Adaptation can optimize information processing by allowing the visual system to always adjust to the environment. However, only a few studies have investigated how the visual system makes adjustments to repeatedly occurring changes in the input, still less about the related neural mechanism. Our previous study found that contrast adaptation attenuated after multiple daily sessions of repeated adaptation, which was explained by the habituation of either the adapter’s effective strength or the adaptation mechanisms. To examine the former hypothesis, in the present study we used the frequency tagging technique to measure the adapter-elicited steady-state visual evoked potential (SSVEP) amplitudes. Participants repeatedly adapted to the same contrast adapter in a top-up manner for six continuous days, which was called training of adaptation. The behavioral adaptation effect and SSVEP response to the trained adapter and an untrained control adapter were measured before and after training. The psychophysical results showed that the effect of adaptation in the trained condition significantly reduced after training, replicating our previous finding. Contradicting the prediction of the hypothesis that repeated adaptation attenuated the effective strength of the adapter, the SSVEP amplitude was unchanged after training, which was further confirmed by an equivalence test. Taken together, the results challenge the account of habituation of adapter in repeated adaptation, while leaving the account of habituation of adaptation mechanism to be tested.

中文翻译：

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反复对比适应不会导致适配器习惯

适应性可以通过让视觉系统始终适应环境来优化信息处理。然而，只有少数研究调查了视觉系统如何对重复发生的输入变化进行调整，更不用说相关的神经机制。我们之前的研究发现，每天多次重复适应后，对比适应减弱，这可以通过适应器的有效强度或适应机制的习惯化来解释。为了检查前一个假设，在本研究中，我们使用频率标记技术来测量适配器引发的稳态视觉诱发电位 (SSVEP) 振幅。参与者连续六天以充值的方式反复适应相同的对比适配器，这称为适应训练。在训练前后测量了对受过训练的适配器和未经训练的控制适配器的行为适应效果和 SSVEP 响应。心理物理学结果表明，训练后适应条件的影响显着降低，重复了我们之前的发现。与重复适应减弱适配器有效强度假设的预测相反，SSVEP幅度在训练后没有变化，这通过等效性测试得到进一步证实。综上所述，结果挑战了重复适应中适配器习惯化的解释，同时对适应机制的习惯化的解释进行了测试。心理物理学结果表明，训练后适应条件的影响显着降低，重复了我们之前的发现。与重复适应减弱适配器有效强度假设的预测相反，SSVEP幅度在训练后没有变化，这通过等效性测试得到进一步证实。综上所述，这些结果挑战了重复适应中适配器的习惯化，同时对适应机制的习惯化进行了测试。心理物理学结果表明，训练后适应条件的影响显着降低，重复了我们之前的发现。与重复适应减弱适配器有效强度假设的预测相反，SSVEP幅度在训练后没有变化，这通过等效性测试得到进一步证实。综上所述，结果挑战了重复适应中适配器习惯化的解释，同时对适应机制的习惯化的解释进行了测试。训练后 SSVEP 振幅没有变化，这通过等效性测试得到进一步证实。综上所述，结果挑战了重复适应中适配器习惯化的解释，同时对适应机制的习惯化的解释进行了测试。训练后 SSVEP 振幅没有变化，这通过等效性测试得到进一步证实。综上所述，结果挑战了重复适应中适配器习惯化的解释，同时对适应机制的习惯化的解释进行了测试。