In human learning a distinction has been made between implicit and explicit learning. Implicit learning is thought involve automatic processes of the kind involved in Pavlovian conditioning, while explicit learning is thought to involve conscious hypothesis testing and rule formation, in which the ability to report the rule used to learn the task is taken as evidence. Because non-verbal animals cannot provide such evidence, several indirect methods have been proposed. One of these methods is faster learning by humans of certain explicitly learned tasks than implicitly learned tasks, but pigeons do not show a similar difference. Another method involves the 1-back-reinforcement conditional discrimination (if A choose X, if B choose Y) in which feedback following the conditional response is delayed until the next trial. It has been argued that implicit learning cannot occur over the delay between the conditional response and the reinforcer on the next trial, yet, it has been found that monkeys can learn this 1-back reinforcement task. We have argued that such learning can occur implicitly. We have found that pigeons, a species not thought to learn explicitly, can show significant learning of both 1-back reinforcement matching and 1-back reinforcement mismatching, two versions of the 1-back-reinforcement conditional discrimination. We propose that the evidence for explicit learning by non-verbal animals suffers from alternative simpler accounts because the rationale for explicit learning is based on assumptions that likely are not correct.

在人类学习中，内隐学习和外显学习之间存在区别。内隐学习被认为涉及巴甫洛夫条件反射所涉及的那种自动过程，而外显学习被认为涉及有意识的假设检验和规则形成，其中报告用于学习任务的规则的能力被视为证据。由于非语言动物无法提供此类证据，因此提出了几种间接方法。其中一种方法是人类对某些显式学习任务的学习比隐式学习任务更快，但鸽子没有表现出类似的差异。另一种方法涉及 1-back-reinforcement 条件判别（如果 A 选择 X，如果 B 选择 Y），其中条件响应之后的反馈被延迟到下一次试验。有人认为，在下一次试验中，条件反应和强化物之间的延迟不会发生内隐学习，然而，已经发现猴子可以学习这种 1-back 强化任务。我们认为这种学习可以隐含地发生。我们发现，鸽子，一种不被认为是明确学习的物种，可以显示出对 1-back 强化匹配和 1-back 强化不匹配的显着学习，这是 1-back-reinforcement 条件辨别的两个版本。我们建议非语言动物的显式学习的证据受到其他更简单的解释的影响，因为显式学习的基本原理是基于可能不正确的假设。已经发现猴子可以学习这种 1-back 强化任务。我们认为这种学习可以隐含地发生。我们发现，鸽子，一种不被认为是明确学习的物种，可以显示出对 1-back 强化匹配和 1-back 强化不匹配的显着学习，这是 1-back-reinforcement 条件辨别的两个版本。我们建议非语言动物的显式学习的证据受到其他更简单的解释的影响，因为显式学习的基本原理是基于可能不正确的假设。已经发现猴子可以学习这种 1-back 强化任务。我们认为这种学习可以隐含地发生。我们发现，鸽子，一种不被认为是明确学习的物种，可以显示出对 1-back 强化匹配和 1-back 强化不匹配的显着学习，这是 1-back-reinforcement 条件辨别的两个版本。我们建议非语言动物的显式学习的证据受到其他更简单的解释的影响，因为显式学习的基本原理是基于可能不正确的假设。可以显示对 1-back 强化匹配和 1-back 强化不匹配的显着学习，这是 1-back-reinforcement 条件辨别的两个版本。我们建议非语言动物的显式学习的证据受到其他更简单的解释的影响，因为显式学习的基本原理是基于可能不正确的假设。可以显示对 1-back 强化匹配和 1-back 强化不匹配的显着学习，这是 1-back-reinforcement 条件辨别的两个版本。我们建议非语言动物的显式学习的证据受到其他更简单的解释的影响，因为显式学习的基本原理是基于可能不正确的假设。