Our goal was to assess the role of timing in pigeons' performance in the midsession reversal task. In discrete‐trial sessions, pigeons learned to discriminate between 2 stimuli, S1 and S2. Choices of S1 were reinforced only in the first half of the session and choices of S2 were reinforced only in the second half. Typically, pigeons choose S2 before the contingency reverses (anticipatory errors) and S1 after (perseverative errors), suggesting that they time the interval from the beginning of the session to the contingency reversal. To test this hypothesis, we exposed pigeons to a midsession reversal task and, depending on the group, either increased or decreased the ITI duration. We then contrasted the pigeons' performance with the predictions of the Learning‐to‐Time (LeT) model: In both conditions, preference was expected to reverse at the same time as in the previous sessions. When the ITI was doubled, pigeons' preference reversal occurred at half the trial number but at the same time as in the previous sessions. When the ITI was halved, pigeons' preference reversal occurred at a later trial but at an earlier time than in the previous sessions. Hence, pigeons' performance was only partially consistent with the predictions of LeT, suggesting that besides timing, other sources of control, such as the outcome of previous trials, seem to influence choice.

中文翻译：

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中期逆转任务中试验间隔的阶跃变化：使用时间学习模型预测鸽子的表现

我们的目标是评估时间在赛中逆转任务中鸽子表现的作用。在离散试验阶段，鸽子学会了区分 2 种刺激，S1 和 S2。S1 的选择只在前半部分得到强化，S2 的选择只在下半部分得到强化。通常，鸽子在意外逆转（预期错误）之前选择 S2，在（持续错误）之后选择 S1，这表明他们将时间间隔从比赛开始到意外逆转。为了验证这一假设，我们让鸽子接受了一项中期逆转任务，并根据组别增加或减少了 ITI 持续时间。然后，我们将鸽子的表现与 Learning-to-Time (LeT) 模型的预测进行了对比：在这两种情况下，与前几届会议一样，这种偏好预计会同时逆转。当 ITI 加倍时，鸽子的偏好逆转发生在试验次数的一半，但与前几届比赛的时间相同。当 ITI 减半时，鸽子的偏好逆转发生在较晚的试验中，但比前几场比赛的时间早。因此，鸽子的表现与 LeT 的预测仅部分一致，这表明除了时间之外，其他控制来源，例如先前试验的结果，似乎会影响选择。偏好逆转发生在较晚的试验中，但比前几次试验的时间早。因此，鸽子的表现与 LeT 的预测仅部分一致，这表明除了时间之外，其他控制来源，例如先前试验的结果，似乎会影响选择。偏好逆转发生在较晚的试验中，但比前几次试验的时间早。因此，鸽子的表现与 LeT 的预测仅部分一致，这表明除了时间之外，其他控制来源，例如先前试验的结果，似乎会影响选择。