Yes, you are able to revisit live pulses to change your responses. However, once the pulse closes, you will not be able to make any updates.
You can re-access your Dialogue pulse through the original link provided, navigate to the ANSWER tab, and the specific question you want to update.
For a metric question, simply change your selection and the latest response will be automatically saved.
For the open-ended question, you can enter additional responses or delete your previous response by clicking on the trash icon.