Chalupa L M, Coyle R S, Lindsley D B
J Neurophysiol. 1976 Mar;39(2):354-69. doi: 10.1152/jn.1976.39.2.354.
This study compares the performance (percent correct responses and reaction times) of three unoperated control monkeys with the postoperative performance of eight monkeys with pulvinar lesions, either inferior pulvinar or medial and lateral pulvinar, on a tachistoscopically presented visual pattern-discrimination task highly demanding of attention. To further emphasize and assess the attentional factor in visual pattern discrimination, all monkeys who attained criterion performance (90% correct response on three consecutive sessions of 100 trials each) were tested for the effects of visually distracting interference stimuli added to the original discriminative stimuli. In addition, retention of postoperatively learned discriminations was tested after a 6-wk interval withou training and compared with the performance of control monkeys. Four monkeys with only inferior pulvinar lesions and one monkey with inferior pulvinar plus medial and lateral pulvinar lesions were markedly impaired in the postoperative learning of a visual pattern discrimination. Three of these monkeys failed to acquire criterion perfromance in 9,000 or more training trials, while two learned to ceiterion level only after prolonged training (7,400 and 6,900 trials). In contrast, monkeys with medial and lateral pulvinar lesions showed no deficit in learning ability compared to unoperated control monkeys. Furthermore, the performance of the two monkeys with inferior pulvinar lesions, who attained the criterion level of learning only with difficulty, was further impaired by the addition of distracting interference stimuli, where the performance of monkeys with medial and lateral pulvinar lesions as well as the control monkeys was only temporarily disrupted by this procedure. None of the monkeys with pulvinar lesions, who were tested for retention of the postoperatively learned discrimination, showed appreciable deficits in comparison to control monkeys. All monkeys, including controls and those uith pulvinar lesions who were able to learn the visual pattern discrimination, showed a common pattern of reaction time (RT) change during the course of the learning; that is, RT was low during change-level performance, increased during learning, and decreased once criterion performance was achieved. Reaction times of monkeys with inferior pulvinar lesions tended to be longer than for controls or for those with medial and lateral pulvinar lesions. These results provide the first behavior evidence that the inferior pulvinar of monkeys is involved in visual pattern discrimination and add further support to the concept of a second visual system in which the inferior pulvinar plays a role. The attentional aspects of the visual pattern-discrimination task employed in this study and the additional effects obtained with distracting stimuli suggest that the impairments arising from inferior pulvinar lesions may be dependent in part on visual attentional factors.
本研究比较了三只未手术的对照猴子与八只患有丘脑枕病变（丘脑枕下部或丘脑枕内侧和外侧）的猴子在一项对注意力要求很高的速示视觉模式辨别任务中的表现（正确反应百分比和反应时间）。为了进一步强调和评估视觉模式辨别中的注意力因素，对所有达到标准表现（在连续三个100次试验的会话中正确反应率达到90%）的猴子进行测试，以观察添加到原始辨别刺激中的视觉干扰刺激的影响。此外，在间隔6周未训练后测试术后习得辨别的保持情况，并与对照猴子的表现进行比较。四只仅患有丘脑枕下部病变的猴子和一只患有丘脑枕下部加内侧和外侧丘脑枕病变的猴子在术后视觉模式辨别的学习中明显受损。其中三只猴子在9000次或更多的训练试验中未能达到标准表现，而另外两只猴子仅在长时间训练（7400次和6900次试验）后才达到标准水平。相比之下，患有丘脑枕内侧和外侧病变的猴子与未手术的对照猴子相比，学习能力没有缺陷。此外，两只仅患有丘脑枕下部病变且仅勉强达到学习标准水平的猴子，在添加干扰刺激后表现进一步受损，而患有丘脑枕内侧和外侧病变的猴子以及对照猴子的表现仅因该程序而暂时中断。在测试术后习得辨别保持情况的丘脑枕病变猴子中，与对照猴子相比，没有一只表现出明显缺陷。所有猴子，包括对照猴子和那些能够学会视觉模式辨别的丘脑枕病变猴子，在学习过程中都表现出一种共同的反应时间（RT）变化模式；也就是说，在变化水平表现期间RT较低，在学习期间增加，一旦达到标准表现则下降。患有丘脑枕下部病变的猴子的反应时间往往比对照猴子或患有丘脑枕内侧和外侧病变的猴子更长。这些结果提供了首个行为证据，表明猴子的丘脑枕下部参与视觉模式辨别，并进一步支持了存在第二个视觉系统的概念，其中丘脑枕下部起作用。本研究中使用的视觉模式辨别任务的注意力方面以及干扰刺激产生的额外效应表明，丘脑枕下部病变引起的损伤可能部分取决于视觉注意力因素。
