This paper investigates how ChatGPT, an AI chatbot developed by OpenAI, can be introduced to STEM education, specifically, an "Introduction to Cognitive Neuroscience" class. Using mixed-method research, the study conducted an experiment to collect students' performance scores and their feedback to examine the potential impacts from ChatGPT on their critical thinking skills, long-term retention of knowledge, and group learning interactions through collaborative projects. The results demonstrate significant disparities between AI-generated (ChatGPT) and human input. Upon analyzing the grade fluctuations before and after receiving input, it was shown that students who received feedback from ChatGPT encountered a more significant decrease (median = -12) compared to those who received feedback from humans (median = -5). This result indicates potential shortcomings in the effectiveness of AI feedback. Human feedback has significantly higher Retention Proxy scores than that of ChatGPT feedback, suggesting that human feedback can be potentially more effective in fostering long-term retention of course material. Investigation into collaboration dynamics of learning found that feedback given by humans tends to be more positive (63 vs. 40 in sentiment score) and also more focused on improvement and understanding. The theme of feedback is different between two conditions. That is, human feedback emphasizes scientific and detailed approaches while ChatGPT feedback emphasizes educational aspects and cognitive functions. These results indicate that while ChatGPT has potential benefits on educational settings, human feedback is superior in many ways. This study contributes to the continuing discourse on the use of AI in STEM education and emphasizes the significance of maintaining a harmonious combination of AI and human involvement in delivering educational feedback.