Should "I" be used in an introduction for a psychology experiment/research proposal? Why or why not?

Using the first-person pronoun "I" in the introduction of a psychology experiment or research proposal depends on the conventions of academic writing and the specific guidelines provided by your institution or the publication you are submitting to.

In many cases, academic writing in the sciences, including psychology, often adheres to a more formal and objective tone. Using "I" may be discouraged to maintain a sense of objectivity and to focus on the research rather than the researcher. Instead, third-person language or passive voice is commonly preferred.

However, some situations or specific guidelines may allow or even encourage the use of first-person pronouns. For instance, if the assignment or journal specifically requests a personal reflection or narrative approach, using "I" could be appropriate.

In summary, it's crucial to follow the guidelines provided by your institution or the specific requirements of the publication you're submitting to. The choice to use "I" or not in the introduction should align with the conventions of academic writing in the given context.