Hovda D A, Villablanca J R
Department of Psychiatry, UCLA School of Medicine 90024-1759.
Behav Brain Res. 1990 Mar 5;37(2):119-32. doi: 10.1016/0166-4328(90)90087-u.
Following cerebral hemispherectomy and using a lick-suppression test, adult-lesioned cats showed a complete contralateral hemianopsia, while neonatal-lesioned animals reliably responded to stimuli presented out to 45 degrees in the visual field contralateral to the lesion. In adult-lesioned cats oxidative metabolism of the superior colliculus ipsilateral to the hemispherectomy was markedly depressed as compared to the contralateral colliculus. In contrast, in the neonatal-lesioned cats this metabolic imbalance was mild. We propose that this ipsilateral depression of oxidative metabolism reflects the loss of excitatory corticotectal input which has been postulated as being partly responsible for the hemianopsia following a unilateral visual cortex ablation. Here we demonstrate, in addition, that this phenomenon is affected by developmental factors and suggest that differential age-at-lesion anatomical effects may also be involved.
在进行大脑半球切除术后并采用舔舐抑制试验，成年期受损的猫表现出完全的对侧偏盲，而新生期受损的动物能够可靠地对在损伤对侧视野中45度范围内呈现的刺激做出反应。与对侧上丘相比，成年期受损猫的大脑半球切除同侧上丘的氧化代谢明显降低。相比之下，新生期受损的猫这种代谢失衡较为轻微。我们认为这种氧化代谢的同侧降低反映了兴奋性皮质顶盖输入的丧失，这被认为是单侧视觉皮层切除术后偏盲的部分原因。此外，我们在此证明这种现象受发育因素影响，并表明损伤时年龄的差异对解剖结构的影响可能也有作用。
