Once you complete "Reboot," you’ll be able to access to all of Talos 1 again. If and when you make your way back to the Arboretum — say, for objectives like "Gardening Tips," "Golden Gun," "Talos Smuggling Ring" or "Shuttle Advent" — you’ll get a call on your TranScribe from Dr. Igwe. This obviously presumes that you saved Dr. Igwe during "This Side Up."
Dr. Igwe asks you to retrieve a connectome — a specific neuormod, basically — from his cabin. He’ll also give you an audio sample that you’ll need to open his safe.
Dr. Igwe asked me to retrieve a connectome related to the late Gustav Leitner, a famed pianist who had his brain scanned at TranStar. Igwe gave me an audio sample of a concerto snippet that will open a safe in his cabin when played from my TranScribe.
Retrieve Gustav Leitner's connectome from Dr. Igwe's quarters
Dr. Igwe’s cabin is in Crew Cabins A. It’s the second from the end of the hall on the right. Inside, you’ll have an unhelpful marker on your HUD that points to a poster. To get to the safe, you have to navigate your menus and play the concerto sample Dr. Igwe sent you — it’s under Data, Audio Logs, "Leitner Music Sample."
When the recording ends, the poster will slide out of the way revealing the safe. Empty it for a few psi hypos, a suit chipset, a neuromod and the connectome you’re looking for.
Return Gustav Leitner's connectome to Dr. Igwe
Dr. Igwe is hanging out in your office with Mikhaila (assuming you saved her during or after "Reboot") and January. Head back to the Talos 1 Lobby and up to your office. When you talk to him, you’ll close out this optional objective and earn the "Gift to the World" trophy/achievement.