University of Pisa, Pisa, Italy.
IRCCS Stella Maris, Pisa, Italy.
Elife. 2022 Apr 6;11:e74565. doi: 10.7554/eLife.74565.
While there is evidence that the visual cortex retains a potential for plasticity in adulthood, less is known about the subcortical stages of visual processing. Here, we asked whether short-term ocular dominance plasticity affects the human visual thalamus. We addressed this question in normally sighted adult humans, using ultra-high field (7T) magnetic resonance imaging combined with the paradigm of short-term monocular deprivation. With this approach, we previously demonstrated transient shifts of perceptual eye dominance and ocular dominance in visual cortex (Binda et al., 2018). Here, we report evidence for short-term plasticity in the ventral division of the pulvinar (vPulv), where the deprived eye representation was enhanced over the nondeprived eye. This vPulv plasticity was similar as previously seen in visual cortex and it was correlated with the ocular dominance shift measured behaviorally. In contrast, there was no effect of monocular deprivation in two adjacent thalamic regions: dorsal pulvinar and Lateral Geniculate Nucleus. We conclude that the visual thalamus retains potential for short-term plasticity in adulthood; the plasticity effect differs across thalamic subregions, possibly reflecting differences in their corticofugal connectivity.
虽然有证据表明,视觉皮层在成年后仍具有可塑性的潜力,但对于视觉处理的皮质下阶段知之甚少。在这里,我们想知道短期的眼优势可塑性是否会影响人类的视觉丘脑。我们在正常视力的成年人类中通过使用超高场(7T)磁共振成像结合短期单眼剥夺范式来解决这个问题。通过这种方法,我们之前证明了在视觉皮层中存在短暂的感知眼优势和眼优势的转变(Binda 等人,2018 年)。在这里,我们报告了在丘脑枕腹侧部(vPulv)存在短期可塑性的证据,在该部位,被剥夺眼的代表被增强,而未被剥夺眼的代表则被抑制。这种 vPulv 可塑性与之前在视觉皮层中观察到的相似,并且与行为上测量的眼优势转变相关。相比之下,在两个相邻的丘脑区域:丘脑枕背侧部和外侧膝状体核,没有单眼剥夺的影响。我们得出结论,视觉丘脑在成年后仍具有短期可塑性的潜力;可塑性效应在不同的丘脑亚区之间存在差异,这可能反映了它们与皮质的传出连接的差异。