupil size. Individuals who exhibited larger increases in pupil size with the arousal manipulation tended to show greater arousal-related decreases in visuocortical responses. We speculate that the polarity of the modulatory effect by cognitive arousal may relate to individual differences in cognitive effort expended in the high-difficulty condition, with individuals reaching different points on an underlying non-monotonic function.
虽然动物研究发现觉醒状态会调节视觉反应，但关于觉醒对人类视觉影响的直接证据仍然有限。在这里，我们使用功能磁共振成像（fMRI）来研究认知觉醒对人类视觉皮层中对比度反应函数（CRF）增益的影响。为了测量CRF，我们在参与者（n = 20，14名女性和6名男性）观看对比度参数变化的刺激时，测量早期视觉皮层（V1-V3）中的血氧水平依赖（BOLD）反应。为了诱导不同的认知觉醒状态，参与者解决分为简单（低觉醒）或困难（高觉醒）的听觉算术问题。我们发现个体间的调节作用存在差异：一些个体随着觉醒增加表现出增强的神经反应，而另一些个体则表现出相反的效果——随着觉醒增加反应减少。总体BOLD调节模式显示个体内部具有稳定性，并且与觉醒驱动的瞳孔大小变化程度相关。在觉醒操作中瞳孔大小增加幅度较大的个体，其视觉皮层反应往往表现出更大的与觉醒相关的减少。我们推测，认知觉醒调节作用的极性可能与在高难度条件下所付出的认知努力的个体差异有关，个体在一个潜在的非单调函数上达到不同的点。
